I have two 1900 series routers in production for the last two years.
The routers have 2 interfaces LAN & WAN. HSRP is enabled on LAN interface with link monitoring for WAN interface. Routers were tested for failover before putting into production and worked fine.
Today suddenly the active HSRP router got hung and I could not connect to it remotely. Surprisingly the standby router did not become active. Since this was at the remote location, I asked the remote staff to shutdown the faulty router . Then HSRP switchover took place. After 10 minutes the faulty router was powered on and became active again.
I have no logs on syslog server to identify the issue. How can I pinpoint this issue? It seems like when the router got hung it did not give up its HSRP priority.