Ubuntu server v24.04.3 LTS (GNU/Linux 6.8.0-88-generic x86_64) (VM running on Proxmox v6.8.12-11-PVE)
Proxmox host ((for backups, iso, more) is also experiencing the same NFS disconnections).
I have been dealing with NFS shares working, then disconnecting periodically (I am seeing no pattern as of now), but will sometimes resume without completely rebooting a client or the share itself. NFS-common is installed on the client, too. SMB & iSCSI have been working fine without issues. Sometimes it will restore without intervention (can take 5 minutes to hours), require a reboot on the client (a hard reset in my case because the system locks up because of qBittorrent not done sending data), disabling and reenabling NFS on TrueNAS, or in extreme cases, a reboot for the client and TrueNAS.
What I have done:
Reinstalled TrueNAS & Ubuntu (client) & restored my config
Used different clients (including a fresh Ubuntu install)
Tried using NFSv3
Rebooted everything (router and all)
Monitored network ping from client to TrueNAS server (no issues)
Update everything
That Ubuntu client only has Podman, Portainer, Gluetun, qBittorrent, & any required things for those to run.
Mount settings on the Ubuntu client: 10.10.0.156:/mnt/<truenas mount point> /home/administrator/<mount point> nfs rw,hard 0 0
I have attached dmesg logs from the client and TrueNAS kernel logs. I also want to note, if I use SMB/CIFS on the same client, I will have issues with it on Ubuntu server v24.04.3 LTS, but I have no issues on my Windows client (bare metal) with SMB.
After a month of troubleshooting, I finally found the issue, which is still bizarre to me, and I haven’t talked to Ubiquiti for reasons why it wasn’t working. On my quest to upgrade my networking to multigig speeds and install a switch, I noticed that once I moved my storage traffic off the UDM Pro, the problem went away. What is weird is that SMB shares would work on my main Windows PC, but not on my torrenting VM (after more troubleshooting). No matter the protocol (SMB or NFS), the connection would drop after some time, restore, & repeat.
I suspect that it is the UDM Pro blocking the connection or something else. It makes it more weird that it was only the share going down, and that VM, along with the other VMs on that Proxmox host, would not lose an internet connection. The shares on the other VMs and hosts were all working too.
Since offloading that traffic to a switch, I have not seen a single disconnect, even with that switch’s uplink connected to the same UDM Pro. Leaving off or offloading the routing to the switch itself (it is a L3 one) did not change the results.
That switch has been installed for over a week, and so far, I have not had any issues with TrueNAS, that torrenting VM, or any of my shares disconnecting, regardless of the protocol being used.
The 8 port switch on the UDM Pro has some limits. It is only line rate between the 8 ports itself. So if you have traffic between port 1 and port 2, no issued. However if you need to leave those ports for the WAN or the SFP+ LAN you can have issues. The switch chip is really 9 ports. The 9th port is wired to the CPU. All traffic that goes to the WAN or other LAN side passes thought the CPU and the firewall rules, state time outs, etc. The 8 port should never be used for something that really matters. I use mine for IPMI and OOB management connections.
