SNMP::Info::CDP - Perl5 Interface to Cisco Discovery Protocol (CDP) using SNMP
Max Baker
my $cdp = new SNMP::Info ( AutoSpecify => 1, Debug => 1, DestHost => 'router', Community => 'public', Version => 2 ); my $class = $cdp->class(); print " Using device sub class : $class\n"; $hascdp = $cdp->hasCDP() ? 'yes' : 'no'; # Print out a map of device ports with CDP neighbors: my $interfaces = $cdp->interfaces(); my $c_if = $cdp->c_if(); my $c_ip = $cdp->c_ip(); my $c_port = $cdp->c_port(); foreach my $cdp_key (keys %$c_ip){ my $iid = $c_if->{$cdp_key}; my $port = $interfaces->{$iid}; my $neighbor = $c_ip->{$cdp_key}; my $neighbor_port = $c_port->{$cdp_key}; print "Port : $port connected to $neighbor / $neighbor_port\n"; }
SNMP::Info::CDP is a subclass of SNMP::Info that provides an object oriented interface to CDP information through SNMP.
CDP is a Layer 2 protocol that supplies topology information of devices that also speak CDP, mostly switches and routers. CDP is implemented in Cisco and some HP devices.
Create or use a device subclass that inherits this class. Do not use directly.
Each device implements a subset of the global and cache entries. Check the return value to see if that data is held by the device.
None.
MIBs can be found at ftp://ftp.cisco.com/pub/mibs/v2/v2.tar.gz
These are methods that return scalar values from SNMP
Is CDP is active in this device?
Accounts for SNMP version 1 devices which may have CDP but not cdp_run()
Is CDP enabled on this device? Note that a lot of Cisco devices that implement CDP don't implement this value. @#%$!
(cdpGlobalRun)
Interval in seconds at which CDP messages are generated.
(cdpGlobalMessageInterval)
Time in seconds that CDP messages are kept.
(cdpGlobalHoldTime)
Returns CDP device ID.
This is the device id broadcast via CDP to other devices, and is what is retrieved from remote devices with $cdp->id().
(cdpGlobalDeviceId)
These are methods that return tables of information in the form of a reference to a hash.
Returns Device Functional Capabilities. Results are munged into an ascii binary string, 7 digits long, MSB. Each digit represents a bit from the table below.
From http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm#18843:
(Bit) - Description
Thanks to Martin Lorensen martin -at- lorensen.dk for a pointer to this information.
martin -at- lorensen.dk
(cdpCacheCapabilities)
Returns remote VTP Management Domain as defined in CISCO-VTP-MIB::managementDomainName
(cdpCacheVTPMgmtDomain)
Returns the port duplex status from remote devices.
(cdpCacheDuplex)
Returns remote device id string
(cdpCacheDeviceId)
Returns the mapping to the SNMP Interface Table.
Note that a lot devices don't implement $cdp->c_index(), So if it isn't around, we fake it.
In order to map the cdp table entry back to the interfaces() entry, we truncate the last number off of it :
# it exists, yay. my $c_index = $device->c_index(); return $c_index if defined $c_index; # if not, let's fake it my $c_ip = $device->c_ip(); my %c_if foreach my $key (keys %$c_ip){ $iid = $key; ## Truncate off .1 from cdp response $iid =~ s/\.\d+$//; $c_if{$key} = $iid; } return \%c_if;
Returns the mapping to the SNMP2 Interface table for CDP Cache Entries.
Most devices don't implement this, so you probably want to use $cdp->c_if() instead.
See c_if() entry.
(cdpCacheIfIndex)
Returns remote IP address
(cdpCacheAddress)
Returns remote platform id
(cdpCachePlatform)
Returns remote port ID
(cdpDevicePort)
Returns remote address type received. Usually IP.
(cdpCacheAddressType)
Returns remote hardware version
(cdpCacheVersion)
Returns the remote interface native VLAN.
(cdpCacheNativeVLAN)
To install SNMP::Info, copy and paste the appropriate command in to your terminal.
cpanm
cpanm SNMP::Info
CPAN shell
perl -MCPAN -e shell install SNMP::Info
For more information on module installation, please visit the detailed CPAN module installation guide.