1f1ba32c1b26b0c3bb491aeace707932f94280c6
NAME
SNMP::Info - Perl5 Interface to Network devices through SNMP.
VERSION
SNMP::Info - Version 0.3
AUTHOR
Max Baker ("max@warped.org")
SNMP::Info was created for the Netdisco application at UCSC
COPYRIGHT AND LICENCE
Copyright (c) 2002-3, 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.
SYNOPSIS
# Connect with generic Info object
my $info = new SNMP::Info( DestHost => 'router' ,
Community => 'public' );
$name = $info->name();
# Try and find a more specific subclass of SNMP::Info
my $object_class = $info->device_type();
my $more_specific_device = new $object_class(
'Desthost' => 'mydevice',
'Community' => 'public');
# Find out the Duplex status for the ports
my $interfaces = $more_specific_device->interfaces();
my $i_duplex = $more_specific_device->i_duplex();
# Get CDP Neighbor info
my $c_ip = $more_specific_device->c_ip();
my $c_port = $more_specific_device->c_port();
foreach my $iid (keys %$interfaces){
my $duplex = $i_duplex->{$iid};
# Print out physical port name, not snmp iid
my $port = $interfaces->{$iid};
my $neighbor_ip = $c_ip->{$iid};
my $neighbor_port = $c_port->{$iid};
print "$port: Duplex $duplex\n";
print " Neighbor : $neighbor_ip \@ $neighbor_port\n";
}
REQUIREMENTS
1. Net-SNMP
To use this module, you must have Net-SNMP installed on your system.
Net-SNMP can be found at http://net-snmp.sourceforge.net . Version
5.0.2 or greater is recommended.
The Perl module "SNMP" is found inside the distribution. Go to the
perl/ directory and install it from there, or run "./configure
--with-perl-modules" .
2. MIBS
Each sub-module that you use will also require specific MIBs,
usually obtainable on the net. See the list above for a quick
glance, and the documentation in each sub module for more
information.
Make sure that your snmp.conf is updated to point to your MIB
directory and that the MIBs are world-readable.
SNMP::Info requires RFC1213-MIB (and whatever supporting MIBs that
are referenced).
A good starting point are the Version 2 MIBs from Cisco, found at
ftp://ftp.cisco.com/pub/mibs/v2/v2.tar.gz
Run "cd /usr/local/share/snmp/mibs && tar xvfz ~/v2.tar.gz " to
install them.
Then run "snmpconf" and setup that directory as default. Move
snmp.conf into /usr/local/share/snmp when you are done.
DESCRIPTION
SNMP::Info gives an object oriented interface to information obtained
through SNMP.
This module is geared towards network devices. Speciality sub-classes
exist for a number of vendors and products (see below).
Design Goals
1. Use of MIB variables and values instead of purely numeric OID
All values are retrieved via MIB Leaf node names.
This means that SNMP::Info only asks SNMP::Session to look for
``sysName'' instead of 1.3.6.1.2.1.1.5.
It also means that you need to download MIB files for each sub
module that you use.
The other side effect to using MIBs is data results come back as
meaningful text, instead of integers.
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 sub class for a device by filling in Four
hashes %GLOBALS, %MIBS, %FUNCS, and %MUNGE with the names of the
SNMP attributes that are specific to your device. See the bottom of
this document for a sample Sub Class.
When you make a new sub class for a device, please be sure to send
it back to the developers at snmp@warped.org for inclusion in the
next version.
Sub Classes
SNMP::Info::Bridge
SNMP::Info::CDP
SNMP::Info::EtherLike
SNMP::Info::MAU
SNMP::Info::Layer1
SNMP::Info::Layer2
SNMP::Info::Layer3
SNMP::Info::Layer1::Allied
SNMP::Info::Layer1::Asante
SNMP::Info::Layer2::Bay
SNMP::Info::Layer2::C1900
SNMP::Info::Layer2::C2900
SNMP::Info::Layer2::Catalyst
SNMP::Info::Layer2::HP
SNMP::Info::Layer3::Aironet
SNMP::Info::Layer3::Foundry
SNMP::Info::Layer3::C3550
Details
* SNMP::Info::Bridge - BRIDGE-MIB - RFC1286 Support
Requires BRIDGE-MIB
* SNMP::Info::CDP - Cisco Discovery Protocol (CDP) Support.
Provides Layer 2 Topology Information on Cisco and some HP Devices.
Requires CISCO-CDP-MIB
* SNMP::Info::EtherLike
Requires ETHERLIKE-MIB - RFC1398
* SNMP::Info::Layer1 - Generic Layer 1 Device Support
Requires Standard V1 and V2 MIBs
* SNMP::Info::Layer2 - Generic Layer 2 Device Support
Inherits:
SNMP::Info::CDP
SNMP::Info::Bridge
Required MIBs:
CISCO-PRODUCTS-MIB - Gives model information for Cisco
HP-ICF-OID - Gives model information for HPs
* SNMP::Info::Layer3 - Generic Layer 3 and Layer 2/3 Device Support
Inherits:
SNMP::Info::Bridge - For Layer 2/3 devices
SNMP::Info::CDP
SNMP::Info::EtherLike
Required MIBs:
CISCO-PRODUCTS-MIB - Gives model information for Cisco
HP-ICF-OID - Gives model information for HPs
ENTITY-MIB - Gives some chassis information
OSPF-MIB - Gives router information
* SNMP::Info::MAU - RFC2668 - Media Access Unit (MAU) MAU-MIB
* SNMP::Info::Layer1::Allied - Allied TeleSys Hub Support
Requires ATI-MIB - Allied Devices MIB downloadable from
http://www.allied-telesyn.com/allied/support/
* SNMP::Info::Layer1::Asante - Asante 1012 Hubs
Requires ASANTE-HUB1012-MIB - Download from http://www.mibdepot.com
* SNMP::Info::Layer2::Bay - Bay Networks BayStack Switch Support
Required MIBs:
SYNOPTICS-ROOT-MIB - Gives model information for Bay
S5-ETH-MULTISEG-TOPOLOGY-MIB - Gives Layer 2 topology information for Bay
Other supporting MIBs needed, see SNMP::Info::Bay for more info
* SNMP::Info::Layer2::C1900 - Cisco 1900 and 1900c Device Support
Requires STAND-ALONE-ETHERNET-SWITCH-MIB (ESSWITCH-MIB)
* SNMP::Info::Layer2::C2900 - Cisco 2900 Series Device Support.
Requires CISCO-C2900-MIB
* SNMP::Info::Layer2::Catalyst - Cisco Catalyst WSC Series Switch
Support
Requires MIBs:
CISCO-STACK-MIB
CISCO-VTP-MIB
* SNMP::Info::Layer2::HP - HP Procurve Switch Support
Inherits:
SNMP::Info::MAU
Required MIBs:
ENTITY-MIB
RFC1271-MIB
HP-ICF-OID
* SNMP::Info::Layer3::Aironet - Cisco Aironet Wireless Access Points
(AP) Support
Required MIBs:
AWCVX-MIB - Aironet Specific MIB values
IEEE802dot11-MIB - IEEE 802.11 Specific MIB (currently draft)
* SNMP::Info::Layer3::C3550 - Cisco Catalyst 3550 Layer2/3 Switch
* SNMP::Info::Layer3::Foundry - Older Foundry Networks Devices Support
Inherits SNMP::Info::Bridge
Requires FOUNDRY-SN-ROOT-MIB - Foundry specific values. See
SNMP::Info::Layer3::Foundry for more information.
METHODS
These are generic methods from RFC1213. Some subset of these is
probably available for any network device that speaks SNMP.
Constructor
new()
Creates a new object and connects via SNMP::Session.
Arguments given are passed to SNMP::Session and can be used to
overide defaults.
Data is Cached
A call to any of these methods will load the data once, and then return
cached versions of that data.
Use load_METHOD() to reload from the device
$data = $cdp->c_ip();
...
$cdp->load_c_ip();
$newdata = $cdp->c_ip();
Scalar Methods
$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 for.
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.
Algorithm for SubClass Detection:
Layer3 Support -> SNMP::Info::Layer3
Aironet -> SNMP::Info::Layer3::Aironet
Catalyst 3550 -> SNMP::Info::Layer3::C3550
Foundry -> SNMP::Info::Layer3::Foundry
Elsif Layer2 (no Layer3) -> SNMP::Info::Layer2
Bay Networks -> SNMP::Info::Layer2::Bay
Catalyst 1900 -> SNMP::Info::Layer2::C1900
Catalyst 2900XL (IOS) -> SNMP::Info::Layer2::C2900
Catalyst WS-C (2926,5xxx,6xxx) -> SNMP::Info::Layer2::Catalyst
HP Procurve -> SNMP::Info::Layer2::HP
Elsif Layer1 Support -> SNMP::Info::Layer1
Allied -> SNMP::Info::Layer1::Allied
Asante -> SNMP::Info::Layer1::Asante
Else -> SNMP::Info
$info->has_layer(3)
Returns non-zero if the device has the supplied layer in the OSI
Model
Returns "undef" if the device doesn't support the layers() call.
$info->uptime()
Uptime in hundreths 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.
(sysServices)
$info->ports()
Number of interfaces available on this device.
(ifNumber)
Table Methods
Each of these methods returns a hash_reference to a hash keyed on the
interface index in SNMP.
Example : $cdp->c_ip() returns
{ '304' => '123.123.231.12' }
Interfaces
$info->interfaces()
This methods is overriden 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.
SNMP::Info and it's subclasses tries to provide data on Physical
ports.
$info->i_index()
Defaults to $info->interfaces()
(ifIndex)
$info->i_description()
Returns reference to hash keyed by iid. Values are the Textual
Description of the interface (port). Usually the physical /
human-friendly name.
(ifDescr)
$info->i_type()
Returns reference to hash keyed by iid. Values are the port type,
such as Vlan, 10baseT, Ethernet, Serial...
(ifType)
$info->i_mtu()
Returns reference to hash keyed by iid. Values are the MTU value for
the port.
(ifMtu)
$info->i_speed()
Returns reference to hash keyed by iid. Values are the speed of the
link.
(ifSpeed)
$info->i_mac()
Returns reference to hash keyed by iid. Values are the MAC address
of the interface. Note this is just the MAC of the port, not
anything connected to it.
(ifPhysAddress)
$info->i_up()
Returns reference to hash keyed by iid. Values are the Link Status
of the interface. Typical values are 'up' and 'down'.
(ifOperStatus)
$info->i_up_admin()
Returns reference to hash keyed by iid. Values are the
administrative status of the port. Typical values are 'enabled' and
'disabled'.
(ifAdminStatus)
$info->i_name()
Returns reference to hash keyed by iid. Values are the Interface
Name field. Supported by a smaller subset of devices, this fields is
often human set.
(ifName)
$info->i_alias()
Returns reference to hash keyed by iid. Values are a differnent
version of the Interface Description or Interface Name. 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)
IP Address Table
Each entry in this table is an IP address in use on this device. Usually
this is implemented in Layer3 Devices.
$info->ip_index()
Maps the IP Table to the IID
(ipAdEntIfIndex)
$info->ip_table()
Maps the Table to the IP address
(ipAdEntAddr)
$info->ip_netmask()
Gives netmask setting for IP table entry.
(ipAdEntNetMask)
$info->ip_broadcast()
Gives broadcast address for IP table entry.
(ipAdEntBcastAddr)
Default %MUNGE
ip -> &munge_ip
mac -> &munge_mac
i_mac -> &munge_mac
layers -> &munge_dec2bin
CREATING SUBCLASSES
Data Structures Used in SNMP::Info and SubClasses
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 iid name ) These
are scalar values such as name,uptime, etc.
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 iid) These are
table entries, such as the IfIndex
%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 sub routine
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 Sub Class
Let's make a sample Layer 2 Device subclass :
# SNMP::Info::Layer2::Sample
package SNMP::Info::Layer2::Sample;
$VERSION = 0.1;
use strict;
use Exporter;
use SNMP::Info::Layer2;
@SNMP::Info::Layer2::Sample::ISA = qw/SNMP::Info::Layer2 Exporter/;
@SNMP::Info::Layer2::Sample::EXPORT_OK = qw//;
use vars qw/$VERSION %FUNCS %GLOBALS %MIBS %MUNGE $AUTOLOAD $INIT $DEBUG/;
%MIBS = (%SNMP::Info::Layer2::MIBS,
'SUPER-DOOPER-MIB' => 'supermibobject'
);
%GLOBALS = (%SNMP::Info::Layer2::GLOBALS,
'name' => 'supermib_supername',
'favorite_color' => 'supermib_fav_color_object',
'favorite_movie' => 'supermib_fav_movie_val'
);
%FUNCS = (%SNMP::Info::Layer2::FUNCS,
# Super Dooper MIB - Super Hero Table
'super_hero_index' => 'SuperHeroIfIndex',
'super_hero_name' => 'SuperHeroIfName',
'super_hero_powers' => 'SuperHeroIfPowers'
);
%MUNGE = (%SNMP::Info::Layer2::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;
}
# Add Copious Documentation here!!!
Be sure and send the debugged version to snmp@warped.org to be included
in the next version of SNMP::Info.
Data Munging Callback Subs
munge_speed()
Makes human friendly speed ratings using %SPEED_MAP
%SPEED_MAP = (
'64000' => '64 kbps',
'1500000' => '1.5 Mbps',
'1544000' => 'T1',
'2000000' => '2.0 Mbps',
'2048000' => '2.048 Mbps',
'4000000' => '4.0 Mbps',
'10000000' => '10 Mbps',
'11000000' => '11 Mbps',
'20000000' => '20 Mbps',
'16000000' => '16 Mbps',
'45000000' => 'DS3',
'45045000' => 'DS3',
'64000000' => '64 Mbps',
'100000000' => '100 Mbps',
'149760000' => 'OC-1'
'155000000' => 'OC-1'
'400000000' => '400 Mbps',
'622000000' => 'OC-12',
'599040000' => 'OC-12',
'1000000000' => '1.0 Gbps',
);
munge_ip()
Takes a binary IP and makes it dotted ASCII
munge_mac()
Takes an 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
Internaly Used Functions
$info->init()
Used internally. Loads all entries in %MIBS.
$info->debug(1)
Turns on debugging info for this class and SNMP
$info->class()
Returns the class name of the object.
$info->funcs()
Returns a reference to the %FUNCS hash.
$info->mibs()
Returns a reference to the %MIBS hash.
$info->globals()
Returns a reference to the %GLOBALS hash.
$info->munge()
Returns a reference ot the %MUNGE hash.
$info->session()
Gets or Sets the SNMP::Session object.
Functions for SNMP Scalars (%GLOBALS)
$info->_global()
Used internally by AUTOLOAD to load dynmaic methods from %GLOBALS.
Example: $info->name() calls autoload which calls
$info->_global('name').
$info->_set(attr,val,iid)
Used internally by AUTOLOAD to run an SNMP set command for dynamic
methods listed in either %GLOBALS or %FUNCS.
Example: $info->set_name('dog',3) uses autoload to resolve to
$info->_set('name','dog',3);
Functions for SNMP Tables (%FUNCS)
$info->load_all()
Runs $info->load_METHOD() for each entry in %FUNCS.
Returns { iid => values_hash } where value_hash is in the format: {
attribute => value }
$info->all()
Runs $info->load_all() once then returns the cached data.
Use $info->load_all() to reload the data.
$info->_load_attr()
Used internally by AUTOLOAD to fetch data called from methods listed
in %FUNCS.
Called from $info->load_METHOD();
$info->_show_attr()
Used internaly by AUTOLOAD to return data called by methods listed
in %FUNCS.
Called like $info->METHOD().
The first time ran, it will call $info->load_METHOD(). Every time
after it will return cached data.
AUTOLOAD
Each entry in either %FUNCS or %GLOBALS is used by AUTOLOAD() to create
dynamic methods.
First Autoload sees if the method name is listed in either of the two
hashes.
If the method exists in globals, it runs $info->_global(method).
Next it will check %FUNCS, run $info->_load_attr(method) if needed and
return $info->_show_attr(method).
Override any dynamic method listed in one of these hashes by creating a
sub with the same name.
Example : Override $info->name() by creating `` sub name {}'' in your
Module.
Description
Languages
Perl
79.8%
Raku
20.2%