On Tue, 22 Feb 2000, George Bonser wrote:
> On Tue, 22 Feb 2000, Keith G. Murphy wrote:
>
> > I have seen several postings on this list about your problem, but never
> > any response when asked (by John Hasler) for details. Maybe you go
> > offline with "gurus" with your problem, but I suspect you'd be better
> > served, if you are sincerely interested in getting Debian to do this, if
> > you persisted with the list and offered us some details like: logs; type
> > of modem; dialup strings that Debian (and Corel) are using. And what's
> > your provider; maybe someone else has that one and knows the pitfalls.
> > Hit-and-run won't get it; it only frustrates everybody.
> >
>
>
> Try:
>
> echo 0 >/proc/sys/net/ipv4/tcp_timestamps
>
> OR
>
> Turn off all ppp header compression.
>
> Hanging/balky ppp connection are usualy the result of a combination of tcp
> timestamps and header compression. There is something with the timestamps
> that tickles a bug in the compression. The timestamps are optional and may
> be turned off. I suspect Corel did one or both of these things in their
> default ppp setup.
>
>
Hi, George,
I've discussed this ppp problem with others on this list before. And it
looks like this problem occurs only when using PCMCIA modems from my
experience.
The first weird thing I noticed is the content in ppp.log:
Feb 10 22:14:28 newton pppd[449]: sent [LCP EchoReq id=0x8 magic=0xa88cda89]
Feb 10 22:14:28 newton pppd[449]: rcvd [LCP EchoRep id=0x8 magic=0x0]
Feb 10 22:14:58 newton pppd[449]: sent [LCP EchoReq id=0x9 magic=0xa88cda89]
Feb 10 22:14:58 newton pppd[449]: rcvd [LCP EchoRep id=0x9 magic=0x0]
Feb 10 22:15:28 newton pppd[449]: sent [LCP EchoReq id=0xa magic=0xa88cda89]
Feb 10 22:15:58 newton pppd[449]: sent [LCP EchoReq id=0xb magic=0xa88cda89]
Feb 10 22:16:28 newton pppd[449]: sent [LCP EchoReq id=0xc magic=0xa88cda89]
That is, the remote ppp server stop to response to my Echo request and the
up-link communication stops at the same time. It seems (from the content
of my ppp.log) that after 4 un-acknowledged Echo requests, the pppd would
begin to send link termination requests. After 10 un-acknowledged link
termination requests, the pppd demean would die automatically. Do you
think this is the problem you mentioned as "the result of a combination
of tcp timestamps and header compression"?
Also, is there any standard way (e.g. pppconfig) to turn off tcp
timestamps other than "echo 0 >/proc/sys/net/ipv4/tcp_timestamps"? And,
how to turn off ppp header compression?
Please help us solve this annoying ppp problem.
Best regards,
Jonathan Chang
PS: I still have no chance to test your solution to this problem.
But I will report the result on the mailing-list later.
