Re: kerneld/multicast bug (tickled by gated)
Sun, 15 Jun 1997 12:21:44 -0400 (EDT)


It's not clear that we want to disable pppd in that way
for general use with gated. Perhaps, if I mentioned that
the specific call is related to the IP multicast additions
it would help. Also, when we disabled kerneld (i'm not sure of
the terminology here.. so please pardon my newbie language)..
the hangs stopped.

Does the linux kernel handle multicast groups being set across
ppp links? Thank-you for your quick response.

Sue Hares
Gated maintainer
and linux newbie

>> In running gated on this network, we have discovered a Linux kernel/kerneld
>> bug, and I wonder if anyone on this list might be able to shed some light on
>> it (or even propose a fix)
>> The symptoms are as follows:
>> 1. gated sometimes hangs.
>> 2. When it is in the hung state, it can still be made to dump core
>> ('gdc COREDUMP'), and gdb shows that it was waiting in setsockopt() for
>> an IP_ADD_MEMBERSHIP request.
>> 3. At the same time as gated hangs, an extra process is in the kernel table:
>> request-route <zombie>
>> which is a child of kerneld
>The request-route script distributed with the modutils package starts pppd
>when a request is made for a connection to an IP address to which no route
>has been established. This way, one's ISP can be automatically dialed
>when one runs a program that uses TCP/IP.

>My limited understanding of gated is that it's a routing daemon similar to
>routed. It seems that while it's manipulating the routing table,
>something (perhaps gated itself) is trying to make connections through
>routes that don't exist. I assume you don't want to run pppd, so maybe
>just removing everything but "#!/bin/sh" from the request-route script
>would cause it to return, so gated can continue.