HA failed to Fail over & Logs

[Spartacus1988]

During a planned maintenance our HA setup failed to failover, investigating this further we found that event logs has not been set up. 

1. Are event logs enabled by default ? 

2. For HA failover to take place, how can you tell what triggers it via GUI or CLI ?  (Port going down/ Route tracking) 

3. How do we enable Logs so next time we know what events had taken place?

2 x 3240c in HA : v5.2.10,build742 (GA) 

Any help would be appreicated