NFS server: permission denied

[Jeff Macfarland]

NFS mounts to a RHEL 4u3-64 server receive "Permission denied" errors.

$ mount -t nfs -o rw nfsserver:/mnt/disk1 /mnt/disk1/
mount: nfsserver:/mnt/disk1 failed, reason given by server: Permission
denied

/etc/exports:
/mnt/disk1/     nfsclient(rw,no_root_squash)
/mnt/disk2/     nfsclient(rw,no_root_squash)

Restarting portmap, nfslock and nfs on nfsserver have no impact.
rpc.mountd _seems_ to allow it: (from messages)

May 13 15:01:57 nfsserver rpc.mountd: authenticated mount request from
nfsclient.domain.com:617 for /mnt/disk1 (/mnt/disk1)

One peculiar thing is that the 'sunrpc' module is not automatically
loaded on nfsserver after a reboot. Until I manually mount the
rpc_pipefs filesystem, I receive "RPC MTAB table not found" (not
verbatim). After I mount the pipefs filesystem, I no longer get this
error, but I still cannot mount any filesystems off of nfsserver.

mount -t rpc_pipefs sunrpc /var/lib/nfs/rpc_pipefs

One other piece of info that might be worthwile, every time I stop the
nfs services on the server, in messages there are a few lines that look
strange:

May 13 15:13:12 nfsserver kernel: nfsd: last server has exited
May 13 15:13:12 nfsserver kernel: nfsd: unexporting all filesystems
May 13 15:13:12 nfsserver kernel: rpciod: active tasks at shutdown?!
May 13 15:13:12 nfsserver kernel: RPC: error 5 connecting to server
localhost
May 13 15:13:12 nfsserver kernel: RPC: failed to contact portmap (errno -5).
May 13 15:13:12 nfsserver nfs: nfsd shutdown succeeded

Output from 'rpcinfo -p nfsserver' from client:
   program vers proto   port
    100000    2   tcp    111  portmapper
    100000    2   udp    111  portmapper
    100024    1   udp  32798  status
    100024    1   tcp  32838  status
    100011    1   udp    644  rquotad
    100011    2   udp    644  rquotad
    100011    1   tcp    647  rquotad
    100011    2   tcp    647  rquotad
    100003    2   udp   2049  nfs
    100003    3   udp   2049  nfs
    100003    4   udp   2049  nfs
    100003    2   tcp   2049  nfs
    100003    3   tcp   2049  nfs
    100003    4   tcp   2049  nfs
    100021    1   udp  32799  nlockmgr
    100021    3   udp  32799  nlockmgr
    100021    4   udp  32799  nlockmgr
    100021    1   tcp  32839  nlockmgr
    100021    3   tcp  32839  nlockmgr
    100021    4   tcp  32839  nlockmgr
    100005    1   udp    660  mountd
    100005    1   tcp    663  mountd
    100005    2   udp    660  mountd
    100005    2   tcp    663  mountd
    100005    3   udp    660  mountd
    100005    3   tcp    663  mountd

Hostname resolution works from both machines and both are on the same
network. No iptables firewall is in place. The nfsclient can mount nfs
mounts from other nfs servers, but no client can mount from this server.

Things Ive tried:

Specifying the fqdn in the mount command
Specifying nfsvers=3, udp, tcp
Replacing 'nfsclient' with '*' in /etc/exports
Restarting portmap, nfslock, nfs after every change
Running exportfs -r after every change to /etc/exports

What am I missing?

-- 
Jeff Macfarland (jmacfarland at nexatech.com)
Nexa Technologies - 972.747.8879
Unix Administrator
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