NAME
    SNMP::Info - OO Interface to Network devices and MIBs through SNMP

VERSION
    SNMP::Info - Version 3.972002

AUTHOR
    SNMP::Info is maintained by team of Open Source authors headed by Eric
    Miller, Bill Fenner, Max Baker, Jeroen van Ingen and Oliver Gorwits.

    Please visit <https://github.com/netdisco/snmp-info/> for the most
    up-to-date list of developers.

    SNMP::Info was originally created at UCSC for the Netdisco project
    <http://netdisco.org> by Max Baker.

DEVICES SUPPORTED
    There are now generic classes for most types of device and so the
    authors recommend loading SNMP::Info with AutoSpecify, and then
    reporting to the mail list any missing functionality (such as neighbor
    discovery tables).

SYNOPSIS
     use SNMP::Info;

     my $info = SNMP::Info->new({
                                # Auto Discover your Device Class (Cisco, Juniper, etc ...)
                                AutoSpecify => 1,
                                Debug       => 1,

                                # The rest is passed to SNMP::Session
                                DestHost    => 'router',
                                Community   => 'public',
                                Version     => 2

                                # Parameter reference for SNMPv3
                                # Version   => 3
                                # SecLevel  => 'authPriv', # authPriv|authNoPriv|noAuthNoPriv
                                # SecName   => 'myuser',
                                # AuthProto => 'MD5',      # MD5|SHA
                                # AuthPass  => 'authp4ss',
                                # PrivProto => 'DES',      # DES|AES
                                # PrivPass  => 'pr1vp4ss',
                               });

     my $err = $info->error();
     die $err if defined $err;
     # usually a wrong DestHost or Community or Version if you have trouble here

     my $name  = $info->name();
     my $class = $info->class();
     print "SNMP::Info is using this device class : $class\n";

     # Find out the Duplex status for the ports
     my $interfaces = $info->interfaces();
     my $i_duplex   = $info->i_duplex();

     # Get CDP Neighbor info
     my $c_if       = $info->c_if();
     my $c_ip       = $info->c_ip();
     my $c_port     = $info->c_port();

     # Print out data per port
     foreach my $iid (keys %$interfaces){
        my $duplex = $i_duplex->{$iid};
        # Print out physical port name, not snmp iid
        my $port  = $interfaces->{$iid};

        print "$port: ";
        print "$duplex duplex" if defined $duplex;

        # The CDP Table has table entries different than the interface tables.
        # So we use c_if to get the map from cdp table to interface table.

        my %c_map = reverse %$c_if;
        my $c_key = $c_map{$iid};
        unless (defined $c_key) {
             print "\n\n";
             next;
         }
        my $neighbor_ip   = $c_ip->{$c_key};
        my $neighbor_port = $c_port->{$c_key};

        print " connected to $neighbor_ip / $neighbor_port\n" if defined $neighbor_ip;
        print "\n";

     }

SUPPORT
    Please direct all support, help, and bug requests to the snmp-info-users
    Mailing List at
    <http://lists.sourceforge.net/lists/listinfo/snmp-info-users>.

DESCRIPTION
    SNMP::Info gives an object oriented interface to information obtained
    through SNMP.

    This module is geared towards network devices. Subclasses exist for a
    number of network devices and common MIBs.

    The idea behind this module is to give a common interface to data from
    network devices, leaving the device-specific hacks behind the scenes in
    subclasses.

    In the SYNOPSIS example we fetch the name of all the ports on the device
    and the duplex setting for that port with two methods -- interfaces()
    and i_duplex().

    The information may be coming from any number of MIB files and is very
    vendor specific. SNMP::Info provides you a common method for all
    supported devices.

    Adding support for your own device is easy, and takes little SNMP
    knowledge.

    The module is not limited to network devices. Any MIB or device can be
    given an objected oriented front-end by making a module that consists of
    a couple hashes. See EXTENDING SNMP::INFO.

REQUIREMENTS
    1. Net-SNMP
        To use this module, you must have Net-SNMP installed on your system.
        More specifically you need the Perl modules that come with it.

        DO NOT INSTALL SNMP:: or Net::SNMP from CPAN!

        The SNMP module is matched to an install of net-snmp, and must be
        installed from the net-snmp source tree.

        The Perl module "SNMP" is found inside the net-snmp distribution. Go
        to the perl/ directory of the distribution to install it, or run
        "./configure --with-perl-modules" from the top directory of the
        net-snmp distribution.

        Net-SNMP can be found at http://net-snmp.sourceforge.net

        Version 5.3.2 or greater is recommended.

        Versions 5.0.1, 5.0301 and 5.0203 have issues with bulkwalk and are
        not supported.

        Redhat Users: Some versions that come with certain versions of
        Redhat/Fedora don't have the Perl library installed. Uninstall the
        RPM and install by hand.

    2. MIBS
        SNMP::Info operates on textual descriptors found in MIBs.

        If you are using SNMP::Info separate from Netdisco, download the
        Netdisco MIB package at
        <https://github.com/netdisco/netdisco-mibs/releases/latest/>

        Make sure that your snmp.conf is updated to point to your MIB
        directory and that the MIBs are world-readable.

DESIGN GOALS
    1. Use of textual MIB leaf identifier and enumerated values

        *   All values are retrieved via MIB Leaf node names

            For example SNMP::Info has an entry in its %GLOBALS hash for
            ``sysName'' instead of 1.3.6.1.2.1.1.5.

        *   Data returned is in the enumerated value form.

            For Example instead of looking up 1.3.6.1.2.1.2.2.1.3 and
            getting back 23

            SNMP::Info will ask for "RFC1213-MIB::ifType" and will get back
            "ppp".

    2. SNMP::Info is easily extended to new devices
        You can create a new subclass for a device by providing four hashes
        : %GLOBALS, %MIBS, %FUNCS, and %MUNGE.

        Or you can override any existing methods from a parent class by
        making a short subroutine.

        See the section EXTENDING SNMP::INFO for more details.

        When you make a new subclass for a device, please be sure to send it
        back to the developers (via a github pull request or the mailing
        list) for inclusion in the next version.

SUBCLASSES
    These are the subclasses that implement MIBs and support devices:

    Required MIBs not included in the install instructions above are noted
    here.

  MIB Subclasses
    These subclasses implement method to access one or more MIBs. These are
    not used directly, but rather inherited from device subclasses.

    For more info run "perldoc" on any of the following module names.

    SNMP::Info::AdslLine
        SNMP Interface to the ADSL-LINE-MIB for ADSL interfaces.

        Requires the ADSL-LINE-MIB, down loadable from Cisco.

        See documentation in SNMP::Info::AdslLine for details.

    SNMP::Info::Aggregate
        SNMP Interface to IF-MIB "ifStackTable" Aggregated Links

        See documentation in SNMP::Info::Aggregate for details.

    SNMP::Info::Airespace
        AIRESPACE-WIRELESS-MIB and AIRESPACE-SWITCHING-MIB. Inherited by
        devices based on the Airespace wireless platform.

        See documentation in SNMP::Info::Airespace for details.

    SNMP::Info::AMAP
        ALCATEL-IND1-INTERSWITCH-PROTOCOL-MIB. Alcatel Mapping Adjacency
        Protocol (AMAP) Support.

        See documentation in SNMP::Info::AMAP for details.

    SNMP::Info::Bridge
        BRIDGE-MIB (RFC1286). Q-BRIDGE-MIB. Inherited by devices with Layer2
        support.

        See documentation in SNMP::Info::Bridge for details.

    SNMP::Info::CDP
        CISCO-CDP-MIB. Cisco Discovery Protocol (CDP) Support. Inherited by
        Cisco, Enterasys, and HP devices.

        See documentation in SNMP::Info::CDP for details.

    SNMP::Info::CiscoAgg
        SNMP Interface to Cisco Aggregated Links

        See documentation in SNMP::Info::CiscoAgg for details.

    SNMP::Info::CiscoBGP
        CISCO-BGP4-MIB. Cisco BGPv4 support. Inherited by Cisco devices with
        Layer3 support.

        See documentation in SNMP::Info::CiscoBGP for details.

    SNMP::Info::CiscoConfig
        CISCO-CONFIG-COPY-MIB, CISCO-FLASH-MIB, and OLD-CISCO-SYS-MIB. These
        OIDs facilitate the writing of configuration files.

        See documentation in SNMP::Info::CiscoConfig for details.

    SNMP::Info::CiscoPortSecurity
        CISCO-PORT-SECURITY-MIB and CISCO-PAE-MIB.

        See documentation in SNMP::Info::CiscoPortSecurity for details.

    SNMP::Info::CiscoPower
        CISCO-POWER-ETHERNET-EXT-MIB.

        See documentation in SNMP::Info::CiscoPower for details.

    SNMP::Info::CiscoQOS
        CISCO-CLASS-BASED-QOS-MIB. A collection of OIDs providing
        information about a Cisco device's QOS config.

        See documentation in SNMP::Info::CiscoQOS for details.

    SNMP::Info::CiscoRTT
        CISCO-RTTMON-MIB. A collection of OIDs providing information about a
        Cisco device's RTT values.

        See documentation in SNMP::Info::CiscoRTT for details.

    SNMP::Info::CiscoStack
        CISCO-STACK-MIB.

        See documentation in SNMP::Info::CiscoStack for details.

    SNMP::Info::CiscoStats
        OLD-CISCO-CPU-MIB, CISCO-PROCESS-MIB, and CISCO-MEMORY-POOL-MIB.
        Provides common interfaces for memory, cpu, and os statistics for
        Cisco devices.

        See documentation in SNMP::Info::CiscoStats for details.

    SNMP::Info::CiscoStpExtensions
        CISCO-STP-EXTENSIONS-MIB

        See documentation in SNMP::Info::CiscoStpExtensions for details.

    SNMP::Info::CiscoVTP
        CISCO-VTP-MIB, CISCO-VLAN-MEMBERSHIP-MIB,
        CISCO-VLAN-IFTABLE-RELATIONSHIP-MIB

        See documentation in SNMP::Info::CiscoVTP for details.

    SNMP::Info::DocsisCM
        SNMP Interface for DOCSIS Cable Modems

        See documentation in SNMP::Info::DocsisCM for details.

    SNMP::Info::DocsisHE
        SNMP Interface for DOCSIS CMTS

        See documentation in SNMP::Info::DocsisHE for details.

    SNMP::Info::EDP
        Extreme Discovery Protocol. EXTREME-EDP-MIB

        See documentation in SNMP::Info::EDP for details.

    SNMP::Info::Entity
        ENTITY-MIB. Used for device info in Cisco and other vendors.

        See documentation in SNMP::Info::Entity for details.

    SNMP::Info::EtherLike
        EtherLike-MIB (RFC1398) - Some Layer3 devices implement this MIB, as
        well as some Aironet Layer 2 devices (non Cisco).

        See documentation in SNMP::Info::EtherLike for details.

    SNMP::Info::FDP
        Foundry (Brocade) Discovery Protocol. FOUNDRY-SN-SWITCH-GROUP-MIB

        See documentation in SNMP::Info::FDP for details.

    SNMP::Info::IEEE802_Bridge
        SNMP Interface to data available through the IEEE8021-Q-BRIDGE-MIB

        See documentation in SNMP::Info::IEEE802_Bridge for details.

    SNMP::Info::IEEE802dot11
        IEEE802dot11-MIB. A collection of OIDs providing information about
        standards based 802.11 wireless devices.

        See documentation in SNMP::Info::IEEE802dot11 for details.

    SNMP::Info::IEEE802dot3ad
        SNMP Interface to IEEE Aggregated Links. IEEE8023-LAG-MIB

        See documentation in SNMP::Info::IEEE802dot3ad for details.

    SNMP::Info::IPv6
        SNMP Interface for obtaining configured IPv6 addresses and mapping
        IPv6 addresses to MAC addresses and interfaces, using information
        from IP-MIB, IPV6-MIB and/or CISCO-IETF-IP-MIB.

        See documentation in SNMP::Info::IPv6 for details.

    SNMP::Info::LLDP
        LLDP-MIB, LLDP-EXT-DOT1-MIB, and LLDP-EXT-DOT3-MIB. Link Layer
        Discovery Protocol (LLDP) Support.

        See documentation in SNMP::Info::LLDP for details.

    SNMP::Info::MAU
        MAU-MIB (RFC2668). Some Layer2 devices use this for extended
        Ethernet (Medium Attachment Unit) interface information.

        See documentation in SNMP::Info::MAU for details.

    SNMP::Info::MRO
        Method resolution introspection for SNMP::Info

        See documentation in SNMP::Info::MRO for details.

    SNMP::Info::NortelStack
        S5-AGENT-MIB, S5-CHASSIS-MIB.

        See documentation in SNMP::Info::NortelStack for details.

    SNMP::Info::PortAccessEntity
        IEEE8021-PAE-MIB

        See documentation in SNMP::Info::PortAccessEntity for details.

    SNMP::Info::PowerEthernet
        POWER-ETHERNET-MIB

        See documentation in SNMP::Info::PowerEthernet for details.

    SNMP::Info::RapidCity
        RAPID-CITY. Inherited by Avaya switches for duplex and VLAN
        information.

        See documentation in SNMP::Info::RapidCity for details.

    SNMP::Info::SONMP
        SynOptics Network Management Protocol (SONMP) SYNOPTICS-ROOT-MIB,
        S5-ETH-MULTISEG-TOPOLOGY-MIB. Inherited by
        Avaya/Nortel/Bay/Synoptics switches and hubs.

        See documentation in SNMP::Info::SONMP for details.

  Device Subclasses
    These subclasses inherit from one or more classes to provide a common
    interface to data obtainable from network devices.

    All the required MIB files are included in the netdisco-mib package.
    (See Above).

    SNMP::Info::Layer1
        Generic Layer1 Device subclass.

        See documentation in SNMP::Info::Layer1 for details.

        SNMP::Info::Layer1::Allied
            Subclass for Allied Telesis Repeaters / Hubs.

            Requires ATI-MIB

            See documentation in SNMP::Info::Layer1::Allied for details.

        SNMP::Info::Layer1::Asante
            Subclass for Asante 1012 Hubs.

            Requires ASANTE-HUB1012-MIB

            See documentation in SNMP::Info::Layer1::Asante for details.

        SNMP::Info::Layer1::Bayhub
            Subclass for Nortel/Bay hubs. This includes System 5000, 100
            series, 200 series, and probably more.

            See documentation in SNMP::Info::Layer1::Bayhub for details.

        SNMP::Info::Layer1::Cyclades
            Subclass for Cyclades/Avocent terminal servers.

            See documentation in SNMP::Info::Layer1::Cyclades for details.

        SNMP::Info::Layer1::S3000
            Subclass for Bay/Synoptics hubs. This includes System 3000,
            281X, and probably more.

            See documentation in SNMP::Info::Layer1::S3000 for details.

    SNMP::Info::Layer2
        Generic Layer2 Device subclass.

        See documentation in SNMP::Info::Layer2 for details.

        SNMP::Info::Layer2::3Com
            Subclass for L2 3Com Switches.

            See documentation in SNMP::Info::Layer2::3Com for details.

        SNMP::Info::Layer2::Adtran
            Subclass for Adtran devices.

            See documentation in SNMP::Info::Layer2::Adtran for details.

        SNMP::Info::Layer2::Aerohive
            Subclass for Aerohive / Extreme access points.

            See documentation in SNMP::Info::Layer2::Aerohive for details.

        SNMP::Info::Layer2::Airespace
            Subclass for Cisco (Airespace) wireless controllers.

            See documentation in SNMP::Info::Layer2::Airespace for details.

        SNMP::Info::Layer2::Aironet
            Class for Cisco Aironet wireless devices that run IOS. See also
            SNMP::Info::Layer3::Aironet for Aironet devices that don't run
            IOS.

            See documentation in SNMP::Info::Layer2::Aironet for details.

        SNMP::Info::Layer2::Allied
            Allied Telesis switches.

            See documentation in SNMP::Info::Layer2::Allied for details.

        SNMP::Info::Layer2::Atmedia
            Subclass for atmedia encryptors.

            See documentation in SNMP::Info::Layer2::Atmedia for details.

        SNMP::Info::Layer2::Baystack
            Subclass for Avaya/Nortel/Bay Ethernet Switch/Baystack switches.
            This includes 303, 304, 350, 380, 410, 420, 425, 450, 460, 470
            series, 2500 series, 4000 series, 5000 series, Business Ethernet
            Switch (BES), Business Policy Switch (BPS), VSP 7000 series, and
            probably others.

            See documentation in SNMP::Info::Layer2::Baystack for details.

        SNMP::Info::Layer2::C1900
            Subclass for Cisco Catalyst 1900 and 1900c Devices running
            CatOS.

            See documentation in SNMP::Info::Layer2::C1900 for details.

        SNMP::Info::Layer2::C2900
            Subclass for Cisco Catalyst 2900, 2950, 3500XL, and 3548 devices
            running IOS.

            See documentation in SNMP::Info::Layer2::C2900 for details.

        SNMP::Info::Layer2::Catalyst
            Subclass for Cisco Catalyst switches running CatOS. These
            switches usually report a model number that starts with "wsc".
            Note that this class does not support everything that has the
            name Catalyst.

            See documentation in SNMP::Info::Layer2::Catalyst for details.

        SNMP::Info::Layer2::Centillion
            Subclass for Nortel/Bay Centillion and 5000BH ATM switches.

            See documentation in SNMP::Info::Layer2::Centillion for details.

        SNMP::Info::Layer2::Cisco
            Generic Cisco subclass for layer 2 devices that are not yet
            supported in more specific subclasses and the base layer 2 Cisco
            class for other device specific layer 2 Cisco classes.

            See documentation in SNMP::Info::Layer2::Cisco for details.

        SNMP::Info::Layer2::CiscoSB
            Subclass for Cisco's "Small Business" product line, acquired
            from Linksys. This currently comprises the Sx300/500 line of
            switches.

            See documentation in SNMP::Info::Layer2::CiscoSB for details.

        SNMP::Info::Layer2::Exinda
            Subclass for Exinda / GFI Network Orchestrator traffic shapers.

            See documentation in SNMP::Info::Layer2::Exinda for details.

        SNMP::Info::Layer2::Hirschmann
            Subclass for Hirschmann switches

            See documentation in SNMP::Info::Layer2::Hirschmann for details.

        SNMP::Info::Layer2::HP
            Subclass for more recent HP Procurve Switches.

            Requires HP-ICF-OID and ENTITY-MIB downloaded from HP.

            See documentation in SNMP::Info::Layer2::HP for details.

        SNMP::Info::Layer2::HP4000
            Subclass for older HP Procurve Switches

            Requires HP-ICF-OID and ENTITY-MIB downloaded from HP.

            See documentation in SNMP::Info::Layer2::HP4000 for details.

        SNMP::Info::Layer2::HPVC
            Subclass for HP Virtual Connect Switches

            See documentation in SNMP::Info::Layer2::HPVC for details.

        SNMP::Info::Layer2::Kentrox
            Class for Kentrox DataSMART DSU/CSU.

            See documentation in SNMP::Info::Layer2::Kentrox for details.

        SNMP::Info::Layer2::N2270
            Subclass for Nortel 2270 wireless switches.

            See documentation in SNMP::Info::Layer2::N2270 for details.

        SNMP::Info::Layer2::NAP222x
            Subclass for Nortel 222x series wireless access points.

            See documentation in SNMP::Info::Layer2::NAP222x for details.

        SNMP::Info::Layer2::Netgear
            Subclass for Netgear switches

            See documentation in SNMP::Info::Layer2::Netgear for details.

        SNMP::Info::Layer2::Nexans
            Subclass for Nexans switches

            See documentation in SNMP::Info::Layer2::Nexans for details.

        SNMP::Info::Layer2::NWSS2300
            SNMP Interface to Avaya (Trapeze) Wireless Controllers

            See documentation in SNMP::Info::Layer2::NWSS2300 for details.

        SNMP::Info::Layer2::Orinoco
            Subclass for Orinoco/Proxim wireless access points.

            See documentation in SNMP::Info::Layer2::Orinoco for details.

        SNMP::Info::Layer2::Trapeze
            SNMP Interface to Juniper (Trapeze) Wireless Controllers

            See documentation in SNMP::Info::Layer2::Trapeze for details.

        SNMP::Info::Layer2::Sixnet
            SNMP Interface to Sixnet industrial switches

            See documentation in SNMP::Info::Layer2::Sixnet for details.

        SNMP::Info::Layer2::Ubiquiti
            SNMP Interface to Ubiquiti Access Points and other devices

            See documentation in SNMP::Info::Layer2::Ubiquiti for details.

        SNMP::Info::Layer2::ZyXEL_DSLAM
            Zyxel DSLAMs. Need I say more?

            See documentation in SNMP::Info::Layer2::ZyXEL_DSLAM for
            details.

    SNMP::Info::Layer3
        Generic Layer3 and Layer2+3 Device subclass.

        See documentation in SNMP::Info::Layer3 for details.

        SNMP::Info::Layer3::Aironet
            Subclass for Cisco Aironet wireless access points (AP) not
            running IOS. These are usually older devices.

            Note SNMP::Info::Layer2::Aironet

            See documentation in SNMP::Info::Layer3::Aironet for details.

        SNMP::Info::Layer3::AlcatelLucent
            Alcatel-Lucent OmniSwitch Class.

            See documentation in SNMP::Info::Layer3::AlcatelLucent for
            details.

        SNMP::Info::Layer3::AlteonAD
            Subclass for Radware Alteon Series ADC switches and Nortel
            BladeCenter Layer2-3 GbE Switch Modules.

            See documentation in SNMP::Info::Layer3::AlteonAD for details.

        SNMP::Info::Layer3::Altiga
            See documentation in SNMP::Info::Layer3::Altiga for details.

        SNMP::Info::Layer3::Meraki
            See documentation in SNMP::Info::Layer3::Meraki for details.

        SNMP::Info::Layer3::Arista
            See documentation in SNMP::Info::Layer3::Arista for details.

        SNMP::Info::Layer3::Aruba
            Subclass for Aruba wireless switches.

            See documentation in SNMP::Info::Layer3::Aruba for details.

        SNMP::Info::Layer3::ArubaCX
            SNMP Interface to L3 Devices running ArubaOS-CX

            See documentation in SNMP::Info::Layer3::ArubaCX for details.

        SNMP::Info::Layer3::BayRS
            Subclass for Avaya/Nortel/Bay Multiprotocol/BayRS routers. This
            includes BCN, BLN, ASN, ARN, AN, 2430, and 5430 routers.

            See documentation in SNMP::Info::Layer3::BayRS for details.

        SNMP::Info::Layer3::BlueCoatSG
            Subclass for BlueCoat SG series proxy devices.

            See documentation in SNMP::Info::Layer3::BlueCoatSG for details.

        SNMP::Info::Layer3::C1300
            See documentation in SNMP::Info::Layer3::C1300 for details.

        SNMP::Info::Layer3::C3550
            Subclass for Cisco Catalyst 3550,3540,3560 2/3 switches running
            IOS.

            See documentation in SNMP::Info::Layer3::C3550 for details.

        SNMP::Info::Layer3::C4000
            This class covers Catalyst 4000s and 4500s.

            See documentation in SNMP::Info::Layer3::C4000 for details.

        SNMP::Info::Layer3::C6500
            This class covers Catalyst 6500 series running CatOS or IOS, as
            well as Catalyst 2960, 2970, 3750 and 3850 series, including
            blade switches CBS30x0 and CBS31x0 series, all running IOS.

            See documentation in SNMP::Info::Layer3::C6500 for details.

        SNMP::Info::Layer3::CheckPoint
            Subclass for CheckPoint devices.

            See documentation in SNMP::Info::Layer3::CheckPoint for details.

        SNMP::Info::Layer3::Ciena
            Subclass for Ciena devices.

            See documentation in SNMP::Info::Layer3::Ciena for details.

        SNMP::Info::Layer3::Cisco
            This is a simple wrapper around layer 3 for IOS devices and the
            base layer 3 Cisco class for other device specific layer 3 Cisco
            classes.

            See documentation in SNMP::Info::Layer3::Cisco for details.

        SNMP::Info::Layer3::CiscoASA
            Subclass for Cisco Adaptive Security Appliances.

            See documentation in SNMP::Info::Layer3::CiscoASA for details.

        SNMP::Info::Layer3::CiscoFWSM
            Subclass for Cisco Firewall Services Modules.

            See documentation in SNMP::Info::Layer3::CiscoFWSM for details.

        SNMP::Info::Layer3::CiscoSwitch
            Base class for L3 Cisco switches. See documentation in
            SNMP::Info::Layer3::CiscoSwitch for details.

        SNMP::Info::Layer3::Contivity
            Subclass for Avaya/Nortel Contivity/VPN Routers.

            See documentation in SNMP::Info::Layer3::Contivity for details.

        SNMP::Info::Layer3::Cumulus
            Subclass for Cumulus Networks Routers.

            See documentation in SNMP::Info::Layer3::Cumulus for details.

        SNMP::Info::Layer3::Dell
            Subclass for Dell PowerConnect switches. The IBM BladeCenter
            Gigabit Ethernet Switch Module and some Linksys switches also
            use this module based upon MIB support.

            See documentation in SNMP::Info::Layer3::Dell for details.

        SNMP::Info::Layer3::DLink
            Subclass for DLink devices.

            See documentation in SNMP::Info::Layer3::DLink for details.

        SNMP::Info::Layer3::Enterasys
            Subclass for Enterasys devices.

            See documentation in SNMP::Info::Layer3::Enterasys for details.

        SNMP::Info::Layer3::ERX
            Subclass for Juniper ERX switches.

            See documentation in SNMP::Info::Layer3::ERX for details.

        SNMP::Info::Layer3::Extreme
            Subclass for Extreme Networks switches.

            See documentation in SNMP::Info::Layer3::Extreme for details.

        SNMP::Info::Layer3::ExtremeWing
            Subclass for Extreme WiNG APs.

            See documentation in SNMP::Info::Layer3::ExtremeWing for
            details.

        SNMP::Info::Layer3::F5
            Subclass for F5 devices.

            See documentation in SNMP::Info::Layer3::F5 for details.

        SNMP::Info::Layer3::Force10
            Subclass for Force10 devices.

            See documentation in SNMP::Info::Layer3::Force10 for details.

        SNMP::Info::Layer3::Fortinet
            Subclass for Fortinet devices.

            See documentation in SNMP::Info::Layer3::Fortinet for details.

        SNMP::Info::Layer3::Foundry
            Subclass for Brocade (Foundry) Network devices.

            See documentation in SNMP::Info::Layer3::Foundry for details.

        SNMP::Info::Layer3::Genua
            Subclass for Genua security devices.

            See documentation in SNMP::Info::Layer3::Genua for details.

        SNMP::Info::Layer3::H3C
            SNMP Interface to Layer 3 Devices, H3C & HP A-series.

            See documentation in SNMP::Info::Layer3::H3C for details.

        SNMP::Info::Layer3::HP9300
            Subclass for HP network devices which Foundry Networks was the
            Original Equipment Manufacturer (OEM) such as the HP ProCurve
            9300 and 6300 series.

            See documentation in SNMP::Info::Layer3::HP9300 for details.

        SNMP::Info::Layer3::Huawei
            SNMP Interface to Huawei Layer 3 switches and routers.

            See documentation in SNMP::Info::Layer3::Huawei for details.

        SNMP::Info::Layer3::IBMGbTor
            SNMP Interface to IBM Rackswitch (formerly Blade Network
            Technologies) network devices. Lenovo acquired these from IBM
            and is now selling them under the Lenovo brand.

            See documentation in SNMP::Info::Layer3::IBMGbTor for details.

        SNMP::Info::Layer3::Juniper
            Subclass for Juniper devices.

            See documentation in SNMP::Info::Layer3::Juniper for details.

        SNMP::Info::Layer3::Lantronix
            Subclass for Lantronix devices.

            See documentation in SNMP::Info::Layer3::Lantronix for details.

        SNMP::Info::Layer3::Lenovo
            Subclass for Lenovo switches running CNOS.

            See documentation in SNMP::Info::Layer3::Lenovo for details.

        SNMP::Info::Layer3::Microsoft
            Subclass for Generic Microsoft Routers running Microsoft Windows
            OS.

            See documentation in SNMP::Info::Layer3::Microsoft for details.

        SNMP::Info::Layer3::Mikrotik
            Subclass for Mikrotik devices running RouterOS.

            See documentation in SNMP::Info::Layer3::Mikrotik for details.

        SNMP::Info::Layer3::N1600
            Subclass for Avaya/Nortel Ethernet Routing Switch 1600 series.

            See documentation in SNMP::Info::Layer3::N1600 for details.

        SNMP::Info::Layer3::Netonix
            Subclass for Netonix switches.

            See documentation in SNMP::Info::Layer3::Netonix for details.

        SNMP::Info::Layer3::NetSNMP
            Subclass for host systems running Net-SNMP.

            See documentation in SNMP::Info::Layer3::NetSNMP for details.

        SNMP::Info::Layer3::Netscreen
            Subclass for Juniper NetScreen.

            See documentation in SNMP::Info::Layer3::Netscreen for details.

        SNMP::Info::Layer3::Nexus
            Subclass for Cisco Nexus devices running NX-OS.

            See documentation in SNMP::Info::Layer3::Nexus for details.

        SNMP::Info::Layer3::OneAccess
            Subclass for OneAccess routers.

            See documentation in SNMP::Info::Layer3::OneAccess for details.

        SNMP::Info::Layer3::PacketFront
            Subclass for PacketFront DRG series CPE.

            See documentation in SNMP::Info::Layer3::PacketFront for
            details.

        SNMP::Info::Layer3::PaloAlto
            Subclass for Palo Alto firewalls.

            See documentation in SNMP::Info::Layer3::PaloAlto for details.

        SNMP::Info::Layer3::Passport
            Subclass for Avaya/Nortel Ethernet Routing Switch/Passport 8000
            series, Accelar, and VSP 9000 series switches.

            See documentation in SNMP::Info::Layer3::Passport for details.

        SNMP::Info::Layer3::Pf
            Subclass for FreeBSD-Based Firewalls using Pf /Pf Sense

            See documentation in SNMP::Info::Layer3::Pf for details.

        SNMP::Info::Layer3::Pica8
            Subclass for Pica8 devices.

            See documentation in SNMP::Info::Layer3::Pica8 for details.

        SNMP::Info::Layer3::Redlion
            Subclass for redlion routers.

            See documentation in SNMP::Info::Layer3::Redlion for details.

        SNMP::Info::Layer3::SilverPeak
            Subclass for SilverPeak devices.

            See documentation in SNMP::Info::Layer3::SilverPeak for details.

        SNMP::Info::Layer3::Scalance
            Subclass for Siemens Scalance devices.

            See documentation in SNMP::Info::Layer3::Scalance for details.

        SNMP::Info::Layer3::SonicWALL
            Subclass for generic SonicWALL devices.

            See documentation in SNMP::Info::Layer3::SonicWALL for details.

        SNMP::Info::Layer3::Steelfusion
            Subclass for Riverbed Steelfusion WAN optimization appliances.

            See documentation in SNMP::Info::Layer3::Steelfusion for
            details.

        SNMP::Info::Layer3::Steelhead
            Subclass for Riverbed Steelhead WAN optimization appliances.

            See documentation in SNMP::Info::Layer3::Steelhead for details.

        SNMP::Info::Layer3::SteelheadEx
            Subclass for Riverbed SteelheadEx WAN optimization appliances.

            See documentation in SNMP::Info::Layer3::SteelheadEx for
            details.

        SNMP::Info::Layer3::Sun
            Subclass for Generic Sun Routers running SunOS.

            See documentation in SNMP::Info::Layer3::Sun for details.

        SNMP::Info::Layer3::Tasman
            Subclass for Avaya Secure Routers.

            See documentation in SNMP::Info::Layer3::Tasman for details.

        SNMP::Info::Layer3::Teltonika
            Subclass for Teltonika RUT9xx series routers.

            See documentation in SNMP::Info::Layer3::Teltonika for details.

        SNMP::Info::Layer3::Timetra
            Alcatel-Lucent SR Class.

            See documentation in SNMP::Info::Layer3::Timetra for details.

        SNMP::Info::Layer3::VyOS
            Subclass for VyOS routers.

            See documentation in SNMP::Info::Layer3::VyOS for details.

        SNMP::Info::Layer3::VMware
            Subclass for VMware ESXi hosts.

            See documentation in SNMP::Info::Layer3::VMware for details.

        SNMP::Info::Layer3::Whiterabbit
            Subclass for whiterabbit devices.

            See documentation in SNMP::Info::Layer3::Whiterabbit for
            details.

    SNMP::Info::Layer7
        Generic Layer7 Devices.

        See documentation in SNMP::Info::Layer7 for details.

        SNMP::Info::Layer7::APC
            Subclass for APC UPS devices.

            See documentation in SNMP::Info::Layer7::APC for details.

        SNMP::Info::Layer7::Arbor
            Subclass for Arbor appliances.

            See documentation in SNMP::Info::Layer7::Arbor for details.

        SNMP::Info::Layer7::CiscoIPS
            Subclass for Cisco IPS devices.

            See documentation in SNMP::Info::Layer7::CiscoIPS for details.

        SNMP::Info::Layer7::Gigamon
            Subclass for Gigamon devices.

            See documentation in SNMP::Info::Layer7::Gigamon for details.

        SNMP::Info::Layer7::HWGroup
            Subclass for HW Group devices.

            See documentation in SNMP::Info::Layer7::HWGroup for details.

        SNMP::Info::Layer7::Liebert
            Subclass for Liebert devices.

            See documentation in SNMP::Info::Layer7::Liebert for details.

        SNMP::Info::Layer7::Neoteris
            Subclass for Pulse Secure / Juniper SSL VPN appliances.

            See documentation in SNMP::Info::Layer7::Neoteris for details.

        SNMP::Info::Layer7::Netscaler
            Subclass for Citrix Netscaler appliances.

            See documentation in SNMP::Info::Layer7::Netscaler for details.

Thanks
    Thanks for testing and coding help (in no particular order) to :
    Alexander Barthel, Andy Ford, Alexander Hartmaier, Andrew Herrick, Alex
    Kramarov, Bernhard Augenstein, Bradley Baetz, Brian Chow, Brian Wilson,
    Carlos Vicente, Dana Watanabe, David Pinkoski, David Sieborger, Douglas
    McKeown, Greg King, Ivan Auger, Jean-Philippe Luiggi, Jeroen van Ingen,
    Justin Hunter, Kent Hamilton, Matthew Tuttle, Michael Robbert, Mike
    Hunter, Nicolai Petri, Ralf Gross, Robert Kerr, Nick Nauwelaerts and
    people listed on the Netdisco README!

USAGE
  Constructor
    new()
        Creates a new object and connects via SNMP::Session.

        Always returns an SNMP::Info instance, and you should always check
        for error() as in SYNOPSIS above to be sure of success.

        Will take a bare list of key/value options but we recommend a HASH
        ref as in the example below and SYNOPSIS, to catch syntax errors.

         my $info = SNMP::Info->({ 'Debug'             => 1,
                                   'AutoSpecify'       => 1,
                                   'BigInt'            => 1,
                                   'BulkWalk'          => 1,
                                   'BulkRepeaters'     => 20,
                                   'LoopDetect'        => 1,
                                   'IgnoreNetSNMPConf' => 1,
                                   'DestHost'          => 'myrouter',
                                   'Community'         => 'public',
                                   'Version'           => 2,
                                   'MibDirs'           => ['dir1','dir2','dir3'],
                                });

        SNMP::Info Specific Arguments :

        AutoSpecify
            Returns an object of a more specific device class

            (default 0, which means "off")

        BigInt
            Return Math::BigInt objects for 64 bit counters. Sets on a
            global scope, not object.

            (default 0, which means "off")

        BulkWalk
            Set to 0 to turn off BULKWALK commands for SNMPv2 connections.

            Note that BULKWALK is turned off for Net-SNMP versions 5.1.x
            because of a bug.

            (default 1, which means "on")

        BulkRepeaters
            Set number of MaxRepeaters for BULKWALK operation. See "perldoc
            SNMP" -> bulkwalk() for more info.

            (default 20)

        LoopDetect
            Detects looping during getnext table column walks by comparing
            IIDs for each instance. A loop is detected if the same IID is
            seen more than once and the walk is aborted. Note: This will not
            detect loops during a bulkwalk operation, Net-SNMP's internal
            bulkwalk function must detect the loop.

            Set to 0 to turn off loop detection.

            (default 1, which means "on")

        IgnoreNetSNMPConf
            Net-SNMP version 5.0 and higher read configuration files,
            snmp.conf or snmp.local.conf, from /etc/snmp, /usr/share/snmp,
            /usr/lib(64)/snmp, or $HOME/.snmp and uses those settings to
            automatically parse MIB files, etc.

            Set to 1 "on" to ignore Net-SNMP configuration files by
            overriding the "SNMPCONFPATH" environmental variable during
            object initialization. Note: MibDirs must be defined or Net-SNMP
            will not be able to load MIBs and initialize the object.

            (default 0, which means "off")

        Debug
            Prints Lots of debugging messages. Pass 2 to print even more
            debugging messages.

            (default 0, which means "off")

        DebugSNMP
            Set $SNMP::debugging level for Net-SNMP.

            See SNMP for more details.

        MibDirs
            Array ref to list of directories in which to look for MIBs. Note
            this will be in addition to the ones setup in snmp.conf at the
            system level.

            (default use net-snmp settings only)

        RetryNoSuch
            When using SNMP Version 1, try reading values even if they come
            back as "no such variable in this MIB". Set to false if so
            desired. This feature lets you read SNMPv2 data from an SNMP
            version 1 connection, and should probably be left on.

            (default 1, which means "on")

        Session
            SNMP::Session object to use instead of connecting on own.

            (default creates session automatically)

        Offline
            Causes SNMP::Info to avoid network activity and return data only
            from its cache. If you ask for something not in the cache, an
            error is thrown. See also the cache() and offline() methods.

            (default 0, which means "online")

        Cache
            Pass in a HashRef to prime the cache of retrieved data. Useful
            for creating an instance in "Offline" mode from a previously
            dumped cache. See also the cache() method to retrieve a cache
            after running actual queries.

        OTHER
            All other arguments are passed to SNMP::Session.

            See SNMP::Session for a list of other possible arguments.

        A Note about the wrong Community string or wrong SNMP Version:

        If a connection is using the wrong community string or the wrong
        SNMP version, the creation of the object will not fail. The device
        still answers the call on the SNMP port, but will not return
        information. Check the error() method after you create the device
        object to see if there was a problem in connecting.

        A note about SNMP Versions :

        Some older devices don't support SNMP version 2, and will not return
        anything when a connection under Version 2 is attempted.

        Some newer devices will support Version 1, but will not return all
        the data they might have if you had connected under Version 1.

        When trying to get info from a new device, you may have to try
        version 2 and then fallback to version 1.

    update()
        Replace the existing session with a new one with updated values,
        without re-identifying the device. The only supported changes are to
        Community or Context.

        Clears the object cache.

        This is useful, e.g., when a device supports multiple contexts (via
        changes to the Community string, or via the SNMPv3 Context
        parameter), but a context that you want to access does not support
        the objects (e.g., "sysObjectID", "sysDescr") that we use to
        identify the device.

  Data is Cached
    Methods and subroutines requesting data from a device will only load the
    data once, and then return cached versions of that data.

    Run $info->load_METHOD() where method is something like 'i_name' to
    reload data from a method.

    Run $info->clear_cache() to clear the cache to allow reload of both
    globals and table methods.

    The cache can be retrieved or set using the $info->cache() method. This
    works together with the "Offline" option.

  Object Scalar Methods
    These are for package related data, not directly supplied from SNMP.

    $info->clear_cache()
        Clears the cached data. This includes GLOBALS data and TABLE METHOD
        data.

    $info->debug(1)
        Returns current debug status, and optionally toggles debugging info
        for this object.

    $info->offline([1|0])
        Returns if offline mode is currently turned on for this object.

        Optionally sets the Offline parameter.

    $info->cache([new_cache])
        Returns a HashRef of all cached data in this object. There will be a
        "store" key for table data and then one key for each leaf.

        Optionally sets the cache parameters if passed a HashRef.

    $info->bulkwalk([1|0])
        Returns if bulkwalk is currently turned on for this object.

        Optionally sets the bulkwalk parameter.

    $info->loopdetect([1|0])
        Returns if loopdetect is currently turned on for this object.

        Optionally sets the loopdetect parameter.

    $info->device_type()
        Returns the Subclass name for this device. "SNMP::Info" is returned
        if no more specific class is available.

        First the device is checked for Layer 3 support and a specific
        subclass, then Layer 2 support and subclasses are checked.

        This means that Layer 2 / 3 switches and routers will fall under the
        SNMP::Info::Layer3 subclasses.

        If the device still can be connected to via SNMP::Info, then
        SNMP::Info is returned.

    $info->error(no_clear)
        Returns Error message if there is an error, or undef if there is
        not.

        Reading the error will clear the error unless you set the no_clear
        flag.

    $info->has_layer(3)
        Returns non-zero if the device has the supplied layer in the OSI
        Model

        Returns if the device doesn't support the layers() call.

    $info->snmp_comm()
        Returns SNMP Community string used in connection.

    $info->snmp_ver()
        Returns SNMP Version used for this connection

    $info->specify()
        Returns an object of a more-specific subclass.

         my $info = new SNMP::Info(...);
         # Returns more specific object type
         my $specific = $info->specify();

        Usually this method is called internally from new(AutoSpecify => 1)

        See device_type() entry for how a subclass is chosen.

    $info->cisco_comm_indexing()
        Returns 0. Is an overridable method used for vlan indexing for snmp
        calls on certain Cisco devices.

        See
        <ftp://ftp.cisco.com/pub/mibs/supportlists/wsc5000/wsc5000-community
        Indexing.html>

  GLOBALS (Scalar Methods)
    These are methods to return scalar data from RFC1213.

    Some subset of these is probably available for any network device that
    speaks SNMP.

    $info->uptime()
        Uptime in hundredths of seconds since device became available.

        ("sysUpTime")

    $info->contact()
        ("sysContact")

    $info->name()
        ("sysName")

    $info->location()
        ("sysLocation")

    $info->layers()
        This returns a binary encoded string where each digit represents a
        layer of the OSI model served by the device.

            eg: 01000010  means layers 2 (physical) and 7 (Application)
                          are served.

        Note: This string is 8 digits long.

        See $info->has_layer()

        ("sysServices")

    $info->ports()
        Number of interfaces available on this device.

        Not too useful as the number of SNMP interfaces usually does not
        correspond with the number of physical ports

        ("ifNumber")

    $info->ipforwarding()
        The indication of whether the entity is acting as an IP gateway

        Returns either forwarding or not-forwarding

        ("ipForwarding")

  Table Methods
    Each of these methods returns a hash_reference to a hash keyed on the
    interface index in SNMP.

    Example : $info->interfaces() might return

        { '1.12' => 'FastEthernet/0',
          '2.15' => 'FastEthernet/1',
          '9.99' => 'FastEthernet/2'
        }

    The key is what you would see if you were to do an snmpwalk, and in some
    cases changes between reboots of the network device.

  Partial Table Fetches
    If you want to get only a part of an SNMP table or a single instance
    from the table and you know the IID for the part of the table that you
    want, you can specify it in the call:

        $local_routes = $info->ipr_route('192.168.0');

    This will only fetch entries in the table that start with 192.168.0,
    which in this case are routes on the local network.

    Remember that you must supply the partial IID (a numeric OID).

    Partial table results are not cached.

  Interface Information
    $info->interfaces()
        This methods is overridden in each subclass to provide a mapping
        between the Interface Table Index (iid) and the physical port name.

    $info->if_ignore()
        Returns a reference to a hash where key values that exist are
        interfaces to ignore.

        Ignored interfaces are ones that are usually not physical ports or
        Virtual Lans (VLANs) such as the Loopback interface, or the CPU
        interface.

    $info->bulkwalk_no()
        Returns 0. Is an overridable method used for turn off bulkwalk for
        the device class.

    $info->i_index()
        Default SNMP IID to Interface index.

        ("ifIndex")

    $info->i_description()
        Description of the interface. Usually a little longer single word
        name that is both human and machine friendly. Not always.

        ("ifDescr")

    $info->i_type()
        Interface type, such as Vlan, Ethernet, Serial

        ("ifType")

    $info->i_mtu()
        INTEGER. Interface MTU value.

        ("ifMtu")

    $info->i_speed()
        Speed of the link, human format. See munge_speed() later in document
        for details.

        ("ifSpeed", "ifHighSpeed" if necessary)

    $info->i_speed_raw()
        Speed of the link in bits per second without munging. If
        i_speed_high is available it will be used and multiplied by
        1_000_000.

        ("ifSpeed", "ifHighSpeed" if necessary)

    $info->i_speed_high()
        Speed of a high-speed link, human format. See munge_highspeed()
        later in document for details. You should not need to call this
        directly, as i_speed() will call it if it needs to.

        ("ifHighSpeed")

    $info->i_mac()
        MAC address of the interface. Note this is just the MAC of the port,
        not anything connected to it.

        ("ifPhysAddress")

    $info->i_up()
        Link Status of the interface. Typical values are 'up' and 'down'.

        ("ifOperStatus")

    $info->i_up_admin()
        Administrative status of the port. Typical values are 'enabled' and
        'disabled'.

        ("ifAdminStatus")

    $info->i_lastchange()
        The value of "sysUpTime" when this port last changed states
        (up,down).

        ("ifLastChange")

    $info->i_name()
        Interface Name field. Supported by a smaller subset of devices, this
        fields is often human set.

        ("ifName")

    $info->i_alias()
        Interface Name field. For certain devices this is a more human
        friendly form of i_description(). For others it is a human set field
        like i_name().

        ("ifAlias")

  Interface Statistics
    $info->i_octet_in(), $info->i_octet_out(), $info->i_octet_in64(),
    $info->i_octet_out64()
        Bandwidth.

        Number of octets sent/received on the interface including framing
        characters.

        64 bit version may not exist on all devices.

        NOTE: To manipulate 64 bit counters you need to use Math::BigInt,
        since the values are too large for a normal Perl scalar. Set the
        global $SNMP::Info::BIGINT to 1 , or pass the BigInt value to new()
        if you want SNMP::Info to do it for you.

        ("ifInOctets") ("ifOutOctets") ("ifHCInOctets") ("ifHCOutOctets")

    $info->i_errors_in(), $info->i_errors_out()
        Number of packets that contained an error preventing delivery. See
        "IF-MIB" for more info.

        ("ifInErrors") ("ifOutErrors")

    $info->i_pkts_ucast_in(), $info->i_pkts_ucast_out(),
    $info->i_pkts_ucast_in64(), $info->i_pkts_ucast_out64()
        Number of packets not sent to a multicast or broadcast address.

        64 bit version may not exist on all devices.

        ("ifInUcastPkts") ("ifOutUcastPkts") ("ifHCInUcastPkts")
        ("ifHCOutUcastPkts")

    $info->i_pkts_nucast_in(), $info->i_pkts_nucast_out(),
        Number of packets sent to a multicast or broadcast address.

        These methods are deprecated by i_pkts_multi_in() and
        i_pkts_bcast_in() according to "IF-MIB". Actual device usage may
        vary.

        ("ifInNUcastPkts") ("ifOutNUcastPkts")

    $info->i_pkts_multi_in() $info->i_pkts_multi_out(),
    $info->i_pkts_multi_in64(), $info->i_pkts_multi_out64()
        Number of packets sent to a multicast address.

        64 bit version may not exist on all devices.

        ("ifInMulticastPkts") ("ifOutMulticastPkts") ("ifHCInMulticastPkts")
        ("ifHCOutMulticastPkts")

    $info->i_pkts_bcast_in() $info->i_pkts_bcast_out(),
    $info->i_pkts_bcast_in64() $info->i_pkts_bcast_out64()
        Number of packets sent to a broadcast address on an interface.

        64 bit version may not exist on all devices.

        ("ifInBroadcastPkts") ("ifOutBroadcastPkts") ("ifHCInBroadcastPkts")
        ("ifHCOutBroadcastPkts")

    $info->i_discards_in() $info->i_discards_out()
        "The number of inbound packets which were chosen to be discarded
        even though no errors had been detected to prevent their being
        deliverable to a higher-layer protocol. One possible reason for
        discarding such a packet could be to free up buffer space."
        ("IF-MIB")

        ("ifInDiscards") ("ifOutDiscards")

    $info->i_bad_proto_in()
        "For packet-oriented interfaces, the number of packets received via
        the interface which were discarded because of an unknown or
        unsupported protocol. For character-oriented or fixed-length
        interfaces that support protocol multiplexing the number of
        transmission units received via the interface which were discarded
        because of an unknown or unsupported protocol. For any interface
        that does not support protocol multiplexing, this counter will
        always be 0."

        ("ifInUnknownProtos")

    $info->i_qlen_out()
        "The length of the output packet queue (in packets)."

        ("ifOutQLen")

    $info->i_specific()
        See "IF-MIB" for full description

        ("ifSpecific")

  IPv4 Address Table
    Each entry in this table is an IPv4 address in use on this device.
    Usually this is implemented in Layer3 Devices. These methods try the
    deprecated IPv4 address table "IP-MIB::ipAddrTable" first due to its
    prevalence and will try the current "IP-MIB::ipAddressTable" if it
    doesn't return any results. "IP-MIB::ipAddressTable" results are
    filtered to only return IPv4 unicast addresses and modified to match the
    return format of the older table for backwards compatibility.

    See documentation in SNMP::Info::IPv6 for IPv6 Address Table.

    $info->ip_index()
        Maps the IPv4 addresses to the interface index

        ("ipAdEntIfIndex") or filtered and index modified
        ("ipAddressIfIndex")

    $info->ip_table()
        Maps the Table to the IPv4 address

        ("ipAdEntAddr") or address extracted from ("ipAddressIfIndex")

    $info->ip_netmask()
        Gives netmask setting for IPv4 table entry.

        ("ipAdEntNetMask") or netmask calculated from ("ipAddressPrefix")

    $info->ip_broadcast()
        Gives the value of the least-significant bit in the IPv4 broadcast
        address either 1 or 0.

        ("ipAdEntBcastAddr"), there is no equivalent from the
        "IP-MIB::ipAddressTable"

  IP Routing Table
    $info->ipr_route()
        The route in question. A value of 0.0.0.0 is the default gateway
        route.

        ("ipRouteDest")

    $info->ipr_if()
        The interface (IID) that the route is on. Use interfaces() to map.

        ("ipRouteIfIndex")

    $info->ipr_1()
        Primary routing metric for this route.

        ("ipRouteMetric1")

    $info->ipr_2()
        If metrics are not used, they should be set to -1

        ("ipRouteMetric2")

    $info->ipr_3()
        ("ipRouteMetric3")

    $info->ipr_4()
        ("ipRouteMetric4")

    $info->ipr_5()
        ("ipRouteMetric5")

    $info->ipr_dest()
        From RFC1213:

          "The IP address of the next hop of this route.
          (In the case of a route bound to an interface
          which is realized via a broadcast media, the value
          of this field is the agent's IP address on that
          interface.)"

        ("ipRouteNextHop")

    $info->ipr_type()
        From RFC1213:

            other(1),        -- none of the following
            invalid(2),      -- an invalidated route
                             -- route to directly
            direct(3),       -- connected (sub-)network
                             -- route to a non-local
            indirect(4)      -- host/network/sub-network


              "The type of route.  Note that the values
              direct(3) and indirect(4) refer to the notion of
              direct and indirect routing in the IP
              architecture.

              Setting this object to the value invalid(2) has
              the effect of invalidating the corresponding entry
              in the ipRouteTable object.  That is, it
              effectively disassociates the destination
              identified with said entry from the route
              identified with said entry.  It is an
              implementation-specific matter as to whether the
              agent removes an invalidated entry from the table.
              Accordingly, management stations must be prepared
              to receive tabular information from agents that
              corresponds to entries not currently in use.
              Proper interpretation of such entries requires
              examination of the relevant ipRouteType object."

        ("ipRouteType")

    $info->ipr_proto()
        From RFC1213:

            other(1),       -- none of the following
                            -- non-protocol information,
                            -- e.g., manually configured
            local(2),       -- entries
                            -- set via a network
            netmgmt(3),     -- management protocol
                            -- obtained via ICMP,
            icmp(4),        -- e.g., Redirect
                            -- the remaining values are
                            -- all gateway routing
                            -- protocols
            egp(5),
            ggp(6),
            hello(7),
            rip(8),
            is-is(9),
            es-is(10),
            ciscoIgrp(11),
            bbnSpfIgp(12),
            ospf(13),
            bgp(14)

        ("ipRouteProto")

    $info->ipr_age()
        Seconds since route was last updated or validated.

        ("ipRouteAge")

    $info->ipr_mask()
        Subnet Mask of route. 0.0.0.0 for default gateway.

        ("ipRouteMask")

    $info->ipr_info()
        Reference to MIB definition specific to routing protocol.

        ("ipRouteInfo")

  Topology Information
    Based upon the manufacturer and software version devices may support
    some combination of Layer 2 topology protocol information. SNMP::Info
    supports querying Link Layer Discovery Protocol (LLDP), Cisco Discovery
    Protocol (CDP), SynOptics/Bay/Nortel/Avaya Network Management Protocol
    (SONMP), Foundry/Brocade Discovery Protocol (FDP), Extreme Discovery
    Protocol (EDP), and Alcatel Mapping Adjacency Protocol (AMAP).

    For protocol specific information and implementation:

    AMAP: See SNMP::Info::AMAP for details.
    CDP: See SNMP::Info::CDP for details.
    EDP: See SNMP::Info::EDP for details.
    FDP: See SNMP::Info::FDP for details.
    LLDP: See SNMP::Info::LLDP for details.
    SONMP: See SNMP::Info::SONMP for details.

   Topology Capabilities
    $info->has_topo()
        Reports Layer 2 topology protocols which are supported and running
        on a device.

        Returns either a reference to an array of protocols, possible values
        being: "lldp", "cdp", "sonmp", "fdp", "edp", "amap" or "undef" if no
        protocols are supported or running.

   Common Topology Table Information
    The common topology table methods below will query the device for
    information from the specified topology protocols and return a single
    hash combining all information. As a result, there may be identical
    topology information returned from the two protocols causing duplicate
    entries. It is the calling program's responsibility to identify any
    duplicate entries and remove duplicates if necessary. If it is necessary
    to understand which protocol provided the information, utilize the
    protocol specific methods directly rather than the generic methods.

    The methods support partial table fetches by providing a partial as the
    first argument.

    If a reference to an array is provided as the second argument, those
    protocols will be queried for information. The supported array values
    are: "lldp", "cdp", "sonmp", "fdp", "edp", "amap".

    If nothing is passed in as the second argument, the methods will call
    has_topo() to determine supported and running topology protocols on the
    device.

    $info->c_ip(partial, topology_protocol_arrayref)
        Returns reference to hash. Key: iid, Value: remote IPv4 address

        If multiple entries exist with the same local port, c_if(), with the
        same IPv4 address, c_ip(), it may be a duplicate entry.

        If multiple entries exist with the same local port, c_if(), with
        different IPv4 addresses, c_ip(), there is either a device in
        between two or more devices utilizing a different topology protocol
        or multiple devices which are not directly connected.

        Use the protocol specific methods to dig deeper.

    $info->c_if(partial, topology_protocol_arrayref)
        Returns reference to hash. Key: iid, Value: local device port
        (interfaces)

    $info->c_port(partial, topology_protocol_arrayref)
        Returns reference to hash. Key: iid, Value: remote port (interfaces)

    $info->c_id(partial, topology_protocol_arrayref)
        Returns reference to hash. Key: iid, Value: string value used to
        identify the chassis component associated with the remote system.

        Note: SONMP does not return this information.

    $info->c_platform(partial, topology_protocol_arrayref)
        Returns reference to hash. Key: iid, Value: Remote Device Type

        Note: EDP does not provide this information. LLDP uses
        ("lldpRemSysDesc") or "lldp_rem_sysname" as the closest match.

    $info->c_cap(partial, topology_protocol_arrayref)
        Returns reference to hash of arrays. Key: iid, Value: Array of
        capabilities supported by the device. See the specific protocol
        class for string values which could be elements within the array.

        Note: Only CDP and LLDP support this method.

SETTING DATA VIA SNMP
    This section explains how to use SNMP::Info to do SNMP Set operations.

    $info->set_METHOD($value)
        Sets the global METHOD to value. Assumes that iid is .0

        Returns if failed, or the return value from SNMP::Session::set()
        (snmp_errno)

         $info->set_location("Here!");

    $info->set_METHOD($value,$iid)
        Table Methods. Set iid of method to value.

        Returns if failed, or the return value from SNMP::Session::set()
        (snmp_errno)

         # Disable a port administratively
         my %if_map = reverse %{$info->interfaces()}
         $info->set_i_up_admin('down', $if_map{'FastEthernet0/0'})
            or die "Couldn't disable the port. ",$info->error(1);

    NOTE: You must be connected to your device with a "ReadWrite" community
    string in order for set operations to work.

    NOTE: This will only set data listed in %FUNCS and %GLOBALS. For data
    acquired from overridden methods (subroutines) specific set_METHOD()
    subroutines will need to be added if they haven't been already.

Quiet Mode
    SNMP::Info will not chirp anything to STDOUT unless there is a serious
    error (in which case it will probably die).

    To get lots of debug info, set the Debug flag when calling new() or call
    $info->debug(1);

    When calling a method check the return value. If the return value is
    undef then check $info->error()

    Beware, calling $info->error() clears the error.

     my $name = $info->name() or die "Couldn't get sysName!" . $name->error();

EXTENDING SNMP::INFO
    To support a new class (vendor or platform) of device, add a Perl
    package with the data structures and methods listed below.

    If this seems a little scary, then the SNMP::Info developers are usually
    happy to accept the SNMP data from your device and make an attempt at
    the class themselves. Usually a "beta" release will go to CPAN for you
    to verify the implementation.

  Gathering MIB data for SNMP::Info Developers
    The preference is to open a pull request in the github project. This
    allows all developers to have visibility into the request. Please
    include pointers to the applicable platform MIBs. For development we
    will need an "snmpwalk" of the device. There is a tool now included in
    the SNMP::Info distribution to help with this task, although you'll most
    likely need to download the distribution from CPAN as it's included in
    the ""contrib/util"" directory.

    The utility is named "make_snmpdata.pl". Run it with a command line
    like:

     ./make_snmpdata.pl -c community -i -d device_ip \
      -m /home/netdisco-mibs/rfc:/home/netdisco-mibs/net-snmp:/home/netdisco-mibs/dir3 \
      SNMPv2-MIB IF-MIB EtherLike-MIB BRIDGE-MIB Q-BRIDGE-MIB ENTITY-MIB \
      POWER-ETHERNET-MIB IPV6-MIB LLDP-MIB DEVICE-SPECIFIC-MIB-NAME(s) > output.txt

    This will print to the file every MIB entry with data in a format that
    the developers can use to emulate read operations without needing access
    to the device. Preference would be to mask any sensitive data in the
    output, zip the file, and attach it to the github pull request. However,
    if you do not feel comfortable uploading the output to the tracker you
    could e-mail it to the developer that has claimed the ticket.

  Data Structures required in new Subclass
    A class inheriting this class must implement these data structures :

    $INIT
        Used to flag if the MIBs have been loaded yet.

    %GLOBALS
        Contains a hash in the form ( method_name => SNMP MIB leaf name )
        These are scalar values such as name, uptime, etc.

        To resolve MIB leaf name conflicts between private MIBs, you may
        prefix the leaf name with the MIB replacing each - (dash) and :
        (colon) with an _ (underscore). For example,
        ALTEON_TIGON_SWITCH_MIB__agSoftwareVersion would be used as the hash
        value instead of the net-snmp notation
        ALTEON-TIGON-SWITCH-MIB::agSoftwareVersion.

        When choosing the name for the methods, be aware that other new Sub
        Modules might inherit this one to get it's features. Try to choose a
        prefix for methods that will give it's own name space inside the
        SNMP::Info methods.

    %FUNCS
        Contains a hash in the form ( method_name => SNMP MIB leaf name)
        These are table entries, such as the "ifIndex"

        To resolve MIB leaf name conflicts between private MIBs, you may
        prefix the leaf name with the MIB replacing each - (dash) and :
        (colon) with an _ (underscore). For example,
        ALTEON_TS_PHYSICAL_MIB__agPortCurCfgPortName would be used as the
        hash value instead of the net-snmp notation
        ALTEON-TS-PHYSICAL-MIB::agPortCurCfgPortName.

    %MIBS
        A list of each mib needed.

            ('MIB-NAME' => 'itemToTestForPresence')

        The value for each entry should be a MIB object to check for to make
        sure that the MIB is present and has loaded correctly.

        $info->init() will throw an exception if a MIB does not load.

    %MUNGE
        A map between method calls (from %FUNCS or %GLOBALS) and subroutine
        methods. The subroutine called will be passed the data as it gets it
        from SNMP and it should return that same data in a more human
        friendly format.

        Sample %MUNGE:

         (my_ip     => \&munge_ip,
          my_mac    => \&munge_mac,
          my_layers => \&munge_dec2bin
         )

  Sample Subclass
    Let's make a sample Layer 2 Device subclass. This class will inherit the
    Cisco Vlan module as an example.

    ----------------------- snip --------------------------------

     # SNMP::Info::Layer2::Sample

     package SNMP::Info::Layer2::Sample;

     $VERSION = 0.1;

     use strict;
     use warnings;

     use Exporter;
     use SNMP::Info::Layer2;
     use SNMP::Info::CiscoVTP;

     @SNMP::Info::Layer2::Sample::ISA = qw/SNMP::Info::Layer2
                                           SNMP::Info::CiscoVTP Exporter/;
     @SNMP::Info::Layer2::Sample::EXPORT_OK = qw//;

     our ($VERSION, %FUNCS, %GLOBALS, %MIBS, %MUNGE, $AUTOLOAD, $INIT, $DEBUG);

     %MIBS    = (%SNMP::Info::Layer2::MIBS,
                 %SNMP::Info::CiscoVTP::MIBS,
                 'SUPER-DOOPER-MIB'  => 'supermibobject',
                );

     %GLOBALS = (%SNMP::Info::Layer2::GLOBALS,
                 %SNMP::Info::CiscoVTP::GLOBALS,
                 'name'              => 'supermib_supername',
                 'favorite_color'    => 'supermib_fav_color_object',
                 'favorite_movie'    => 'supermib_fav_movie_val',
                 );

     %FUNCS   = (%SNMP::Info::Layer2::FUNCS,
                 %SNMP::Info::CiscoVTP::FUNCS,
                 # Super Dooper MIB - Super Hero Table
                 'super_hero_index'  => 'SuperHeroIfIndex',
                 'super_hero_name'   => 'SuperHeroIfName',
                 'super_hero_powers' => 'SuperHeroIfPowers',
                );


     %MUNGE   = (%SNMP::Info::Layer2::MUNGE,
                 %SNMP::Info::CiscoVTP::MUNGE,
                 'super_hero_powers' => \&munge_powers,
                );

     # Override uptime() method from %SNMP::Info::GLOBALS
     sub uptime {
         my $sample = shift;

         my $name   = $sample->name();

         # this is silly but you get the idea
         return '600' if defined $name ;
     }

     # Create our own munge function
     sub munge_powers {
         my $power = shift;

         # Take the returned obscure value and return something useful.
         return 'Fire' if $power =~ /reallyhot/i;
         return 'Ice'  if $power =~ /reallycold/i;

         # Else
         return $power;
     }

     # Copious Documentation here!!!
     =head1 NAME
     =head1 AUTHOR
     =head1 SYNOPSIS
     =head1 DESCRIPTION
     =head2 Inherited Classes
     =head2 Required MIBs
     =head1 GLOBALS
     =head2 Overrides
     =head1 TABLE METHODS
     =head2 Overrides
     =cut

     1; # don't forget this line
    ----------------------- snip --------------------------------

SNMP::INFO INTERNALS
  Object Namespace
    Internal data is stored with bareword keys. For example $info->{debug}

    SNMP Data is stored or marked cached with keys starting with an
    underscore. For example $info->{_name} is the cache for $info->name().

    Cached Table data is stored in $info->store() and marked cached per
    above.

  Package Globals
    These set the default value for an object upon creation.

    $DEBUG
        Default 0. Sends copious debug info to stdout. This global sets the
        object's debug status in new() unless 'Debug' argument passed in
        new(). Change objects' debug status with $info->debug().

    $BIGINT
        Default 0. Set to true to have 64 bit counters return Math::BigInt
        objects instead of scalar string values. See note under Interface
        Statistics about 64 bit values.

    $NOSUCH
        Default 1. Set to false to disable RetryNoSuch option for
        SNMP::Session. Or see method in new() to do it on an object scope.

    $REPEATERS
        Default 20. MaxRepeaters for BULKWALK operations. See "perldoc SNMP"
        for more info. Can change by passing "BulkRepeaters" option in new()

  Data Munging Callback Subroutines
    munge_speed()
        Makes human friendly speed ratings using %SPEED_MAP.

         %SPEED_MAP = (
                        '56000'      => '56 kbps',
                        '64000'      => '64 kbps',
                        '115000'     => '115 kbps',
                        '1500000'    => '1.5 Mbps',
                        '1536000'    => 'T1',
                        '1544000'    => 'T1',
                        '2000000'    => '2.0 Mbps',
                        '2048000'    => '2.048 Mbps',
                        '3072000'    => 'Dual T1',
                        '3088000'    => 'Dual T1',
                        '4000000'    => '4.0 Mbps',
                        '10000000'   => '10 Mbps',
                        '11000000'   => '11 Mbps',
                        '16000000'   => '16 Mbps',
                        '16777216'   => '16 Mbps',
                        '20000000'   => '20 Mbps',
                        '44210000'   => 'T3',
                        '44736000'   => 'T3',
                        '45000000'   => '45 Mbps',
                        '45045000'   => 'DS3',
                        '46359642'   => 'DS3',
                        '51850000'   => 'OC-1',
                        '54000000'   => '54 Mbps',
                        '64000000'   => '64 Mbps',
                        '100000000'  => '100 Mbps',
                        '149760000'  => 'ATM on OC-3',
                        '155000000'  => 'OC-3',
                        '155519000'  => 'OC-3',
                        '155520000'  => 'OC-3',
                        '200000000'  => '200 Mbps',
                        '400000000'  => '400 Mbps',
                        '599040000'  => 'ATM on OC-12',
                        '622000000'  => 'OC-12',
                        '622080000'  => 'OC-12',
                        '1000000000' => '1.0 Gbps',
                        '2000000000' => '2.0 Gbps',
                        '2488000000' => 'OC-48',
                        '2500000000' => '2.5 Gbps',
                     )

        Note: high speed interfaces (usually 1 Gbps or faster) have their
        link speed in "ifHighSpeed". i_speed() automatically determines
        whether to use "ifSpeed" or "ifHighSpeed"; if the latter is used,
        the value is munged by munge_highspeed(). SNMP::Info can return
        speeds up to terabit levels this way.

    munge_highspeed()
        Makes human friendly speed ratings for "ifHighSpeed".

    munge_ip()
        Takes a binary IP and makes it dotted ASCII.

    munge_inetaddress()
        Takes a binary IP address as defined by the SNMP InetAddress type
        and returns it as human readable string.

    munge_mac()
        Takes an octet stream (HEX-STRING) and returns a colon separated
        ASCII hex string.

    munge_prio_mac()
        Takes an 8-byte octet stream (HEX-STRING) and returns a colon
        separated ASCII hex string.

    munge_prio_port()
        Takes an 2-byte octet stream (HEX-STRING) and returns a colon
        separated ASCII hex string.

    munge_octet2hex()
        Takes a binary octet stream and returns an ASCII hex string.

    munge_dec2bin()
        Takes a binary char and returns its ASCII binary representation.

    munge_bits()
        Takes a SNMP2 'BITS' field and returns the ASCII bit string.

    munge_counter64()
        If $BIGINT is set to true, then a Math::BigInt object is returned.
        See Math::BigInt for details.

    munge_i_up()
        Net-SNMP tends to load "RFC1213-MIB" first, and so ignores the
        updated enumeration for "ifOperStatus" in "IF-MIB". This munge
        handles the "newer" definitions for the enumeration in IF-MIB.

        TODO: Get the precedence of MIBs and overriding of MIB data in
        Net-SNMP figured out. Hierarchy/precedence of MIBS in SNMP::Info.

    munge_port_list()
        Takes an octet string representing a set of ports and returns a
        reference to an array of binary values each array element
        representing a port.

        If the element has a value of '1', then that port is included in the
        set of ports; the port is not included if it has a value of '0'.

    munge_null()
        Removes control characters from a string.

    munge_e_type()
        Takes an OID and return the object name if the right MIB is loaded.

  Internally Used Functions
    resolve_desthost()
        Takes the SNMP::Session "DestHost" argument and determines if it is
        an 'IPv4' or 'IPv6' host. 'IPv6' hosts are prefixed with the "udp6:"
        "transport-specifier" as required by the underlying "Net-SNMP"
        library. If unable to determine the type of address or resolve a DNS
        name, dies with "croak".

    $info->init()
        Used internally. Loads all entries in %MIBS.

    $info->args()
        Returns a reference to the argument hash supplied to SNMP::Session

    $info->class()
        Returns the class name of the object.

    $info->error_throw(error message)
        Stores the error message for use by $info->error()

        If $info->debug() is true, then the error message is carped too.

    $info->funcs()
        Returns a reference to the %FUNCS hash.

    $info->globals()
        Returns a reference to the %GLOBALS hash.

    $info->mibs()
        Returns a reference to the %MIBS hash.

    $info->munge()
        Returns a reference of the %MUNGE hash.

    $info->nosuch()
        Returns NoSuch value set or not in new()

    $info->session()
        Gets or Sets the SNMP::Session object.

    $info->store(new_store)
        Returns or sets hash store for Table functions.

        Store is a hash reference in this format :

        $info->store = { attribute => { iid => value , iid2 => value2, ... }
        };

    $info->_global()
        Used internally by AUTOLOAD to create dynamic methods from %GLOBALS
        or a single instance MIB Leaf node name from a loaded MIB.

        Example: $info->name() on the first call dispatches to AUTOLOAD()
        which calls $info->_global('name') creating the method name().

        These methods return data as a scalar.

    $info->_set(attr,val,iid,type)
        Used internally by set_multi() to run an SNMP set command. When run
        clears attr cache.

        Attr can be passed as either a scalar or a reference to an array or
        array of arrays when used with set_multi().

        Example: $info->set_name('dog',3) uses autoload to resolve to
        $info->_set('name','dog',3);

    $info->_make_setter(val,iid)
        Used internally by AUTOLOAD to create dynamic methods from either
        %GLOBALS, %FUNCS, or a valid mib leaf from a loaded MIB which runs
        an SNMP set command. When run clears the attribute cache.

        Example: $info->set_name('dog',3) dispatches to autoload to resolve
        to $info->_set('name','dog',3) and _make_setter creates the
        set_name() method.

    $info->set_multi(arrayref)
        Used to run an SNMP set command on several new values in the one
        request. Returns the result of $info->_set(method).

        Pass either a reference to a 4 element array [<obj>, <iid>, <val>,
        <type>] or a reference to an array of 4 element arrays to specify
        multiple values.

            <obj> - One of the following forms:
                1) leaf identifier (e.g., C<'sysContact'>)
                2) An entry in either %FUNCS, %GLOBALS (e.g., 'contact')
            <iid> - The dotted-decimal, instance identifier. For scalar MIB objects
                     use '0'
            <val>  - The SNMP data value being set (e.g., 'netdisco')
            <type> - Optional as the MIB should be loaded.

        If one of the set assignments is invalid, then the request will be
        rejected without applying any of the new values - regardless of the
        order they appear in the list.

        Example: my $vlan_set = [
        ['qb_v_untagged',"$old_vlan_id","$old_untagged_portlist"],
        ['qb_v_egress',"$new_vlan_id","$new_egress_portlist"],
        ['qb_v_egress',"$old_vlan_id","$old_egress_portlist"],
        ['qb_v_untagged',"$new_vlan_id","$new_untagged_portlist"],
        ['qb_i_vlan',"$port","$new_vlan_id"], ];

            $info->set_multi($vlan_set);

    $info->load_all()
        Debugging routine. This does not include any overridden method or
        method implemented by subroutine.

        Runs $info->load_METHOD() for each entry in $info->funcs();

        Returns $info->store() -- See store() entry.

        Note return value has changed since version 0.3

    $info->all()
        Runs $info->load_all() once then returns $info->store();

        Use $info->load_all() to reload the data.

        Note return value has changed since version 0.3

    $info->_load_attr()
        Used internally by AUTOLOAD to create dynamic methods from %FUNCS or
        a MIB Leaf node name contained within a table of a loaded MIB.

        Supports partial table fetches and single instance table fetches.
        See "Partial Table Fetches" in SNMP::Info.

        These methods return data as a reference to a hash.

    $info->_show_attr()
        Used internally by AUTOLOAD to return data called by methods listed
        in %FUNCS.

    $info->snmp_connect_ip(ip)
        Returns true or false based upon snmp connectivity to an IP.

    modify_port_list(portlist,offset,replacement)
        Replaces the specified bit in a port_list array and returns the
        packed bitmask

    $info->_cache(attr, data)
        Cache retrieved data so that if it's asked for again, we use the
        cache instead of going back to Net-SNMP. Data is cached inside the
        blessed hashref $self.

        Accepts the leaf and value (scalar, or hashref for a table). Does
        not return anything useful.

    $info->_munge(attr, data)
        Raw data returned from Net-SNMP might not be formatted correctly or
        might have platform-specific bugs or mistakes. The MUNGE feature of
        SNMP::Info allows for fixups to take place.

        Accepts the leaf and value (scalar, or hashref for a table) and
        returns the raw or the munged data, as appropriate. That is, you do
        not need to know whether MUNGE is installed, and it's safe to call
        this method regardless.

    _validate_autoload_method(method)
        Used internally by AUTOLOAD to validate that a dynamic method should
        be created. Returns the OID of the MIB leaf node the method will get
        or set.

        1. Returns unless method is listed in %FUNCS, %GLOBALS, or is MIB
        Leaf node name in a loaded MIB for given class.
        2. Translates the MIB Leaf node name to an OID.
        3. Checks to see if the method access type is allowed for the
        resolved OID. Write access for set_ methods, read access for others.

    $info->can()
        Overrides UNIVERSAL::can() so that objects will correctly report
        their capabilities to include dynamic methods generated at run time
        via AUTOLOAD.

        Calls parent can() first to see if method exists, if not validates
        that a method should be created then dispatches to the appropriate
        internal method for creation.

        Returns undef if the method does not exist and can not be created.

  AUTOLOAD
    Each entry in either %FUNCS, %GLOBALS, or MIB Leaf node names present in
    loaded MIBs are used by AUTOLOAD() to create dynamic methods.

    1. Returns unless method is listed in %FUNCS, %GLOBALS, or is a MIB Leaf
    node name in a loaded MIB for given class.
    2. If the method exists in %GLOBALS or is a single instance MIB Leaf
    node name from a loaded MIB, _global() generates the method.
    3. If a set_ prefix is present _make_setter() generates the method.
    4. If the method exists in %FUNCS or is a MIB Leaf node name contained
    within a table from a loaded MIB, _load_attr() generates the method.
    5. A load_ prefix forces reloading of data and does not use cached data.
    6. A _raw suffix returns data ignoring any munge routines.

    Override any dynamic method listed in %GLOBALS, %FUNCS, or MIB Leaf node
    name a by creating a subroutine with the same name.

    For example to override $info->name() create `` sub name {...}'' in your
    subclass.

COPYRIGHT AND LICENSE
    Changes from SNMP::Info Version 0.7 and on are: Copyright (c) 2003-2010
    Max Baker and SNMP::Info Developers All rights reserved.

    Original Code is: Copyright (c) 2002-2003, Regents of the University of
    California All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

        * Redistributions of source code must retain the above copyright notice,
          this list of conditions and the following disclaimer.
        * Redistributions in binary form must reproduce the above copyright
          notice, this list of conditions and the following disclaimer in the
          documentation and/or other materials provided with the distribution.
        * Neither the name of the University of California, Santa Cruz nor the
          names of its contributors may be used to endorse or promote products
          derived from this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
    IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
    TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
    PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.