** Description changed: + [ Impact ] + + NFSv4-only shares cannot be automounted if the server isn't running (or + is blocking) rpcbind, even though NFSv4 doesn't require rpcbind anymore. + + [ Test Plan ] + + You will two Jammy VMs (unfortunately lxd VMs won't work, so you will + likely need to use qemu/libvirt). One will act as the NFSv4-only + server, and the other will be the client with autofs configured. + + Here are the steps to configure the server VM: + + Install the NFS server: + + # apt install -y nfs-kernel-server + + Then, edit the nfs-server.service file: + + # systemctl edit --full nfs-server.service + + Remove any mentions to rpcbind.socket from the [Unit] section. Also, + edit the ExecStart line to look like: + + ExecStart=/usr/sbin/rpc.nfsd --no-nfs-version 3 + + Stop and mask the rpcbind.* systemd units: + + # systemctl stop rpcbind.socket rpcbind.service + # systemctl mask rpcbind.socket rpcbind.service + + Create a directory to share and export it: + + # mkdir /testshare + # touch /testshare/testfile + # echo -e '/testshare\t*(rw,sync,no_subtree_check)' >> /etc/exports + + Restart nfs-server: + + # systemctl restart nfs-server.service + + + Here are the steps to configure the client VM: + + Install nfs-common and autofs: + + # apt install -y nfs-common autofs + + Add the automount configuration for the share (replace NFS_SERVER_IP + with the IP address of the server VM you've just configured above): + + # echo -e '/mnt\t/etc/auto.nfs' >> /etc/auto.master + # echo -e 'test\t-fstype=nfsv4\tNFS_SERVER_IP:/testshare' >> /etc/auto.nfs + + Restart autofs: + + # systemctl restart autofs.service + + Try to access the share and notice that it won't automount: + + # ls -la /mnt/test + # + + You won't see any error messages unless you enable logging on autofs. + To do that, uncomment the "logging" line on /etc/autofs.conf and set it + to "debug". You will then see something like the following when you run + "journalctl -u autofs.service": + + get_portmap_client: error 0x3 getting portmap client + mount(nfs): no hosts available + + [ Where problems could occur ] + + The patch that fixes the problem has been posted in the upstream mailing + list by the maintainer, but hasn't been pushed to the git repository yet + (although the maintainer said he would do this soon). I have carefully + reviewed the patch and agree with the solution proposed; I have also + verified that autofs' dep8 tests are still passing. I find it unlikely + that the patch introduces a problem. + + If a regression happens, it will most likely manifest during the + automount process of NFSv4 shares. We can mitigate the problem by + suggesting the use of NFSv3 while we further investigate the issue, and, + worst case scenario, we can revert the current fix and work with + upstream to improve it. + + [ Original Description ] + I'm running a server which provides user home directories as NFSv4 shares. The clients mount these shares via automount + LDAP. Now I've updated one client from 20.04 to 22.04 (new installation from scratch). Setting up things as before, I cannot get the home directories to mount properly. The LDAP connection does work, and also manual mounting of the NFSv4 shares works. So the problem is in the automount part of the mechanism. The autofs package version on the 22.04 client is 5.1.8-1ubuntu1. Setting autofs to verbose mode, I get the following lines in /var/log/syslog on the client. automount[115692]: mount(nfs): nfs options="nfsvers=4,hard", nobind=0, nosymlink=0, ro=0 automount[115692]: get_nfs_info: called with host <...> proto 6 version 0x40 automount[115692]: get_portmap_client: error 0x3 getting portmap client automount[115692]: mount(nfs): no hosts available I think it is the same bug reported on the autofs mailing list here: https://www.spinics.net/lists/autofs/msg02389.html Apparently, it has been introduced in the transition of autofs from 5.1.7 to 5.1.8. A fix has been posted here: https://www.spinics.net/lists/autofs/msg02391.html It would be great if this fix could be included in Ubuntu 22.04, such that I can update my clients. As my setup should not be too exotic, I guess there are other people who will face the same problem when they are doing the Ubuntu update to the new LTS version.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1970264 Title: autofs fails to mount nfs4 shares with "error 0x3 getting portmap client" To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/autofs/+bug/1970264/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
