NFS Server is not responding / Alive again

[Brandon]

Guys,

Can anyone explain to me how to diagnose this issue further? I'm not quite 
sure whats causing this problem, and I'm not sure how much of a problem it 
is either.  I'm getting alot of nfs server hangs in the logs:

cat /var/log/messages
Jul  2 22:20:47 be-3 last message repeated 11 times
Jul  2 22:20:51 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  2 22:20:52 be-3 last message repeated 5 times
Jul  3 00:26:13 be-3 kernel: nfs server bluearc:/smtp: not responding
Jul  3 00:26:17 be-3 last message repeated 4 times
Jul  3 00:26:43 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  3 00:26:43 be-3 last message repeated 4 times
Jul  3 06:06:19 be-3 kernel: nfs server bluearc:/smtp: not responding
Jul  3 06:06:31 be-3 kernel: nfs server bluearc:/smtp: not responding
Jul  3 06:06:32 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  3 06:06:32 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  3 06:06:32 be-3 kernel: nfs server bluearc:/smtp: not responding
Jul  3 06:06:32 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  3 06:06:32 be-3 kernel: nfs server bluearc:/smtp: not responding
Jul  3 06:06:32 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  3 06:06:32 be-3 kernel: nfs server bluearc:/smtp: not responding
Jul  3 06:06:35 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  3 06:39:09 be-3 kernel: nfs server bluearc:/smtp: not responding
Jul  3 06:39:11 be-3 last message repeated 8 times
Jul  3 06:39:12 be-3 kernel: nfs server bluearc:/smtp: is alive again
Jul  3 06:39:14 be-3 last message repeated 8 times


My /etc/fstab looks like this:
bluearc:/smtp           /bluearc/smtp   nfs 
rw,nfsv3,tcp,noauto,-w32768,-r32768,intr,nosuid 0       0

Output of NFS Stat looks like this:

nfsstat
Client Info:
Rpc Counts:
   Getattr   Setattr    Lookup  Readlink      Read     Write    Create 
Remove
   5838941   9856787  53208796       196  23086347  12329026   7210077 
48313
    Rename      Link   Symlink     Mkdir     Rmdir   Readdir  RdirPlus 
Access
   7220894         0         0        89        75   3096988         0 
74732115
     Mknod    Fsstat    Fsinfo  PathConf    Commit
         0   4311937         7         0         0
Rpc Info:
  TimedOut   Invalid X Replies   Retries  Requests
         0         0         0       412 200940588
Cache Info:
Attr Hits    Misses Lkup Hits    Misses BioR Hits    Misses BioW Hits    Misses
633693347  52472488 394292901  53208796  86802445  23086337  35572967  12329026
BioRLHits    Misses BioD Hits    Misses DirE Hits    Misses
  60679022       196   5566347   3097022   4311900        18

uname -a
FreeBSD be-3 5.4-RELEASE FreeBSD 5.4-RELEASE #2: Mon Jun 20 20:20:21 MDT 
2005     root at be-3:/usr/src/sys/i386/compile/MYKERNEL  i386

Any help you guys can provide is appreciated.

Brandon