On Sat, Sep 01, 2007 at 02:31:47AM +0200, Herbert Poetzl wrote:
> well, most likely, spanning tree is the magic word here :)
>
> (http://en.wikipedia.org/wiki/Spanning_tree_protocol)
I use spanning tree since my firewalls are redundant (STP
disables one firewall, which gives you a poor man's
failover capacity -- sure no carp+pfsync).
However, in this case the outages are intermittant, and what
happens is every couple hours or so the switch suddenly notices
a packet with a MAC which used to be on port 6 suddenly comes
in at port 49, at which point it ignores anything with that
MAC on port 6 until the period of MAC aging expires, and it
decides it's been port 6 after all.
So why would
switch-1 (level 3)
| |
NIC1 |
system |
NIC2 |
| |
switch-2 (level 2)
do that? Notice that the system doesn't route. It all
happens at Ethernet frame level.
-- Eugen* Leitl leitl http://leitl.org ______________________________________________________________ ICBM: 48.07100, 11.36820 http://www.ativel.com http://postbiota.org 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BEReceived on Sat Sep 1 10:37:57 2007