Re: Load Balancing over several interfaces

From: Jon Zeeff <>
Date: Fri, 16 Oct 1998 09:18:07 -0400 (EDT)

> >> route add default main_gateway
> >> route add net mask secondary_gateway
> >
> >Remember that this only balances outbound traffic. Inbound still comes
> >whatever route the external routing tables (usually BGP4-entries) define.
> >And the outbound traffic is the least of the problems on a proxy server.

As you and others pointed out, with two interfaces with different ips, it
does balance both. Also, in the case of a transparent accelerator,
outbound traffic is the bulk of the traffic and what matters most.

More importantly, this time based method of switching back and forth
is a bad idea. Since most tcp stacks don't lock the session to one
interface, outgoing will just alternate between links (vs. being balanced).
TCP will not function as well with the rapid changes in rtt.

I'd either use the route table (easy) or hack squid to pick a source
ip address based on interface load (more dynamic).
Received on Fri Oct 16 1998 - 07:27:54 MDT

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