networking bug?

[Chris Torek]

>In article <742 at rosevax.Rosemount.COM> dave at rosevax.Rosemount.COM
(Dave Marquardt) writes:
>>I've got a problem.  We have a VAX-11/785 running 4.2BSD, and every
>>two weeks or so, telnet and rlogin stop working. ... In checking out
>>the problem, I tried using telnet from the VAX to another machine,
>>and got this message: Out of buffer space.

In article <235 at rust.dec.com>, sweeney at rust.dec.com (Glenn Sweeney) writes:
>This problem exists because the system is failing to properly release
>mbufs after they are used.

I doubt this:  A stock 4.2BSD system will panic with `panic: exit:
m_getclr' very soon after running out of mbufs.  There is at least
one other place in a 4.2 kernel that generates `ENOBUFS' errors,
and that is in the PSN (nee IMP) code in /sys/netimp.

The workaround (increasing NMBCLUSTERS) may still be useful on a
very busy system, where it is indeed possible to run out of space
(and soon panic).  But if you have a connection to a PSN, see if
perhaps your routing tables have become confused.  `netstat -r'
prints the kernel's routing tables.

(Better yet, convert to 4.3BSD and fix all those lurking bugs at
once.  It seems significant that only a handful of fixes have been
posted for 4.3BSD since its release, whereas 4.2 generated a
veritable flood. . . .)
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690)
UUCP:	seismo!mimsy!chris	ARPA/CSNet:	chris at mimsy.umd.edu