Can't mount NFS share on Mac OS Big Sur shared from Ubuntu 21.04 - rpc.statd not running

I have set up a NFS share on a Ubuntu 21.04 VM, which I want to mount on a Mac OS Big Sur client.

The share lists fine, when checked with showmount, but the mount fails:

andi@iMac-Pro Projects % showmount -e 10.116.0.108
Exports list on 10.116.0.108:
/srv/nfsv4/vsc-docker-projects      10.116.0.0/24
/srv/nfsv4                          10.116.0.0/24

andi@iMac-Pro Projects % sudo mount -t nfs 10.116.0.108:/srv/nfsv4/vsc-docker-projects /Users/andi/Documents/Projects/vsc-docker-projects
mount_nfs: can't mount with remote locks when server (10.116.0.108) is not running rpc.statd: RPC prog. not avail
mount: /Users/andi/Documents/Projects/vsc-docker-projects failed with 74
andi@iMac-Pro Projects %

I have following config on the server:

$ cat /etc/exports
/srv/nfsv4   10.116.0.0/24(rw,sync,root_squash,no_subtree_check,fsid=0)
/srv/nfsv4/vsc-docker-projects 10.116.0.0/24(rw,sync,root_squash,no_subtree_check)

$ cat /etc/fstab
/home/andi/vsc-docker-projects /srv/nfsv4/vsc-docker-projects none bind 0 0

I understand the problem is related to rpc.statd, wich is installed on the system:

$ which rpc.statd
/usr/sbin/rpc.statd

...but obvioulsy not running:

$ ps -ef | grep rpc
root         407       2  0 04:00 ?        00:00:00 [rpciod]
_rpc         648       1  0 04:00 ?        00:00:00 /sbin/rpcbind -f -w
root        2361       1  0 04:21 ?        00:00:00 /usr/sbin/rpc.idmapd
root        2362       1  0 04:21 ?        00:00:00 /usr/sbin/rpc.mountd --manage-gids
andi        2509    1255  0 04:32 pts/0    00:00:00 grep --color=auto rpc

Also starting is not possible:

$ sudo systemctl start rpc.statd
Failed to start rpc.statd.service: Unit rpc.statd.service not found.

$ service start rpc.statd
start: unrecognized service

I there just missing a service file in /etc/systemd/system/? The VM is really newly installed and I just updated it with apt, installed Docker. I can't imagine I broke it in this short time.

Any idea what I could try next? Thanks in advance.

Searching around a bit, I found a posting pointing into the right direction.

Activating the service did the trick:

# check status on rpcbind.service
systemctl status rpcbind.service
systemctl reenable rpcbind.service
systemctl restart rpcbind.service

# check status on rpc-statd.service
systemctl status rpc-statd.service
systemctl reenable rpc-statd.service
systemctl restart rpc-statd.service

Now I get a message related to rights, which for sure is a step forward:

andi@iMac-Pro Projects % sudo mount -t nfs 10.116.0.108:/srv/nfsv4/vsc-docker-projects /Users/andi/Documents/Projects/vsc-docker-projects
Password:
mount_nfs: can't mount /srv/nfsv4/vsc-docker-projects from 10.116.0.108 onto /Users/andi/Documents/Projects/vsc-docker-projects: Operation not permitted
mount: /Users/andi/Documents/Projects/vsc-docker-projects failed with 1
andi@iMac-Pro Projects %

A some additions in the server's /etc/exports did the trick:

/srv/nfsv4/vsc-docker-projects 10.116.0.109/24(rw,sync,root_squash,no_subtree_check,anonuid=1000,anongid=1000,insecure)

The share is only exposed to one another host. Hence, insecure should be fine.

Now just add an entry in the clients /etc/fstab and we are ready to roll:

10.116.0.108:/srv/nfsv4/vsc-docker-projects     /Users/andi/Documents/Projects/vsc-docker-projects      nfs auto 0 0