I have an Unraid server and a separate media server which Plex runs on. I am running Plex in a container using linuxserver/plex.

I have mounted my Unraid share to my media server through NFS following this guide.

The fstab entry looks like this:

# unraid
192.168.0.30:/mnt/user/unraid /mnt/unraid nfs hard,timeo=50,retrans=5,relatime,rsize=1048576,wsize=1048576 0 0

The Plex service in my docker-compose.yml looks like this:

services:
  plex:
    image: lscr.io/linuxserver/plex:latest
    container_name: plex
    network_mode: host
    environment:
      - PUID=1000
      - PGID=1000
      - TZ=US/Pacific
      - VERSION=docker
    volumes:
      - ./plex/config:/config
      - /mnt/transcode:/transcode
      - /mnt/unraid/Movies:/unraid/movies
      - "/mnt/unraid/Movies 3D:/unraid/movies_3d"
      - /mnt/unraid/Shows:/unraid/shows
      - /mnt/unraid/Sports:/unraid/sports
    ports:
      - 32400:32400
    restart: unless-stopped

Everything starts up fine and all of my shows and movies are recognized when Plex first starts, but after some time (not sure how long), Plex will randomly throw the error in the screenshot:

Please check that the file exists and the necessary drive is mounted.

For some reason, this seems to only happen to Movies. TV shows remain fine. The only way I have been able to resolve it is to restart the Plex service.

I'm at a loss of what can be going on here. Appreciate any advice and suggestions.

My Unraid share settings:

Edited February 6Feb 6 by raphytaffy
Added Unraid share settings

Are the shares set to be cached on the Unraid side? If so this can cause problems when using NFS to access shares when mover runs to transfer files between the 'cache' pool and the main Unraid array.

If you use SMB instead to access such shares then this issue does not occur.

4 minutes ago, itimpi said:

Are the shares set to be cached on the Unraid side? If so this can cause problems when using NFS to access shares when mover runs to transfer files between the 'cache' pool and the main Unraid array.

If you use SMB instead to access such shares then this issue does not occur.

Would the cache settings be set under Shares? I don't see anything there.

I was previously using SMB with no issues, but I read that NFS is better for Ubuntu servers.

5 minutes ago, raphytaffy said:

Would the cache settings be set under Shares? I

If you have secondary storage set for a share then you are 'caching' it.

We can confirm this if you attach your system's diagnostics zip file to your next post in this thread.

It is always a good idea to do this to allow us to see the current state of your system and so we can see logs and configuration information.

12 hours ago, itimpi said:

If you have secondary storage set for a share then you are 'caching' it.

We can confirm this if you attach your system's diagnostics zip file to your next post in this thread.

It is always a good idea to do this to allow us to see the current state of your system and so we can see logs and configuration information.

Thanks. I do have a Cache drive set in Pool Devices, but I do not know if it is set as secondary storage for a share. Where would I find that setting?

Please find my diagnostics attached.

A few questions:

• Is NFS preferred over SMB for Ubuntu servers?

• Can you comment on the recommended mount configuration from this pinned post?

hard,timeo=50,retrans=5,relatime,rsize=1048576,wsize=1048576

Others have suggested:

• Use intr instead to avoid stale hard.

• The timeo is very aggressive.

raphnas-diagnostics-20260206-1207.zip

13 hours ago, itimpi said:

If you have secondary storage set for a share then you are 'caching' it.

If Primary storage is set to Array (as in the screenshot) then it has no secondary storage and is not cached.

Not seeing any obvious issues in the syslog, does it cover a disconnect event?

You may also retry with SMB.

On 2/6/2026 at 1:15 PM, raphytaffy said:

...

A few questions:

• Is NFS preferred over SMB for Ubuntu servers?

It depends on your individual use case and the environment you are using. I've configured, setup and used both countless times in my career. That being said, for my setup, I moved exclusively to SMB/CIFS shares within my network and between all my systems; linux and windows alike. No issues.

See here for more details: https://forums.unraid.net/topic/196474-files-uploaded-via-nfs-mount-have-wrong-user-and-permissions-drwxr-xr-x-for-directories-and-rw-r-r-for-files/#comment-1601671

Edited February 8Feb 8 by TrevP

On 2/8/2026 at 7:28 AM, TrevP said:

It depends on your individual use case and the environment you are using. I've configured, setup and used both countless times in my career. That being said, for my setup, I moved exclusively to SMB/CIFS shares within my network and between all my systems; linux and windows alike. No issues.

See here for more details: https://forums.unraid.net/topic/196474-files-uploaded-via-nfs-mount-have-wrong-user-and-permissions-drwxr-xr-x-for-directories-and-rw-r-r-for-files/#comment-1601671

Thank you so much for this.

I was actually using SMB before my OS crashed and I had to set up my media server again, which is when I started doing research and saw that most people tend to use NFS with Ubuntu Server. It's strange that I'm hitting these issues though, so I think I will move back to SMB.

I really appreciate the post that you linked. I think that will help with setting the right mount options.

I'm actually trying to use the CIFS settings from the thread that you linked, but I can't seem to get it to mount.

Here is my /etc/fstab entry:

192.168.0.30:/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

And when I try to run mount -t cifs manually, I get this error:

> sudo mount -t cifs -o 192.168.0.30:/mnt/user/unraid /mnt/unraid
mount: /mnt/unraid: bad option; for several filesystems (e.g. nfs, cifs) you might need a /sbin/mount.<type> helper program.
       dmesg(1) may have more information after failed mount system call.

Edited February 13Feb 13 by raphytaffy

That mount command doesn't look right, but first check if cifs-utils is installed:

which mount.cifs

42 minutes ago, JorgeB said:

That mount command doesn't look right, but first check if cifs-utils is installed:

which mount.cifs

I had to install it first:

> sudo apt install cifs-utils
> which mount.cifs
/usr/sbin/mount.cifs

The /etc/fstab entry still doesn't work though:

192.168.0.30:/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

Try this:

//192.168.0.30/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

6 hours ago, raphytaffy said:

I had to install it first:

> sudo apt install cifs-utils
> which mount.cifs
/usr/sbin/mount.cifs

The /etc/fstab entry still doesn't work though:

192.168.0.30:/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

As @JorgeB showed. You are missing the leading "//" in the fstab entry.

19 hours ago, JorgeB said:

Try this:

//192.168.0.30/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

Hmm I'm still having trouble getting this to work:

//192.168.0.30/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

I have set SMB Security Settings > Security > Public. Do I have to set any particular mount setting for fstab to pick up the mount?

Edited February 14Feb 14 by raphytaffy

Do you see any error logged when it tries to connect?

15 hours ago, JorgeB said:

Do you see any error logged when it tries to connect?

I tried mount -a and it shows this error message:

> sudo mount -a
mount error(2): No such file or directory
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs) and kernel log messages (dmesg)

I am trying to manually connect first before debugging the fstab entry:

> sudo mount -t cifs //192.168.0.30/mnt/user/unraid /mnt/unraid
Password for root@//192.168.0.30/mnt/user/unraid: my_unraid_password
mount error(2): No such file or directory
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs) and kernel log messages (dmesg)

Error:

> sudo dmesg
[65793.339682] CIFS: Attempting to mount //192.168.0.30/mnt/user/unraid
[65793.345092] CIFS: VFS: \\192.168.0.30 failed to connect to IPC (rc=-13)
[65793.345104] CIFS: VFS: session 000000005e5fce55 has no tcon available for a dfs referral request
[65793.346166] CIFS: VFS: cifs_mount failed w/return code = -2

9 hours ago, raphytaffy said:

Password for root

First, you cannot use root, root cannot access SMB shares, you must create a user and add permissions for the share, or set the share to public

Second, you must use the share path (//sever_name/share_nome), not the local one, e.g:

sudo mount -t cifs //192.168.0.30/unraid /mnt/unraid

use

//192.168.0.30/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino 0 0

not

//192.168.0.30/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

Note the two changes. You want to mount the "Share", not the path; and I no longer disable caching by default. The standard "cache=strict" is used by default and good enough for the vast majority of uses.

Thank you so much! This did the trick!

On 2/20/2026 at 11:13 AM, TrevP said:

use

//192.168.0.30/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino 0 0

not

//192.168.0.30/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

Note the two changes. You want to mount the "Share", not the path; and I no longer disable caching by default. The standard "cache=strict" is used by default and good enough for the vast majority of uses.

On 2/20/2026 at 11:13 AM, TrevP said:

use

//192.168.0.30/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino 0 0

not

//192.168.0.30/mnt/user/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,cache=none 0 0

Note the two changes. You want to mount the "Share", not the path; and I no longer disable caching by default. The standard "cache=strict" is used by default and good enough for the vast majority of uses.

So the mount is mounted properly, but I can't seem to write to it:

> cp test_file /mnt/unraid
cp: cannot create regular file '/mnt/unraid/test_file': Permission denied

Edit: fixed by adding my uid:

//192.168.0.30/unraid /mnt/unraid cifs rw,guest,_netdev,noatime,noserverino,uid=1000,gid=1000,file_mode=0777,dir_mode=0777 0 0

Edited February 27Feb 27 by raphytaffy