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I have a problem involving and NFS4 server and client. The problem is that when the client has the exported filesystem mounted and the server is rebooted, the reboot will hang with a console messages stating:

Unmounting file systems: umount /nfs4exports/home: device is busy
umount: /nfs4exports/home: device is busy
/nfs4exports/home:  rcercrcrcrcrcrcrcrcrcrcrcrcrcrcrcrcrcrcrcr.......
INIT: no more processes left in this runlevel
portmap: RPC call returned error 101
RPC: failed to contact portmap (error -101)
nfsd: last server has exited

If the client, which is CentOS 5, does not have the export mounted, the server will reboot cleanly as expected.

The server is CentOS 5.8 up to date as of today. The exports file has the following lines:


The client is mounting the /home directory from the command line with

mount -t nfs4 -o soft,intr /media

cat /proc/mounts shows: /media nfs4 rw,vers=4,rsize=1048576,wsize=1048576,soft,intr,proto=tcp,timeo=600,retrans=3,sec=sys,addr= 0 0

Anyone have thoughts on why this NFS4 server is having problems unmounting its own filesystems when shutting down only when a client has it mounted?

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