Re: two problems with OpenSSH and scp

From: Sergey Malov (sergey.malov@ssmb.com)
Date: 03/06/02 

From: sergey.malov@ssmb.com (Sergey Malov)
Date: 6 Mar 2002 10:38:50 -0800

Thanks for response, I thought I'll never get any :-).
Problem that most of what you've described I did and traffic still
look normal to me. I'will probably try to roll back changes to get
what I had before and then analyse traffic statistics before and after
changes.
Problem with scp (infinite coping) is very weird. I have local ssh
guru, he never saw anything like this.
Oh, well...

Thanks

Sergey

"iLiad" <brad_grandorff@hotmail.com<removeme>> wrote in message news:<3c85bd5c_6@news1>...
> And.....I will add....obviously you will not be able to decode the actual
> traffic of the SCP'ed connection.
> But, you need to look for re-transmits, failed TCP connections, collisions,
> CRC errors, or anything that your
> traffic analyzer will show you.
> Start eliminating the layers of the OSI model to ensure it isn't an actual
> network related problem. I'm not sure of your
> level of expertise in this area, but it isn't uncommon to have a duplex
> mismatch on a network, which will cause MASSIVE
> collisions is you are on a switch. If you are on a hub, then it can be
> similar depending on what type of nic you are using.
>
>
> Well enough said.
> iLiad
>
>
> "iLiad >" <brad_grandorff@hotmail.com<removeme> wrote in message
> news:3c85ba07_4@news1...
> > Sergey,
> > I can only theorize on the problems. But, it actually sounds like some of
> > this may be coincidental.
> > It may be that you actually have network problems causing what you see.
> > SCP is, of course, encrypting the information across the wire. The higher
> > the encryption, the more data flowing.
> > If there are layer 1/2 problems on your network, such as collisions, or an
> > invalid duplex setting, then you are exponentially (well, maybe not that
> > bad)
> > increasing the chances of problems happening when using SCP. Meaning,
> > information that is NOT encrypted would have a less likely chance of havin
> > the collision or problem as it would take less data to send. BUT that is a
> > VERY vague statement as it depends on the length of the cable, size of the
> > frame (assuming Ethernet), etc. etc.
> > Of course, the reason I say it may be coincidence, is that you are having
> > the problem with FTP as well. And FTP should be plain, and simple.
> > To troubleshoot, I would definitely get a packet analyzer out and watch
> the
> > traffic. Something like Ethereal, tcpdump, or snoop (assuming you are
> using
> > the unices) and of course, Ethereal will work on the WIN32 platform.
> > You will need to look for CRC errors. I'd bet a dollar that is what is
> going
> > on ;-)
> >

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