Bug 56665

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Description of problem:
I just installed RH7.1 on a machine, upgraded to the last errata 
versions, and installed the 2.4.9-12smp kernel.  The machine has an
internal SCSI disk and external IDE->SCSI Raid.  I converted all 
partitions except / to ext3 which are exported.  I start nfs and can
mount the exports just fine from a couple of clients.  I start a 
script that loops over many tens of clients to mount a export off
the server.  After about ten or so, mounts stop working and I get
I/O errors.  Unmounting from a previously successful client and 
retrying the mount all fails.

I can '/etc/init.d/nfs restart' and things start working again for
another few minutes.

I downgrade to the RH 2.4.7-2.9 kernel (which I patched for ext3) and
the problem goes away.
Mounts of the ext2 root volume also fail so I don't think it is an
ext3 problem.

I tried upgrading nfs-utils and mount to rawhide versions but problem
did not go away.


Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1. Upgrade to 2.4.9-12 kernel
2. Export several mount points
3. Mount exports from serveral clients till you get I/O error
   and server refuses to give more mounts
	

Actual Results:  Could no longer mount NFS exported volumes off server

Expected Results:  SHould have been able to mount exported NFS volumes

Additional info:

When the problem first starts, you will see messages like this in
syslog:

Nov 23 12:36:46 monte rpc.mountd: authenticated mount request from
132.183.203.39:1022 for /local_mount/homes/monte/1
(/local_mount/homes/monte/1) 
Nov 23 12:36:46 monte last message repeated 19 times

However, soon no messages appear from other attempted mounts so
rpc.mountd is probably completely locked up.

Here is the /etc/exports file:
===============
/local_mount/homes/monte/1 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/1 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/2 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/3 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/4 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/5 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/6 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/7 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/8 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/local_mount/space/monte/9 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

/export/redhat-7.1 \
  @all(rw) \
  192.168.100.0/255.255.255.0(rw,no_root_squash,insecure)

===========
The machine is a master of batch (beowulf) cluster so has
two network devices with batch nodes on 192.168.100.*