Cisco Routers: HSRP Group Status
Cisco routers support virtual redundant interfaces by using HSRP
(Hot Standby Router Protocol).
HSRP is configured by assigning IP interfaces to a group that has a
"floating" virtual IP.
If, for example, a router has an interface failure on either of the routed
interfaces, the protocol lowers the routers priority, and if that priority
drops too low, it will fail over the virtual IP.
The check returns
OK if the HSRP status is a good one ("active",
"standby") and the same as during inventory.
If the states flip from "active" to "standby" or vice-versa, the check goes
WARN, assuming that HSRP is doing it's job.
Should the status ever be a different one that for example points to HSRP
still initializing, the check will return
CRIT as HSRP is assumed to be
inoperable in these states.
The Virtual IP of the failover group.
One service is created per virtual IP.
The check reads the HSRP MIB.
If the HSRP state of the group is either active or standby, a service
will be created. It also stores this HSRP state of
the IP as seen by the monitored device.
It also stores the ID of the failover group. (For future use)