On Sunday, 18 August 2019 09:30:36 BST Adam Carter wrote:
> Is the output of 'mount | grep nfs' the same on the two client machines?
$ mount | grep nfs
nfsd on /proc/fs/nfsd type nfsd (rw,nosuid,nodev,noexec,relatime)
nfs4 requires less ports than nfs3, just 2049 and something for mountd (IIRC). Try using nfs4 and setting up the firewall for 2049 and 32767 from your OPTS_RPC_MOUNTD="-p 32767" setting. From tcpdump, where .2 is the client and .250 is the server;
192.168.1.2.949 > 192.168.1.250.2049: Flags [S]
but the other session is
192.168.1.250.730 > 192.168.1.2.40895: Flags [S]
ie a low port on the nfs server makes a connection back to the client, so its quite unconventional
FYI, here's what one of mine looks like
$ mount | grep nfs
192.168.1.250:/export/public on /mnt/public type nfs4
(ro,noatime,vers=4.0,rsize=1048576,wsize=1048576,namlen=255,soft,proto=tcp,timeo=600,retrans=2,sec=sys,clientaddr=192.168.1.251,local_lock=none,addr=192.168.1.250,_netdev)
$ grep nfs /etc/fstab
192.168.1.250:/export/public /mnt/public nfs4 ro,_netdev,vers=4.0,soft,noatime 0 0