failsafe

My F5 HA group failed over and although both nodes are in sync the standby node says failsafe. I have 4 defined VLANS and when I run tmsh show sys ha-status 2 of the vlans say yes (in the fail column). in the config utility the 2 vlans that say fail have failsafe enabled and the the other 2 don't have it enabled. I found a thread saying to clear the message, disable failsafe on the vlans on the active and standby nodes. then to reboot the standyby and when it comes back up reneable failsafe. My question is do I want to re enable it, what does it do for me and should it be on all vlans?