XigmaNAS NFS Auth Credentials are too weak

I recently upgraded my NAS4Free server to XigmaNAS. It was a pretty painless affair. I backed up my config using the GUI tool. Installed a fresh copy of XigmaNAS on a flash drive, started it up with the defaults, logged into the GUI and uploaded my config backup. After a reboot I could see it iterating through each of the versions to upgrade the config. Once booted everything seemed to be working without issue.

I then tried to mount the NFS shares from my other systems, but they failed with access denied. It seemed like a good time to enable NFSv4, so I tried that, but made no difference.

When testing from a client and running a tcpdump on the XigmaNAS server I got the following error:

ERR 20: Auth Credentials are too weak

Some google searches didn’t give me much, but did suggest running showmount on the client

showmount -e SERVERIP

This returned no shares. I reviewed all the NFS settings and the exports and it all looked good. rpcbind was running and the firewall was off. I then deleted all the exports thinking maybe there was a problem with the config upgrade. I then mapped /mnt as a test, which showmount happily returned. I then remapped /pool0/share1 but that did not show up in the list. Curious. One comment did suggest checking permissions on the mount points and directories of the target, when I reviewed the folders on the XigmaNAS side I noticed that /pool0 was symlink. I then changed the export to map to the full path, and tadaa, success!