[rancid] rancid "losing" characters

[heasley]

Fri, Oct 18, 2013 at 09:51:29AM -0400, Stephen Griffin:
> We had reduced the send_human timers because of internal user complaints
> that it was too slow. I went back to the stock value and it dramatically
> reduced (although didn't eliminate entirely) the lost characters, so it
> appears to be buffer overflows. It is just odd because the older version we
> had didn't (ttbomk) use send_human.

sigh.  unless there is a bug in tcl/expect, i don't know why that would
happen.  when the login scripts get a prompt, they try to build a more
complete prompt for more assurance that it doesnt match stuff in the
output of commands.  is it building something reasonable from your prompts
(flogin -d -c somecmd).  i do not see anything about buffers in the expect
changelog that seems like it'd affect 5.43.  i didnt look at tcl.

> Stephen
> 
> 
> On Wed, Oct 16, 2013 at 3:28 PM, heasley <heas at shrubbery.net> wrote:
> 
> > Mon, Oct 07, 2013 at 10:30:02AM -0400, Stephen Griffin:
> > > So, I have a version of rancid 2.3.8 installed, and I've been noticing on
> > > some of our Foundry/Brocade gear that some commands are failing because a
> > > character is lost.. for example, skip-page-dilay instead of
> > > skip-page-display.
> > >
> > > Our prior version of rancid was quite old (so old that no one really was
> > > quite sure of what version it was), and we don't recall seeing this
> > > behaviour. It feels like a buffer being exhausted, but 2.3.8 uses
> > > send_human, which should be slowing things down.
> > >
> > > The version of expect wasn't changed, and is 5.43.0
> > >
> > > We did fold in some of our older custom changes, but I have a difficult
> > > time believing those would impact lost characters.
> > >
> > > Has anyone run into this or something similar?
> >
> > there once was a problem with hpuifilter that caused this, but that would
> > not affect foundry, only hp/hlogin.  perhaps that was part of your changes?
> >
> > otherwise, i'd suspect expect.
> >
> > > I did a test run, by sending "show 802" to a bunch of devices, and came
> > up
> > > with:
> > >       1 e
> > >     145 exit
> > >       1 sh
> > >       1 show 02
> > >       1 show 80
> > >     145 show 802
> > >       1 show802
> > >       1 skip-page-ay
> > >     148 skip-page-display
> > >
> > > Thanks,
> > > Stephen
> > > --
> > > Stephen A. Griffin
> > > Network Engineer
> > > Google Acquisition Netops
> >
> > > _______________________________________________
> > > Rancid-discuss mailing list
> > > Rancid-discuss at shrubbery.net
> > > http://www.shrubbery.net/mailman/listinfo/rancid-discuss
> >
> >
> 
> 
> -- 
> Stephen A. Griffin
> Network Engineer
> Google Acquisition Netops