Performing verification for Focal. I set up a Jammy VM to be the nfs server, using the instructions in the SRU template.
$ sudo cat /proc/fs/nfsd/versions -2 -3 +4 -4.0 +4.1 +4.2 4.0 is not allowed, but 4.1 and 4.2 are. I then started a fresh Focal VM, and installed nfs-common 1.3.4-2.5ubuntu3.5 from -updates. I then tried to mount the NFS share: $ sudo mount -o vers=4 -vvv jammy-nfs-server:/ /mnt mount.nfs: timeout set for Mon Feb 26 01:21:35 2024 mount.nfs: trying text-based options 'vers=4,addr=192.168.122.17,clientaddr=192.168.122.19' mount.nfs: mount(2): Protocol not supported mount.nfs: Protocol not supported as the bug report describes, when we specify -o vers=4 on the mount command line, it only tries 4.0 and no other version. I then enabled -proposed and installed nfs-common 1.3.4-2.5ubuntu3.6. Trying the mount again: $ sudo mount -o vers=4 -vvv jammy-nfs-server:/ /mnt mount.nfs: timeout set for Mon Feb 26 01:27:47 2024 mount.nfs: trying text-based options 'vers=4.2,addr=192.168.122.17,clientaddr=192.168.122.19' $ ll /mnt total 12 drwxr-xr-x 3 root root 4096 Feb 26 01:10 ./ drwxr-xr-x 19 root root 4096 Feb 26 01:13 ../ drwxr-xr-x 2 root root 4096 Feb 26 01:10 users/ This time it correctly tries version 4.2, and since 4.2 is allowed, the mount succeeds. To test the laddering, I went to the nfs-server and then edited /etc/nfs.conf and changed: vers4.2=n and restarted nfs-server.service. Back on the Focal VM, we now see: $ sudo mount -o vers=4 -vvv jammy-nfs-server:/ /mnt mount.nfs: timeout set for Mon Feb 26 01:30:40 2024 mount.nfs: trying text-based options 'vers=4.2,addr=192.168.122.17,clientaddr=192.168.122.19' mount.nfs: mount(2): Protocol not supported mount.nfs: trying text-based options 'vers=4.1,addr=192.168.122.17,clientaddr=192.168.122.19' $ ll /mnt total 12 drwxr-xr-x 3 root root 4096 Feb 26 01:10 ./ drwxr-xr-x 19 root root 4096 Feb 26 01:13 ../ drwxr-xr-x 2 root root 4096 Feb 26 01:10 users/ The laddering works, and we try version 4.2, then 4.1 which succeeds. Lets also turn off 4.1 on the server, and enable 4.0: vers4.0=y vers4.1=n now on the client, we see: $ sudo mount -o vers=4 -vvv jammy-nfs-server:/ /mnt mount.nfs: timeout set for Mon Feb 26 01:32:53 2024 mount.nfs: trying text-based options 'vers=4.2,addr=192.168.122.17,clientaddr=192.168.122.19' mount.nfs: mount(2): Protocol not supported mount.nfs: trying text-based options 'vers=4.1,addr=192.168.122.17,clientaddr=192.168.122.19' mount.nfs: mount(2): Protocol not supported mount.nfs: trying text-based options 'vers=4.0,addr=192.168.122.17,clientaddr=192.168.122.19' $ ll /mnt total 12 drwxr-xr-x 3 root root 4096 Feb 26 01:10 ./ drwxr-xr-x 19 root root 4096 Feb 26 01:13 ../ drwxr-xr-x 2 root root 4096 Feb 26 01:10 users/ We laddered all the way down to 4.0 and connected, since we just allowed it. This works great. The package in -proposed fixes the issue. Happy to mark verified for Focal. ** Tags removed: verification-needed verification-needed-focal ** Tags added: verification-done-focal -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2049262 Title: mount.nfs: fix version negotiation laddering with parameters '-t nfs4' or '-o vers=4' To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nfs-utils/+bug/2049262/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
