According to Ignatios Souvatzis:
>
>Thats not pppd that gets blocked. Thats your modem -- tty device -- connection
>that fails to transmit the "hangup" signal.
>

Sorry, no.  I am not sure what it is but I can make my ppp link stop
just by remote displaying emacs over the link, the modem definitely
stays off-hook so the line does not go away underneath me and this
happens if I have dialled into a Cisco modem server or in via an annex
terminal server (don't care what other people say the annex has worked
well for me for _years_).  I too have found that a constant ping, or
just about any dribble of traffic seems to help keep things going for
longer but the link will still, eventually, lock up.

  The behaviour seems to be related to the link usage.  I normally
forward X over ssh to get compression & security.  I sometimes have
had to forward the FW-1 management tool display across my ppp link,
this works fine BUT if I try to forward emacs over the same link it is
pretty much guaranteed the link will lock up before I have finished an
email reply - and, yes, it is the link locked up because pings fail
and my other sessions are dead in the water.

-- 
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Brett Lymn, Computer Systems Administrator, BAE SYSTEMS
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