NFS UDP was disabled in the upstream kernel[1] in 2019, and the first Ubuntu release with that change was 20.10 (groovy). I didn't find this change in the 20.10 release notes, and added this bit to the 22.04 release notes[2] about a month before the release:
""" UDP disabled for NFS mounts Since Ubuntu 20.10 (“Groovy Gorilla”), the kernel option CONFIG_NFS_DISABLE_UDP_SUPPORT=y is set and this disables using UDP as the transport for NFS mounts, regardless of NFS version. In practice, if you try to use udp, you will get this error: $ sudo mount f1:/storage /mnt -o udp mount.nfs: an incorrect mount option was specified """ If you can't get the older clients to use TCP, then I think the only way is for you to stick to an older Ubuntu release that still has UDP NFS support, like Focal (20.04). 1. https://patchwork.kernel.org/project/linux-nfs/patch/20191121160651.5317-1-olga.kornievsk...@gmail.com/ 2. https://discourse.ubuntu.com/t/jammy-jellyfish-release-notes/24668 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1973101 Title: After upgrade to 22.04 NFS exports for vers 2 and 3 no longer work To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nfs-utils/+bug/1973101/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
