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Synology NFS 'access denied' and resolution

Fun time figuring this out, I was being bad and not documenting, but here's what I recall:

  • Kept getting 'access denied by server while mounting' errors when using this command: mount -t nfs /srv/backup
  • Checked and re-checked the Synology settings to no avail.  Thought it was something to do with root squash - was not.
  • Correct settings should be correct IP address, RW, No Mapping, Enable Async
  • SSH'd in to the Synology and after some messing about with /etc/exports, I set up tail -f /var/log/messages
  • Took me a while to notice it, but the IP it was registering was the Astaro gateway IP - the Synology and my PC are on different subnets!
  • Set the NFS rule to '*' and started working immediately.
  • Firewalls make it easy to overlook simple things.  I imagine there is some sort of fancy NAT rule for the NFS traffic that would allow specific IPs, but seeing as how I'm technically behind two firewalls and this is a lab, the allow all rule will work for the time being.

If I were setting up a production environment and/or not using a NAS for my backups, I'd not leave such a wide security issue open.  The issue is noted here, and maybe I'll fix it at some point, just to find out what's involved in getting it to work.

Fun Synology stuff:
  • /usr/syno/etc/rc.d/ restart/stop/start
  • cat /etc/exports



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