Public bug reported: nfs-server.service has insufficient dependencies to start correctly in a setting where the nfs exports list contains DNS host names (not in local hosts file) or netgroups served via network (for example sssd).
Typical failures listed by systemctl status nfs-server.service are: Mar 08 14:16:52 server.example.com exportfs[844]: exportfs: Failed to resolve client1.example.com Mar 08 14:16:52 server.example.com exportfs[844]: exportfs: Failed to resolve client2.example.com Our workaround is to add the appropriate dependecies in /etc/systemd/system/nfs-server.service.d/dependencies.conf like so: ----------------------8<---------------------------- [Unit] # nfs-server.service runs exportfs on startup, thus we need to be able to # do host and netgroup lookups which requires network to be online. After=network-online.target nss-lookup.target nss-user-lookup.target ----------------------8<---------------------------- While nfs-server.service do depend on network.target, that only means that the network has been configured. On physical hardware it can take significantly longer for the network to come online (8+ seconds for our 10G NICs). Also note that we configure static IP:s via systemd-networkd, things might behave differently when using DHCP, network-manager etc. In any case, depending on network.target is almost always wrong, and network-online.target is usually the right one. nss-lookup.target is needed to ensure that DNS resolution works, and nss-user-lookup.target is the best approximation to ensure that netgroup resolution via sssd or equivalent works. Usually things "just works" even without these dependencies, but to ensure correct startup they should be present. It should be noted that this seems to once have been fixed in Ubuntu, but has been lost along the way for quite some time. When googling I find for example https://code.launchpad.net/~ubuntu-branches/ubuntu/wily /nfs-utils/wily-201507271018/+merge/265946 that fixes the network.target vs network-online.target dependency, but it has since been lost in the wind it seems. ** Affects: nfs-utils (Ubuntu) Importance: Undecided Status: Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1918141 Title: nfs-server.service needs name resolution and network online To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nfs-utils/+bug/1918141/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
