One of the FGT fr. HA failed to update AV & IPS db

Hi ALL,

Today, there is a strange issue happened.. suddenly the subnets cannot be accessed which are connected by FGT... it's resumed once reboot the FGT Master (in HA A-A), finally it's found out that there is something wrong with the FGT-A.

After that, when I unplug and plug again the network cables of FGT-A and reboot again, it seems that everything resumed normal even the FGT-A as slave or master.

But now, I found that the FGT-B has an issue - Failed to update AV and IPS database, it seems that the FGT-B cannot access to the FDN... (the AS Filtering shows Unavailable & sometimes the AV also shows unavailable)

Anyone has any idea? Thanks!!

Remark: FGT firmware version: 5.4.4