[c-nsp] Load Balancing T1s on 2611

[Oliver Boehmer (oboehmer)]

Pete Templin <> wrote on Sunday, July 24, 2005 2:22 PM:

> Roger Weeks wrote:
> [snip]
>> Here's what I've done:
>> 
>> ip cef
>> ip load-sharing per-packet (on the serial interfaces)
>> 
>> dual ip route 0.0.0.0 0.0.0.0 upstream router entries
>> 
>> This is all we've done before to get load sharing working.  However,
>> looking at the bandwidth utilization on the T1s, the old T1 is taking
>> all the load except for about 20-40k on average on the new T1.
> 
> Are the ip route entries pointing to IP addresses or interfaces?  I've
> found that if they point to addresses, load-sharing does not occur
> (which can be verified with "sh ip route 0.0.0.0" where only one route
> is visible).

But CEF will still recurse to both links if this ip address is resolved
via both links, i.e.

ip route 10.0.0.0 255.255.255.0 2.2.2.2
ip route 2.2.2.2 255.255.255.255 Serial0
ip route 2.2.2.2 255.255.255.255 Serial1

will still use both links (I think CEF recurses several steps down, so
this will work as well:

ip route 10.0.0.0 255.255.255.0 2.2.2.2
ip route 2.2.2.2 255.255.255.255 3.3.3.3
ip route 3.3.3.3 255.255.255.255 4.4.4.4
ip route 4.4.4.4 255.255.255.255 Serial0
ip route 4.4.4.4 255.255.255.255 Serial1

	oli