On Jul 18, 11:14 am, Digital Mercenary For Honor
wrote:
> On 2008-07-12 10:32:43 -0400, Tom Lobato said:
>
> > I searched for some linux distro with this feature (good failover)
> > bult-in, but didnt found anything interesting.
>
> What failure cases, specifically, are you looking to address? I'm
> curious, and based on that, I might be able to toss in $0.02 cents on
> where to rummage.
>
> /dmfh

hello dhfh!
I`m doing multihoming with linux. Lartc gave me how to do load
balancing, with

default proto static
nexthop via X.X.X.X dev eth1 weight 1
nexthop via Y.Y.Y.Y dev eth2 weight 1

but a good feature would be failover, when one of the links goes down,
the system detects it and removes it from the routes.

I`m doing failover with ping. I`m pinging external hosts periodically
and if ping response does not come back, it judges the link is bad
(actually,
it makes some retries, taking about 4-5 minutes before removes the bad
route).

The problem:
When network load is too high (upload and/or download) ping responses
takes
6, 9, 12 seconds to come back, and sometimes never comes back. So the
tester thinks erroneously the link is bad and removes route to ISP.

I`m searching best practices or cases for improve the tester so it can
make
more reliable tests.

Well, I`m doing my homework, trying to use shaping and policy to
priorize ICMP
traffic to "own the queue" (http://lartc.org/howto/
lartc.qdisc.html#LARTC.QDISC.EXPLAIN).
But would be nice to hear experiences and best practices.


Tom Lobato