SNMP::...Layer3(3pm)

📦
version 3.975000 · 8 versions
, in ubuntu stonking

💖 SNMP::Info::Layer3 💖

okay bestie, welcome to SNMP::Info::Layer3, like the third layer of a cake but make it network devices 🎂✨ it's shipped as part of the User Contributed Perl Documentation and it lives at SNMP::...Layer3(3pm) in your man pages, no cap.

✨ NAME ✨

SNMP::Info::Layer3 — the SNMP Interface to network devices serving Layer3 or Layers 2 & 3 🫶

👑 AUTHOR 👑

Max Baker

🌸 SYNOPSIS 🌸

okay so here's the whole vibe, copy it, don't improvise:

 # Let SNMP::Info determine the correct subclass for you.
 my $l3 = new SNMP::Info(
                          AutoSpecify => 1,
                          Debug       => 1,
                          DestHost    => 'myswitch',
                          Community   => 'public',
                          Version     => 2
                        )
    or die "Can't connect to DestHost.\n";

 my $class = $l3->class();
 print "SNMP::Info determined this device to fall under subclass : $class\n";

 # Let's get some basic Port information
 my $interfaces = $l3->interfaces();
 my $i_up       = $l3->i_up();
 my $i_speed    = $l3->i_speed();
 foreach my $iid (keys %$interfaces) {
    my $port  = $interfaces->{$iid};
    my $up    = $i_up->{$iid};
    my $speed = $i_speed->{$iid}
    print "Port $port is $up. Port runs at $speed.\n";
 }

look at her go 💅

🦋 DESCRIPTION 🦋

ngl this class is almost always the superclass situation — more specific device classes under SNMP::Info::Layer3::* inherit from it 💜 so pls pls pls read all the docs under SNMP::Info first, i'm begging.

It gives you generic methods for pulling SNMP data out of Layer 3 network devices, and yes it also handles Layer2+3 devices, we love an overachiever 🔥

If you're doing it for speed or for debugging, you can call the subclass directly — but not after you've already used the method up there to figure out a more specific class, that's the rule bestie 🚫

 my $l3 = new SNMP::Info::Layer3(...);

🧬 Inherited Classes

  • SNMP::Info
  • SNMP::Info::Bridge (For L2/L3 devices)
  • SNMP::Info::EtherLike
  • SNMP::Info::Entity
  • SNMP::Info::PowerEthernet
  • SNMP::Info::IPv6
  • SNMP::Info::LLDP
  • SNMP::Info::DocsisHE
  • SNMP::Info::AdslLine

family tree is giving ✨royalty✨

📚 Required MIBs

  • IP-MIB
  • ISIS-MIB
  • OSPF-MIB
  • BGP4-MIB

🌈 Inherited MIBs

these ones aren't ours, they come from the ancestors, go read their requirements:

  • See "REQUIREMENTS" in SNMP::Info for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::Bridge for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::EtherLike for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::Entity for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::PowerEthernet for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::IPv6 for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::LLDP for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::DocsisHE for its MIB requirements.
  • See "Required MIBs" in SNMP::Info::AdslLine for its MIB requirements.

⭐ GLOBALS ⭐

these are the methods that return a scalar value straight out of SNMP, simple as, periodt.

  • $l3->mac() — returns the root port mac address 🎀
    • ("ifPhysAddress.1")
  • $l3->router_ip() — grabs it from here:
    • ("ospfRouterId.0")
  • $l3->bgp_id() — comes from ("bgpIdentifier.0")
    • Returns the BGP identifier of the local system
  • $l3->bgp_local_as() — Returns the local autonomous system number 🫶
    • ("bgpLocalAs.0")

💅 Overrides

these are the ones Layer3 rewrites to do its own thing, main character energy only.

  • $l3->model() — tries to reference $l3->id() to one of the product MIBs listed above 🧚
    • Removes 'cisco' from cisco devices for readability. (so it doesn't read like a brand ad, we get it)
  • $l3->serial() — Returns a serial number if found from ENTITY-MIB and OLD-CISCO-... MIB.
  • $l3->vendor() — Tries to cull a Vendor name from "sysDescr"
  • $l3->root_ip() — Returns the primary IP used to communicate with the device. Returns the first found: OSPF Router ID ("ospfRouterId") or any OSPF Host IP Address ("ospfHostIpAddress"). first come first served bestie 😌

🍓 Globals imported from SNMP::Info

See "USAGE" in SNMP::Info for details.

🌸 Global Methods imported from SNMP::Info::Bridge

See "GLOBALS" in SNMP::Info::Bridge for details.

💜 Global Methods imported from SNMP::Info::EtherLike

See "GLOBALS" in SNMP::Info::EtherLike for details.

✨ Global Methods imported from SNMP::Info::Entity

See "GLOBALS" in SNMP::Info::Entity for details.

🎀 Global Methods imported from SNMP::Info:PowerEthernet

See "GLOBALS" in SNMP::Info::PowerEthernet for details.

🦋 Global Methods imported from SNMP::Info::IPv6

See "GLOBALS" in SNMP::Info::IPv6 for details.

🔥 Global Methods imported from SNMP::Info::LLDP

See "GLOBALS" in SNMP::Info::LLDP for details.

🌈 Global Methods imported from SNMP::Info::DocsisHE

See "GLOBALS" in SNMP::Info::DocsisHE for details.

💖 Global Methods imported from SNMP::Info::AdslLine

See "GLOBALS" in SNMP::Info::AdslLine for details.

📊 TABLE METHODS 📊

okay bestie, these are the methods that hand you back tables of info, and the format is always the same: a reference to a hash. slay. 💅

🎀 Overrides 🎀

  • $l3->interfaces() — gives you the map between the SNMP Interface Identifier (iid) and the physical port name. 💖

But heads up, queen: it only returns those iids that have a description listed in $l3->i_description(). no description, no entry. that's the vibe check. ✨

  • $l3->i_subinterfaces() — hands you a reference to a hash of arrays, where key = "ifIndex" and value = array of "ifIndex". these are the VLAN subinterfaces ("l2vlan" type) hanging off their parent ("ethernetCsmacd" type) interface. it's giving family tree. 🌳

Example:

my $interfaces = $l3->interfaces();
my $i_subs     = $l3->i_subinterfaces();

foreach my $iid (sort keys %$interfaces) {
  my $port = $interfaces->{$iid};
  my $subs = join(',', sort(map {$interfaces->{$_}} @{$i_subs->{$iid}}));
  print "Port: $port has subinterfaces: $subs\n";
}
  • $l3->i_name() — reference to hash of iid ➡️ human set name. 🫶

Defaults to "ifName", but it checks for an "ifAlias" first. lowkey picky, highkey correct.

  • $l3->i_duplex() — reference to hash of iid ➡️ current link duplex setting.

What it does: maps $l3->el_index() to $l3->el_duplex, then culls out full, half, or auto and sets the map to that value. culling era. ✂️

Peep SNMP::Info::EtherLike for the el_index() and el_duplex() methods. iykyk.

🌐 IP-MIB Arp Cache Table ("ipNetToMediaTable") 🌐

  • $l3->at_index() — reference to hash. maps ARP table entries to Interface IIDs ("ipNetToMediaIfIndex").

If the device doesn't support "ipNetToMediaIfIndex", it'll try the deprecated "atIfIndex" instead. backup plan energy. 🙈

  • $l3->at_paddr() — reference to hash. maps ARP table entries to MAC addresses ("ipNetToMediaPhysAddress").

If the device doesn't support "ipNetToMediaPhysAddress", it'll try the deprecated "atPhysAddress".

  • $l3->at_netaddr() — reference to hash. maps ARP table entries to IP addresses ("ipNetToMediaNetAddress").

If the device doesn't support "ipNetToMediaNetAddress", it'll try the deprecated "atNetAddress".

👵 ARP Cache Entries 👵

bestie. listen. the "atTable" has been deprecated since 1991. you should never need to use these methods. like, that's older than most of us. see "ipNetToMediaTable" above instead, fr fr. 💀
  • $l3->old_at_index() — reference to map of IID to Arp Cache Entry ("atIfIndex").
  • $l3->old_at_paddr() — reference to hash of Arp Cache Entries to MAC address ("atPhysAddress").
  • $l3->old_at_netaddr() — reference to hash of Arp Cache Entries to IP Address ("atNetAddress").

🛰️ BGP Peer Table ("bgpPeerTable") 🛰️

  • $l3->bgp_peers() — reference to hash of BGP peer ➡️ local IP address ("bgpPeerLocalAddr").
  • $l3->bgp_peer_id() — reference to hash of BGP peer ➡️ BGP peer identifier ("bgpPeerIdentifier").
  • $l3->bgp_peer_state() — reference to hash of BGP peer ➡️ BGP peer state ("bgpPeerState").
  • $l3->bgp_peer_as() — reference to hash of BGP peer ➡️ BGP peer autonomous system number ("bgpPeerRemoteAs").
  • $l3->bgp_peer_addr() — reference to hash of BGP peer ➡️ BGP peer IP address ("bgpPeerRemoteAddr").
  • $l3->bgp_peer_fsm_est_trans() — reference to hash of BGP peer ➡️ the total number of times the BGP FSM transitioned into the established state ("bgpPeerFsmEstablishedTransitions").
  • $l3->bgp_peer_in_tot_msgs() — reference to hash of BGP peer ➡️ the total number of messages received from the remote peer on this connection ("bgpPeerInTotalMessages").
  • $l3->bgp_peer_in_upd_el_time() — reference to hash of BGP peer ➡️ the elapsed time in seconds since the last BGP UPDATE message was received from the peer ("bgpPeerInUpdateElapsedTime").
  • $l3->bgp_peer_in_upd() — reference to hash of BGP peer ➡️ the number of BGP UPDATE messages received on this connection ("bgpPeerInUpdates").
  • $l3->bgp_peer_out_tot_msgs() — reference to hash of BGP peer ➡️ the total number of messages transmitted to the remote peer on this connection ("bgpPeerOutTotalMessages").
  • $l3->bgp_peer_out_upd() — reference to hash of BGP peer ➡️ the number of BGP UPDATE messages transmitted on this connection ("bgpPeerOutUpdates").

🗺️ OSPF Interface Table ("ospfIfTable") 🗺️

  • $l3->ospf_if_ip() — reference to hash of OSPF interface IP addresses ("ospfIfIpAddress").
  • $l3->ospf_if_area() — reference to hash of the OSPF area to which the interfaces connect ("ospfIfAreaId").
  • $l3->ospf_if_type() — reference to hash of the OSPF interfaces' type ("ospfIfType").
  • $l3->ospf_if_hello() — reference to hash of the OSPF interfaces' hello interval ("ospfIfHelloInterval").
  • $l3->ospf_if_dead() — reference to hash of the OSPF interfaces' dead interval ("ospfIfRtrDeadInterval").
  • $l3->ospf_if_admin() — reference to hash of the OSPF interfaces' administrative status ("ospfIfAdminStat").
  • $l3->ospf_if_state() — reference to hash of the OSPF interfaces' state ("ospfIfState").

🤝 OSPF Neighbor Table ("ospfNbrTable") 🤝

  • $l3->ospf_peers() — reference to hash of IP addresses the neighbor is using in its IP Source Addresses ("ospfNbrIpAddr").
  • $l3->ospf_peer_id() — reference to hash of neighbor Router IDs ("ospfNbrRtrId").
  • $l3->ospf_peer_state() — reference to hash of state of the relationship with the neighbor routers ("ospfNbrState").

🧵 IS-IS Circuit Table 🧵

  • $l3->isis_circ_if_idx() — reference to hash of the interface index associated with the IS-IS circuit ("isisCircIfIndex").
  • $l3->isis_circ_admin() — reference to hash of the IS-IS circuit's admin status ("isisCircAdminState").
  • $l3->isis_circ_type() — reference to hash of the IS-IS circuit's type ("isisCircType").
  • $l3->isis_circ_level_type() — reference to hash of the IS-IS circuit's level ("isisCircLevelType").

🔗 IS-IS Adjacency Table 🔗

  • $l3->isis_adj_id() — reference to hash of the peer id of adjacencies ("isisISAdjNeighSysID").
  • $l3->isis_adj_type() — reference to hash of the type of adjacencies (Level 1 Intermediate System, Level 2 Intermediate System, Level 1+2 Intermediate System, unknown) ("isisISAdjNeighSysType").
  • $l3->isis_adj_usage() — reference to hash of the type of adjacencies in use (undefined, Level 1, Level 2, Level1+2) ("isisISAdjNeighUsage").
  • $l3->isis_adj_ip_type() — reference to hash of type of address (IPv4, IPv6, etc) on adjacencies ("isisISAdjIPAddrType").
  • $l3->isis_adj() — reference to hash of addresses (IPv4, IPv6, etc) on adjacencies. ⚠️ note: this returns hash-strings, so for IPs, use $l3->isis_peers() instead.
  • $l3->isis_peers() — reference to hash of addresses (IPv4, IPv6) on adjacencies. converts hash strings from isis_adj to proper IP (v4 and v6) formatting. glow-up complete. ✨

📦 Table Methods imported from SNMP::Info 📦

See "USAGE" in SNMP::Info for details.

🌉 Table Methods imported from SNMP::Info::Bridge 🌉

See "TABLE METHODS" in SNMP::Info::Bridge for details.

🔌 Table Methods imported from SNMP::Info::EtherLike 🔌

See "TABLE METHODS" in SNMP::Info::EtherLike for details.

🧩 Table Methods imported from SNMP::Info::Entity 🧩

See "TABLE METHODS" in SNMP::Info::Entity for details.

⚡ Table Methods imported from SNMP::Info::PowerEthernet ⚡

See "TABLE METHODS" in SNMP::Info::PowerEthernet for details.

🌈 Table Methods imported from SNMP::Info::IPv6 🌈

See "TABLE METHODS" in SNMP::Info::IPv6 for details.

📣 Table Methods imported from SNMP::Info::LLDP 📣

See "TABLE METHODS" in SNMP::Info::LLDP for details.

📺 Table Methods imported from SNMP::Info::DocsisHE 📺

See "TABLE METHODS" in SNMP::Info::DocsisHE for details.

☎️ Table Methods imported from SNMP::Info::AdslLine ☎️

See "TABLE METHODS" in SNMP::Info::AdslLine for details.

and that's the whole page bestie!! 🎀 this doc is perl v5.40.1, dated 2026-02-28, and it's straight from the User Contributed Perl Documentation for SNMP::...Layer3(3pm). you absolutely ate that. go forth and poll responsibly. periodt. 💖✨🦋👑

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