Re: cifs connection loss hangs

Steve French
2005-02-21T15:35:53Z

>Being a wireless user i experience the occasional connection loss due
>to walking out of range or something, recently after starting to use
>cifs mounts instead of smbfs, I've noticed that stuff tends to break
> if i lose connection.

cifs does support reconnection after tcp session drops (including
reattaching to the server shares and reopening open files, rewriting
cached data).

What kernel version ("cat /proc/version") or cifs vfs version ("modinfo
/lib/modules/<kernel ver>/kernel/fs/cifs/cifs.ko) are you running?

2.6.10 includes one fix for a race in the cifs reconnection logic (which
is included in cifs version 1.27 or later) and there was an earlier (and
more important) reconnection fix in cifs version 1.10 (I think that came
in mainline about at kernel version 2.6.6).

There are test patches (or in some cases a copy of the fs/cifs
directory) available for a few of the older but common kernels (SLES9,
SuseWorkstation 9.2, FC3 etc.) at
http://us1.samba.org/samba/ftp/cifs-cvs which include up to 2.6.10 level.

Note that you can view the state of cifs connections by "cat
/proc/fs/cifs/DebugData" (also interesting is "cat /proc/fs/cifs/Stats")
which will show the cifs tcp sessions, smb sessions and tree connection
(mount) and whether they need reconnection - it also shows the state of
any pending [cifs] operations on the network.