(KAME-snap 8803) Re: Weird memory exhaustion with FreeBSD 4.10-STABLE

[JINMEI Tatuya /神明達哉]

>>>>> On Mon, 27 Sep 2004 07:57:02 +0300 (EEST), 
>>>>> Pekka Savola <pekkas at netcore.fi> said:

>> I can think of several possibilities that may cause the entries:
>> 
>> - when this node sends ICMPv6 error messages to those addresses, it
>> can create route entries.  I suspect this is the main reason since
>> in this case the destination of route entries would contain other
>> types of addresses than 6to4.  You can (implicitly) check if this
>> happened by looking at the result of 'netstat -s -p icmp6'

> This is likely the case.  Due to Microsoft's implementation of '6to4 
> relay probing', each host tries to send an IPv6 packet of Hop Count=1, 
> which results in an ICMP unreachable back from the relays.  See below.

Okay.  Now I think I figure out the problem.  Those host routes were
created not deliberately, so the kernel will eventually need a fix to
this.

But if you are in a hurry and/or cannot replace the kernel soon, I
think setting net.inet6.ip6.rtexpire to 0 can be a workaround (with
this you even do not have to reboot the kernel - though rebooting may
also help if you can).

					JINMEI, Tatuya
					Communication Platform Lab.
					Corporate R&D Center, Toshiba Corp.
					jinmei at isl.rdc.toshiba.co.jp