On Sat, 4 Dec 2010 06:25:07 -0600 Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx> wrote: > On Sat, Dec 4, 2010 at 5:44 AM, Jeff Layton <jlayton@xxxxxxxxx> wrote: > > > On Sat, 4 Dec 2010 09:13:21 +0100 > > Volker Lendecke <Volker.Lendecke@xxxxxxxxx> wrote: > > > > > On Fri, Dec 03, 2010 at 09:54:13PM -0600, Christopher R. Hertel wrote: > > > > That may seem to be in the "who cares" category, since those old > > transports > > > > are essentially dead (much more dead than NBT, or even NBF). > > Unfortunately, > > > > the code to handle the old transports is still there in Windows, so > > there > > > > are behaviors -- things like the timeouts you're talking about and the > > weird > > > > VC=0 shutdown behvior -- that exist because of these old disused > > transports. > > > > > > VC=0, how does Windows treat this facing NAT (masquerading) > > > networks? I've done tests in the past where Windows killed > > > valid connections from behind a NAT box when a new client > > > came in. > > > > > > Volker > > > > It seems like the best way to deal with this on the server side with > > direct hosted TCP would be to treat VC=0 like any other VC number > > (MS-CIFS says that this is allowed). > > > > Ideally any new connection event from a host however should make the > > server check the validity of any other connection from the same host. > > That way you could release resources held by dead connections in case > > the new one is a reconnect and needs to reclaim state. > > > > The question is how to check that validity. Unfortunately, the best you > > can probably do is rely on TCP keepalives. > > > > -- > > Jeff Layton <jlayton@xxxxxxxxx> > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-cifs" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > > Is SMB Echo command the only way to determine whether to reconnect or not? > The assumption here is SMB server is unresponsive. > There could be other circumstances on the server box (or even client box) > that are > slowing down the SMB server responses such as slow network, slow network > stack, > memory pressure etc. > So server could be fine all along and yet client would ask for reconnection! I think it's the best mechanism that the protocol has. If we aren't going to use SMB echoes to detect an unresponsive server, then what would you suggest? I don't think we can make calls wait indefinitely for a response without a mechanism to determine when the server is gone and attempt to reestablish the connection to it. -- Jeff Layton <jlayton@xxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
