tech-net archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: IPv6 forwarding fail = mbuf leak?

Mouse <mouse%Rodents-Montreal.ORG@localhost> writes:

>> What is the interface type on the upstream link?
> As seen by the host, Ethernet.  The physical layer is DSL (MVL, to be
> specific), but as far as I've been able to tell it's operationally just
> a really slow Ethernet.  (In case it matters, the DSL CPE is behind a
> switch which vlan-trunks that, among other things, to the router host.)
> The other end is not a mass-market big-ISP head; the DSL is being run
> over dry copper to a DSLAM at my upstream/employer.

Wow, how unusual.


  What driver (wm? fxp? vr?) is in use?

  Is the underlying physical interface the same one for the DSl-facing
  vlan as the house-lan-facing vlan?

> Native, or at least as native as IPv6-over-Ethernet ever is.  (Not
> counting comments, there's nothing in the network config that says
> vlan4 is a DSL line instead of a normal Ethernet.)

OK, that's what I meant by native.

>> Static route, or some IGP, or BGP, or ?
> Entirely manually-configured statics.

So this should be easy to reproduce.  I do wonder if it has to do with

>> When you said "isn't answering", do you mean that you have an ndp
>> cache entry, but when the unicast packet is sent, there is no
>> link-level receiver?  Or do you mean that there is no ndp entry,
>> because it doesn't answer the ndp request packets?
> The latter.  (It might have been the former initially, but certainly
> after the reboot to clear the first wedge it will have been the latter
> until I fixed things.  The upstream host and my router disagreed over
> what /127 to use on the DSL; I must have changed one end but not the
> other and not rebooted since, or some such.)

I dimly remember that ARP used to store a packet when sending an arp
request, so that it could send it when the reply came.  But that
requires freeing the old one (with a queue of 1).  I am unclear on how
NDP does this, but it's something else to check.

Attachment: pgpNEDZSXHFMl.pgp
Description: PGP signature

Home | Main Index | Thread Index | Old Index