Hello,
I have a simple 3 AS BGP Confederations - 1,2 and 3. All belong to the outer AS '10'.
AS1 <---> AS2 <---> AS3
Announcements from AS1 to AS2 and vis-versa are fine.
Announcements from AS2 to AS3 and vis-versa are fine as well.
However, from AS3, I would like to see the routes announced to AS2 from AS1, re-announced. Meaning, I want to get to AS1 routes through the BGP path.
The "redestribute Other BGP" seems to be for other instances - as I only have one.
I also tried "ignore AS path" and that didn't help either.
Do I need to create some prefix lists of some sort?
Thanks in advance.
Solution? BGP Confederation - far-ends announcements not be
I believe I figured it out and I have the each other's far-end routes being announced through.
Here is what I did ... not 100% sure if this is the correct way, so please comment.
On AS2s edge router, which is the glue between the two peering ASs, I created an aggregate item with a summary of the subnet of AS1 and listed it as "BGP-OUT-FROM-AS1".
I then when to the BGP peer item for AS3, and put in as the outfilter the "BGP-OUT-FROM-AS1".
Whol -la .. AS1's routes are now showing up in the received routes on the AS3 edge router.
Lastly, I reversed the above for the traffic to get back the new path by creating a BGP-OUT-FROM-AS3 and applying that to the peer facing AS1.
Again, I am not 100% if this is the best way to handle this. Thoughts? Comments?
Thanks,
Here is what I did ... not 100% sure if this is the correct way, so please comment.
On AS2s edge router, which is the glue between the two peering ASs, I created an aggregate item with a summary of the subnet of AS1 and listed it as "BGP-OUT-FROM-AS1".
I then when to the BGP peer item for AS3, and put in as the outfilter the "BGP-OUT-FROM-AS1".
Whol -la .. AS1's routes are now showing up in the received routes on the AS3 edge router.
Lastly, I reversed the above for the traffic to get back the new path by creating a BGP-OUT-FROM-AS3 and applying that to the peer facing AS1.
Again, I am not 100% if this is the best way to handle this. Thoughts? Comments?
Thanks,
Re: BGP Confederation - far-ends announcements not being see
Code:Select all
AS 1 /routing bgp instance set 0 confederation-peers=2,3 AS 2 /routing bgp instance set 0 confederation-peers=1,3 etc…Re: BGP Confederation - far-ends announcements not being see
Thanks for the reply Blake. AS1 isn't directly connected to AS3, so that will work? I obviously have this set on the instance on AS2 as it's the "man in the middle" - but didn't think do to this on AS1 or AS3 since they are not direct talkers.Code:Select allAS 1 /routing bgp instance set 0 confederation-peers=2,3 AS 2 /routing bgp instance set 0 confederation-peers=1,3 etc…
Re: BGP Confederation - far-ends announcements not being see
You're right, its only needed on AS2.
Can you post your BGP peer and filter configs?
Can you post your BGP peer and filter configs?
Re: BGP Confederation - far-ends announcements not being see
Sorry for the delayed reply. Here is my config on the inter-connected AS2 router.
Let me preface that again, I am not sure if this is the best way to accomplish this. I take it that there is probably several ways to solve this ...
Let me preface that again, I am not sure if this is the best way to accomplish this. I take it that there is probably several ways to solve this ...
Code:Select all
add address-families=ip as-override=no default-originate=never disabled=no hold-time=3m in-filter="" instance=default multihop=no name=\ ibr1.gpt1 nexthop-choice=default out-filter=BGP-OUT-1 passive=no remote-address=172.29.0.2 remote-as=1 remove-private-as=no \ route-reflect=no tcp-md5-key="" ttl=default update-source=172.29.0.1 use-bfd=no add address-families=ip as-override=no default-originate=never disabled=no hold-time=3m in-filter="" instance=default multihop=no name=\ ibr1.mob2 nexthop-choice=default out-filter=BGP-OUT-3 passive=no remote-address=172.29.0.6 remote-as=3 remove-private-as=no \ route-reflect=no tcp-md5-key="" ttl=default update-source=172.29.0.5 use-bfd=no
Code:Select all
add advertise-filter=BGP-OUT-3 attribute-filter="" disabled=no include-igp=no inherit-attributes=yes instance=default prefix=\ subnet.from.as1.0/24 summary-only=yes suppress-filter="" add advertise-filter=BGP-OUT-1 attribute-filter="" disabled=no include-igp=no inherit-attributes=yes instance=default prefix=\ subnet.from.as3.0/24 summary-only=yes suppress-filter=""Who is online
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