[linux-cifs-client] error while writing large file to Windows share

[Noah Romer]

Ok, here's the setup. We have a backup process running on a Fedora Core 6 box 
(2.6.18-1.2257smp kernel, samba-3.0.23c-1.fc5 userland code) that writes 
several files to a temporary directory on a Windows share and then tars them 
all up into a single tarball, also on the Windows share. When it gets about 
63GB-76GB into writing the tarball, we get an error the causes it to be 
incomplete/corrupt.

This shows up on the console as a tar error:
tar: var.tar: File shrank by 17045487616 bytes; padding with zeros
tar: Error exit delayed from previous errors

The tar error corresponds with an series of error messages 
in /var/log/messages:

Oct 26 11:42:50 [system name] kernel:  CIFS VFS: server not responding
Oct 26 11:42:50 [system name] kernel:  CIFS VFS: server not responding
Oct 26 11:42:50 [system name] kernel:  CIFS VFS: No response to cmd 47 mid 125
93
Oct 26 11:42:50 [system name] kernel:  CIFS VFS: No response to cmd 47 mid 140
04
Oct 26 11:42:53 [system name] kernel:  CIFS VFS: No response to cmd 47 mid 170
26
Oct 26 11:42:53 [system name] kernel:  CIFS VFS: Write2 ret -11, written = 0
Oct 26 11:42:53 [system name] kernel:  CIFS VFS: Write2 ret -9, written = 0

[other log messages snipped]

Oct 26 14:28:00 [system name] kernel:  CIFS VFS: Send error in read = -12
Oct 26 14:28:39 [system name] last message repeated 2 times
Oct 26 14:31:04 [system name] kernel:  CIFS VFS: Send error in read = -12
Oct 26 14:33:32 [system name] kernel:  CIFS VFS: Send error in read = -12
Oct 26 14:34:53 [system name] last message repeated 4 times
Oct 26 14:36:30 [system name] last message repeated 2 times
Oct 26 14:39:29 [system name] last message repeated 4 times
Oct 26 14:40:47 [system name] last message repeated 3 times
Oct 26 14:40:47 [system name] last message repeated 2 times

Because tar is doesn't report its error message immediately I can't be sure 
which of the cifs error sequences corresponds directly to it.

Any ideas on what's causing this, or suggestions for further debugging? This 
is occuring on a customer's network, so I can't get all ham-fisted but I'm 
willing to dig for further info if it will help.

Thanks,
Noah Romer
-- 
Noah Romer <nromer at arcmailtech.com>
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