On Wed, Sep 07, 2005 at 10:15:37PM +0200, Axel Thimm wrote: > After having setup our workarounds for NFS we are very happy with how > it's working. Now we're looking at Samba. > > But we have quite a showstopper right at the beginning. The smb/cifs > clients, be it smbclient or Windows XP, don't like their TCP stream > being resetted and don't retry/reconnect (contrary to NFS). > > It looks like the protocol has no considerations for retries above the > TCP/IP level. So when the TCP stream is torn on the server's side due > to relocation (either due to crash/fencing or soft) any client > smb/cifs activity is broken at that time. > > This means that any data transfer via smb/cifs shares during the > relocation will fail, and there is nothing we can do on the server's > side. Or is there? Windows clients will reconnect to the same server, and so will smbfs and cifs-vfs. I just tested this. On a W/XP box I browsed through some directories on a share served by Samba. I then shut Samba down, and tried viewing some different subdirectories of the same share. Windows coughed up an error dialog. I then restarted Samba and Windows got happy again. I could browse through all of the subdirectories in the share. We've talked about Samba on GFS within the Samba Team, and various members have done some digging into the problem (Volker most recently, if I'm not mistaken). Samba must maintain a certain amount of state information internally--including name mangling, locking, and sharing information that--is peculiar to Windows+DOS+OS2 semantics. The problem is ensuring that Samba's state information is also shared across the GFS nodes. I've not had time to keep up with this development thread, but I know that the folks working on Samba-4 are aware of the issues involved. Chris -)----- -- "Implementing CIFS - the Common Internet FileSystem" ISBN: 013047116X Samba Team -- http://www.samba.org/ -)----- Christopher R. Hertel jCIFS Team -- http://jcifs.samba.org/ -)----- ubiqx development, uninq. ubiqx Team -- http://www.ubiqx.org/ -)----- crh@xxxxxxxxxxxx OnLineBook -- http://ubiqx.org/cifs/ -)----- crh@xxxxxxxxx -- Linux-cluster@xxxxxxxxxx http://www.redhat.com/mailman/listinfo/linux-cluster
