Interpreting fail over log

Can someone help me interpret the below log that appears in tail /var/log/ltm

 

June 9 13:23 slot1/Guest 2 notice sod[9009] 010c0045: Command: go standby tmsh

 

Did the switchover happen as a result to a command or did some failsafe mechanism trigger it. Please be informed we have gateway failsafe configured on the LTM HA pair