BBN TCP/IP question

[Steven Kahn]

[]
We're trying to put BBN VAX TCP/IP sys. 10.16 up under 4.1BSD on
a VAX.  We're interfacing the VAX to an Ungermann-Bass broadband
network via a DR11-W parallel interface.  We have got FTP and
telnet working to a degree, but are having a few minor problems.
Specifically, after a little while the allocated message buffers
(mbuf's) get scribbled on and the machine crashes.

More detail:  We have tried this under a version of VMUNIX that
is as close to the distribution as our hardware allows, as well
as a heavily instrumented version of our current system with the
TCP/IP code.  It happens faster in the latter case (not sure why),
but eventually our instrumentation reports massive corruption in
the mbuf's, followed sooner or later by some program attempting
to indirect off a corrupted pointer.  (In the non-instrumented
version, this is verified by post-mortem autopsies.)  We have
even done a "local loopback" of our driver, so that virtually
none of our code is called: the same linked list of mbuf's that
gets passed to the UB send routine is returned by the UB receive
routine untouched.  To no avail.

If anybody has experienced this before or has any suggestions,
we would be very glad to hear from them.  If anyone has been
having unexplained crashes with BBN TCP/IP:  now you know ...

Steve Kahn, Johns Hopkins University Applied Physics Lab
...!seismo!umcp-cs!aplvax!milo!steve	or
aplvax!milo!steve at maryland

Joseph S. D. Yao, Hadron Inc. / JHU-APL
...!umcp-cs!aplvax!milo!jsdy	or	...!seismo!hadron!jsdy	or
aplvax!milo!jsdy at maryland	or	hadron!jsdy at seismo