SEO

On Tue, Feb 26, 2008 at 04:39:02PM +0000, Stuart Henderson wrote:
> More specifically: when this happens,
>
> - frames transmitted by the 5501's vr(4) are correctly received
> at the other end of the wire.
>
> - frames sent to the 5501 do not appear in tcpdump -i vr0.
>
> I think I've seen, *one* time, that moving the cable from a laptop
> to a switch (i.e. changing between MDIX and MDI) made it work again
> without down+up, but I can't now replicate that. (This is vt6105m
> which has auto mdi/x).

I will happily try to test anything related to this issue,
just let me know.

I sometimes have to down/up a vr interface in my 5501 to get it to reply
to dhcp requests as well. When this happens it's as if the bridge suddenly
decided to stop learning about MAC addresses appearing on an if_vr interface.
The MAC address of the box issuing DHCP requests does not show up in the
bridge's MAC address list, even after waiting for a few minutes.
The problem does not happen often, and I cannot reproduce it reliably.
It's usually confined to a only one port (i.e. one if_vr interface).
I've tested plugging the box issuing DHCP requests into a different
port when the problem happened, and the bridge picked it up immediately
and the DHCP request succeeded.

All vr interfaces are in a single if_bridge. I haven't yet tried to
put another switch in between.

Besides, I also have a tun interface in the bridge (in tap mode).
I use this together with openvpn to get an ethernet interface in my lan
from remote. A possibly unrelated problem is IPv6 neighbour discovery on
the tun interface: neighbour discovery packets seem to be dropped silently
(but not by pf). It does work between the vr interfaces though. Still very
annoying - I have to hard code MAC addresses into the ndp cache on both
sides of the VPN link to make IPv6 work through the VPN. IPv4 works fine.
I can reproduce this problem reliably, but I guess it's related to
if_bridge or if_tun rather than to if_vr.

--
stefan
http://stsp.name PGP Key: 0xF59D25F0

[demime 1.01d removed an attachment of type application/pgp-signature]