Re: cifs client caching wrong data

On Thu, 28 Jan 2010 23:05:17 +0100
Bjørn Tore Sund <[email protected]> wrote:

> 
> We distribute home directories to 600 linux clients using Samba and 
> cifs.  Since upgrading from Fedora 10 (mount.cifs from samba 3.2.15, 
> cifs kernel module version 1.54 on 2.6.27) to Fedora 12 (mount.cifs from 
> Samba 3.4.5, cifs kernel module version 1.60 on 2.6.31) on the clients 
> we have issues with updates on the file systems never being noticed on 
> the client site.
> 
> The quick test we run is to do:
> 
> mkdir a b c d e f g h i j k l m n o p q r s t u v w x; ls -a ?
> 
> Either that, or an immediately following:
> 
> rmdir ?; mkdir a b c d e f g h i j k l m n o p q r s t u v w x; ls -a ?
> 
> will trigger the issue.  Normally the first one and always the second 
> one will on all or most directories fail to show them containing "." and 
> "..".  The issue is wider, we're seeing file corruptions and "ls" 
> displaying the content of a different directory than the current working 
> directory but these are not predictably reproducable.  The behaviour is 
> similar to what we saw before we started mounting with nobrl two or 
> three years ago which leads me to suspect that nobrl somehow have 
> stopped being taken into account.  Once the client have started showing 
> wrong data for a directory no amount of prodding beyond unmounting and 
> remounting will make it show correct info again.
> 
> Server is the latest on SuSE Enterprise 10 (3.0.32), no changes have 
> been made to the configuration here, but we have tried 3.0.33 from RHEL5 
> and a self-compiled 3.4.5 on RHEL5 with no difference, nor did a manual 
> downgrade of mount.cifs to 3.2.15 on the clients have any effect. 
> Relevant parts of smb.conf on the server would be:
> 
>          enhanced browsing = yes
>          unix extensions = yes
>          kernel oplocks = yes
>          posix locking = yes
>          strict locking = no
>          locking = yes
>          wide links = yes
>          mangled names = no
>          delete readonly = No
> 
> [homes]
>          comment = Home Directories
>          valid users = %S
>          browseable = No
>          read only = No
>          inherit acls = Yes
> 
> mount.cifs is called with options nobrl and serverino.
> 
> It is entirely possible that this is a Fedora issue but I need to start 
> somewhere and this would be the place where people know the most about 
> the cifs client and might have seen something like this before.
> 
> -BT

It sounds like a similar issue as the one reported here:

http://bugzilla.kernel.org/show_bug.cgi?id=15088

It might be interesting to see whether the problems go away when you
mount with -o noserverino.

-- 
Jeff Layton <[email protected]>