From: Fco.J.Ballesteros <nemo@plan9.escet.urjc.es>
To: 9fans@cse.psu.edu
Subject: [9fans] IP_DF bit and broken connections
Date: Tue, 3 Dec 2002 14:09:47 +0100 [thread overview]
Message-ID: <bd6954a17427f079cf673f2fa9a75f63@plan9.escet.urjc.es> (raw)
Hi,
we've found that if we dont disable the check for IP_DF bit while
processing a fragment in ip.c, then some of our connections break from
time to time. By doing this change, everything seems to work fine for
us:
diff /n/dump/2002/1203/sys/src/9/ip/ip.c /sys/src/9/ip/ip.c
315c315
< if(eh->frag[0] & (IP_DF>>8)){
---
> if(0 && eh->frag[0] & (IP_DF>>8)){
The reason seems to be that some times when we connect through our
router, we get packet fragments which also carry the DF bit set.
Since we're not network gurus, we asked to our local network
programming guru and he suggested not to even look into the DF bit if
we're not gatewaying.
I don't think this is a `Plan 9 problem', but since it did forbid
us to keep our connections alive when going through some routers, I
thought it could be of help for others.
We'll continue tracing this problem. In case we find out anything,
we'll let you know.
next reply other threads:[~2002-12-03 13:09 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-12-03 13:09 Fco.J.Ballesteros [this message]
2002-12-03 14:16 presotto
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