I found this line:

FAMT.log: ERROR:ConvertAddrToHostName failed for \\172.15.156.58\DATA

in the famtd.log.

At a glance this looks like a problem in DNS. And could be the truth because there is no Rev.-Ptr. for the IP.

BUT: This is the name(!) of a Netfolder. (This NetFolder was created with FiLR 1.x)

The configured server path for this Netfolder is now \\ncs-12-data\DATA. And the DNS for ncs-12-data is OK. (A-Record and Rev.-Ptr.)

So, why FiLR try to resolve the name(!, not the FQDN!) into a IP?

Maybe someone can have a look into the code to repair this. I assume this can be a root cause for a lot of issues around the netfolders. (but mabe it is only a wrong line in the log ;-)