----- "Michael Goldish" <mgoldish@xxxxxxxxxx> wrote: > From: "Michael Goldish" <mgoldish@xxxxxxxxxx> > To: "Feng Yang" <fyang@xxxxxxxxxx> > Cc: autotest@xxxxxxxxxxxxxxx, kvm@xxxxxxxxxxxxxxx > Sent: Wednesday, October 20, 2010 6:48:42 PM GMT +08:00 Beijing / Chongqing / Hong Kong / Urumqi > Subject: Re: [PATCH] KVM Test: add -w parameter in nc command in kvm_utils.py > > On 10/20/2010 12:18 PM, Feng Yang wrote: > > > > ----- "Michael Goldish" <mgoldish@xxxxxxxxxx> wrote: > > > >> From: "Michael Goldish" <mgoldish@xxxxxxxxxx> > >> To: "Feng Yang" <fyang@xxxxxxxxxx> > >> Cc: autotest@xxxxxxxxxxxxxxx, kvm@xxxxxxxxxxxxxxx > >> Sent: Wednesday, October 20, 2010 5:11:32 PM GMT +08:00 Beijing / > Chongqing / Hong Kong / Urumqi > >> Subject: Re: [PATCH] KVM Test: add -w parameter in nc command in > kvm_utils.py > >> > >> On 10/20/2010 08:55 AM, Feng Yang wrote: > >>> If a connection and stdin are idle for more than timeout seconds, > >>> then the connection is silently closed. withou this paramter, > >>> nc will listen forever for a connection. This may cause our test > >>> hang. redmine issue: > >>> http://redmine.englab.nay.redhat.com/issues/show/6947 > >>> Add -w parameter should fix this issue. > >>> > >>> Signed-off-by: Feng Yang <fyang@xxxxxxxxxx> > >>> --- > >>> client/tests/kvm/kvm_utils.py | 2 +- > >>> 1 files changed, 1 insertions(+), 1 deletions(-) > >>> > >>> diff --git a/client/tests/kvm/kvm_utils.py > >> b/client/tests/kvm/kvm_utils.py > >>> index a51c857..526d38d 100644 > >>> --- a/client/tests/kvm/kvm_utils.py > >>> +++ b/client/tests/kvm/kvm_utils.py > >>> @@ -733,7 +733,7 @@ def remote_login(client, host, port, > username, > >> password, prompt, linesep="\n", > >>> elif client == "telnet": > >>> cmd = "telnet -l %s %s %s" % (username, host, port) > >>> elif client == "nc": > >>> - cmd = "nc %s %s" % (host, port) > >>> + cmd = "nc %s %s -w %s" % (host, port, timeout) > >>> else: > >>> logging.error("Unknown remote shell client: %s" % > client) > >>> return > >> > >> I don't understand how remote_login() can stall here. > >> kvm_utils._remote_login() doesn't rely on nc's self-termination. > If > >> no > >> shell prompt is available after 10 seconds, nc is forcefully > >> terminated > >> and _remote_login() fails. If it somehow stalls this might > indicate > >> a > >> bug somewhere. > > It is really rarely reproduce. Only meet this issue when guest panic > or core dump. > > nc stall. Do not know why it is not terminated after 10s. > > > > I think -w parameter is helpful in this situation. > > If it does not cause other issue, we'd better add -w in nc > command. > > > > Thanks for your command. What do you think? > > > > Feng Yang > > Adding -w 10 may cause trouble. If a good functional session is idle > for more than 10 seconds during a test, it will be closed. For > example, > if you run a command that takes more than 10 seconds to complete, and > produces no output while it runs, the session will be closed. Seems the session also will be closed in our current code in this situation. If no output for 10s, _remote_login() will return False. Then session will be closed in remote_login(). I have run some cases, it works well. But I think we'd better first post this code, in case it really cause trouble. I will do more test on it. > > Also, I doubt it'll solve the problem you've experienced. As it is, > the > code should (and usually does) properly handle the case of nc not > terminating. > > If you manage to reproduce this again please save the log so I can > have > a look at it. When meet this issue again, I will send log to you. Thanks for your help! Feng Yang > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
