check_route_nexthop.sh

Sometimes we have dynamic routing protocols and we don´t know which route is active at a certain time.
This plugin checks via snmp a route associated with a gateway (next hop), if either the route is down or the gateway changes a warning alarm is triggered.


Usage:

check_route_nexthop.sh [host address] [snmp v2c community] [network] [netmask] [gateway]


Example:

./check_route_nexthop.sh 192.168.10.1 public 192.168.50.0 255.255.255.0 172.17.33.13

Notes:
Network, netmask and gateway need to be exactly as seen in device routing table (show ip route on ios).
Tested on Cisco IOS and Juniper Screenos. It uses standard RFC MIBS, so it should work on every decent network device.
Tested on Nagios Core 3.2.3, I hope it works on the rest of the versions.

TODO:
1. Command swithes (including help)
2. Snmp options (including support for snmpv3)
3. Detailed documentation

Please feel free to finish this plugin, I´m a bit lazy :P