update-nfs-utils: Disable nfs version 3

We use nfs version 4 only. Disable unused version 3, to make things
simpler.

scripts/update-nfs-utils.sh

@@ -1,9 +1,5 @@
 #! /bin/bash
 
-# Note, you are doing this to a live nfs server, writes will be blocked
-# for 90 seconds.
-#
-
 set -v
 
 bee remove portmap-6.0-0.x86_64
@@ -67,7 +63,7 @@ After=statd.service local-fs.target proc-fs-nfsd.mount var-lib-nfs-rpc_pipefs.mo
 ExecStartPre=/bin/mkdir -p /var/lib/nfs/v4recovery
 ExecStartPre=/usr/sbin/exportfs -ra
 ExecStart=/usr/sbin/rpc.mountd --foreground --manage-gids
-ExecStartPost=/usr/sbin/rpc.nfsd 64 ; /usr/sbin/sm-notify
+ExecStartPost=/usr/sbin/rpc.nfsd -N 3 64 ; /usr/sbin/sm-notify
 ExecReload=/usr/sbin/exportfs -ra
 ExecStopPost=/usr/sbin/rpc.nfsd 0 ; /usr/sbin/exportfs -ua
 Restart=always
@@ -93,6 +89,8 @@ systemctl enable rpcbind.socket
 # This implies, we can't just push the changes around from the distmaster,
 # but have to execute this script on every node.
 #
+# However, doing this on a live nfs server, will block writes for
+# 90 seconds (measured: 1 min 45 seconds).
 
 systemctl daemon-reload
 systemctl restart systemd-logind.service   # maybe still required after daemon-reload