The Bourne Shell script in Example 1-3 uses SNMP to extract useful version information from a list of routers. By default, the script will store this data in CSV format so you can easily import it into a spreadsheet for analysis. No arguments are required or expected.
Example 1-3. inventory.sh
#!/bin/sh # # inventory.sh -- a script to extract valuable information # from a list of routers. (Name, Type, IOS version) # # # Set behaviour public="ORARO" workingdir="/home/cisco" # LOG=$workingdir/RESULT.csv infile=$workingdir/RTR_LIST snmp="/usr/local/bin/snmpget -v1 -c $public" # while read device do $snmp $device sysName.0 > /dev/null if [ "$?" = "0" ] ; then rtr=\Q$snmp $device .220.127.116.11.18.104.22.168.1.3.0 | cut -f2 -d\" \Q type2=\Q$snmp $device .22.214.171.124.126.96.36.199.188.8.131.52.2.3 | cut -f2 -d$ \Q ios=\Q$snmp $device .184.108.40.206.220.127.116.11.18.104.22.168.2.5 | cut -f2 -d$ \Q prot=\Q$snmp $device .22.214.171.124.126.96.36.199.188.8.131.52.2.4 | cut -f2 -d$ \Q echo "$device, $rtr, $type2, $ios, $prot" >> $LOG fi done < $infile
The inventory.sh script extracts hardware and IOS version information directly from the routers using SNMP. This ensures that the data is up to date. You can even automate this script so it runs periodically to make sure that your inventory information is always accurate. In a large network, this is much easier than keeping track of this information manually.
By default, the script captures the device name, router type,
IOS version, and IOS feature set from each router. It stores this
information gathered in a CSV format file called
This script requires NET-SNMP to gather the information via
SNMP. You could use a different SNMP package if you prefer, but then
you will need to modify the syntax appropriately. The script expects
to find the executable snmpget in
usr/local/bin. Again, if you keep this file
in a different location, you will need to define the correct location
in the variable
snmp. For more
information on NET-SNMP, see Chapter 17 or Appendix A.
Before running this script in your network, you will need to
modify two variables. The first is the variable called
public. This value must contain your
read-only SNMP community string.
The script assumes that you have the same community string on all of
the routers in the list. The second variable that you will need to set
workingdir, which must contain
the name of the directory that you wish to run the script from.
Finally, you will need to build a file called
RTR_LIST that contains the names of all of
your routers, with one name on each line. The script expects to find
this file in the working directory.
The output of the script is a CSV file, which you can import into a spreadsheet to analyze and sort the results as required. Table 1-4 shows an example of the script’s output as it might look in a spreadsheet.
Table 1-4. Output results from the inventory.sh script
|Router||Router name||Type||IOS version||IOS feature set|
|Toronto||toronto||C2500||12.2(1d)||ENTERPRISE|FIREWALL PLUS IPSEC 56|