From: Buckner, Edward (ebuckner@xxxxxxxxxxxxxxxxx)
Date: Tue Nov 14 2000 - 23:00:30 GMT-3
Title: Anybody will to change lab dates in Halifax
I have a lab date for Halifax on the 11-16 60 11-17 if anybody would
like to trade just give me a reply by 11/15. I'm currently stuck on an
assignment in San Jose and can't break away.
Edward Buckner
Email: ebucknerneteffectcorp.com
-----Original Message-----
From: Jennifer Joy [mailto:jjoy@tri.sbc.com]
Sent: Tuesday, November 14, 2000 5:07 PM
To: ccielab@groupstudy.com
Subject: bootcamp lab 8, ospf<->bgp questions
Well, I've been bugging all my friends so much for help, I thought
I'd better give them a break. I'm working on the OSPF <-> BGP
part of lab8. I finally went to the answers to try and figure it
all out. I would appreciate some inline comments.
In this bootcamp lab you are supposed to get all of OSPF into BGP
and vice-versa. Don't read further unless you want to see some
snippets of answers.
r6 is an EBGP peer with r8
r1 is an EBGP peer with r7
r6 and r1 are IBGP peers
r8---r6--------r1--r7
In the solutions they do this...
r1 and r6 have:
router ospf 7
redistribute connected metric 20 subnets route-map FILTER-LOOP
redistribute bgp 2 metric 20 subnets
where FILTER-LOOP adds *only* the WAN link between EBGP peers
route-map FILTER-LOOP permit 10
match ip add (WAN)
Now the WAN link is the only network being advertised via the
EBGP peer. So why the route-map? I am not sure. Is that to
make sure the route is there so we can run without "no sync"?
Also, since there is no following route-map statement, is that
taken to be an explicit deny?
Now going from BGP -> OSPF more filters:
router bgp 2
redistribute ospf 7 route-map FILTER-EX-OSPF-FROM-BGP
now looking at that name, you'd think that means remove external
OSPF routes from BGP.
the route-map looks like this (minus some later requirements):
route-map FILTER-EX-OSPF-FROM-BGP permit 10
match route-type internal
route-map FILTER-EX-OSPF-FROM-BGP deny 20
match ip add {routes from other EBGP peer}
route-map FILTER-EX-OSPF-FROM-BGP permit 30
match route-type external
Now, if as another poster said, OSPF by default adds internal,
why do we have to add it here?
Why on R1 do we filter R8's EBGP routes and vice-versa?
It doesn't seem like we have filtered any external OSPF routes.
Does anyone have some general tips on going between OSPF<->BGP
or can explain this exercise.
Thanks,
Jennifer
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 08:25:45 GMT-3