Need NFS v2 (slackware 7.X) machine to mount a NFS partition on slackware64 15.0 server

I have a museum piece server running slackware 7.X NFS v2 (2.2.25 kernel) that I intend to migrate old custom applications. I never got around to updating this production server as life got busy and it was never a priority. Now it is.

In the meantime I will need to mount NFS partitions that reside a slackware64 15.0 server (NFS v4 & 5.15.117 kernel) from the slackware 7.X machine running NFS v2.

I had been previously been able to mount NFS partitions that resided on a slackware64 14.1 server (NFS v4 & 3.10.107 kernel) from the slackware 7.X machine running NFS v2.

Both the v15.0 & v14.1 servers are setup identically NFS configuration wise and /etc/nfsmount.conf has a default v3. I can mount the slackware64 14.1 NFS partition but not the slackware64 15.0 NFS partition.

The /etc/exports are set up identically and the /etc/fstab are done the same way.

Is the slackware64 15.0 NFS no longer support NFS v2?

For backups I can mount partitions on the slackware 7.X machine from the slackware64 15.0 reliably.

The /etc/fstab on the slackware 7.X server has been setup:
Quote:

s150_server:/data /data_s150 nfs rsize=8192,wsize=8192,rw,hard,intr 1 2 s141_server:/data /data_s141 nfs rsize=8192,wsize=8192,rw,hard,intr 1 2

The /etc/exports on the slackware64 14.1 server has been setup:
Quote:

/data 192.168.4.100(rw,sync,no_root_squash,no_subtree_check)

The /etc/exports on the slackware64 15.0 server has been setup:
Quote:

/data 192.168.4.100(rw,sync,no_root_squash,no_subtree_check)

where 192.168.4.100 is the slackware 7.X server IP address

I gather I am missing something subtle.

Thanks