From: Gregg Malcolm (greggm@xxxxxxxxxxxxx)
Date: Tue Apr 02 2002 - 15:48:51 GMT-3
Folks,
I'm having trouble with the following scenario. I set it up with the purpose
of playing with routing loops.
______ E0 - 150.50.30.2/27
|
R2
/ \
/ \
/ \
R5 R6
| |
| |
---------------------
|
R7
R2, R5 and R6 are on multipoint frame cloud. They run RIP in the address
range 150.50.100.0/27.
R5, R6 and R7 are on Ethernet. They run ospf in the address range
150.50.7.0/25
R5 and R6 do mutual redist of RIP/OSPF.
I have added a distribute-list on R5 and R6 that denies the 150.50.30 route
from re-entering OSPF via the Ethernet. Prior to that (as you can imagine),
OSPF's lower admin dist caused R5 and R6 to see the subnet as OSPF. I've
also prevented RIP from re-advertising the .30 subnet from OSPF. (I think :))
Problem is, when I do a trace from R7 to the .30 subnet, I get sub-optimal
routing where it bounces from R6 to R5 back to R6 and then to .30. Both R5
and R6 show the .30 route as RIP with a next hop of R2. I've played around
with DR selection thinking that might be the problem, but no change.
FLSM/VLSM issues have been addressed. R2 has 2 routes to the R5,R6,R7
Ethernet and R7 has 2 routes to the .30 subnet.
I'm fairly certain that I could remedy this with policy routing, but I'd
rather not. I'd like to know why. Any ideas ? This one is kickin my butt.
Sorry if the ASCII art format is screwed up.
Thanks, Gregg
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:57:52 GMT-3