Since upgrading my Ubuntu Machine, all my NFS mounts are hanging. I checked the syslog, and I'm seeing this now:
Sep 29 04:29:10 ip-10-10-10-10 kernel: [ 9589.594814] RPC: AUTH_GSS upcall failed. Please check user daemon is running.
All other methods of debugging NFS still show it up and running (telnet, rpcinfo, etc). What is the AUTH_GSS service and why does it need to be running? I've been running around on Google, but I can't see any reason why it wouldn't already be going.
** UPDATE **
In addition to this, I'm now seeing the following on the server:
Sep 29 05:55:12 ip-10-10-10-10 rpc.gssd: ERROR: can't open /run/rpc_pipefs/gssd/clntXX/info: No such file or directory Sep 29 05:55:12 ip-10-10-10-10 rpc.gssd: ERROR: failed to read service info
** FURTHER DEBUGGING **
To be clear, it's absolutely running, and accepting connections from the client machine. I'm able to telnet over to 111 and 2049 from the client machine with no issue.