[cifs-protocol] [REG: 110120160951867] Requesting clarification of CIFS client timeout behavior

[Jeff Layton]

On Wed, 01 Dec 2010 16:08:32 -0600
"Christopher R. Hertel" <crh at samba.org> wrote:

[...]

> 
> Probably needs two tests.  One to see what happens if the (single)
> connection is lost, and another to see what happens if a single operation
> takes a very, very long time to complete (as you describe).
> 

I did an experiment with this on win2k8. I first doctored an smbd to
discard write requests. When I try to copy a file to this host (via
copy.exe), the server usually waits a little while (the time seems to
vary between 30-60s or so), sends a single echo request and then
reconnects the socket if it still doesn't get a write reply in about
30s. copy.exe then says "The specified network name is no longer
available." Heh.

That said, the behavior seems to be really inconsistent. In at least
one case, no echo was sent and the socket was shut down <30s after the
write request was sent.

The timeout before sending an echo also seems to vary quite a bit. My
suspicion is that that indicates that the client has the echo ping on a
separate timer, and just selectively sends it whenever the timer pops
based on certain criteria.

-- 
Jeff Layton <jlayton at samba.org>