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Cisco FTD - BGP two instance (two different AS Number)

mikiNet
Level 5
Level 5

Dear Team,

I have a problem related to BGP configuration. I have below topology:

mikiNet_1-1770370545472.png

I want to run two BGP instance (two AS number on FTD):

1. BGP AS 49001, where FTD will establish iBGP with upper router

2. BGP AS 65001, where FTD will establish eBGP with down router (his AS 65002)

But I don't see any possiblity to run two BGP on FTD. On General Setting I have only option to put ONE AS Number...

Also when I create VRF, I still option to use ONE AS..

Is it possible to run two AS on same FTD ? 

2 Accepted Solutions

Accepted Solutions

M02@rt37
VIP
VIP

Hello @mikiNet 

ASN with network equipment ? Firewall_routers => Only one AS possible ! You cannot run multiple local ASNs as the same time in one BGP process. Some network equipment permit with the command "local-as" to established bgp session with neighbor with a "fake" asn...

 

Best regards
.ı|ı.ı|ı. If This Helps, Please Rate .ı|ı.ı|ı.

View solution in original post

Cristian Matei
VIP Alumni
VIP Alumni

Hi,

@mikiNet Don't overcomplicate it using a VRF / separate Virtual Router. Recommend to run BGP in AS 49001 too establish iBGP upstream and for eBGP peering downstream use local-as functionality when configuring the eBGP neighbor (found under Migration tab). To ensure you can advertise BGP best-paths between your eBGP and iBGP neighbors, and these will not reject the updates due to AS loop prevention, when using local-as functionality, ensure to check minimum the first two knobs as well (Do not prepend local AS, Replace Real AS).

Thanks,

Cristian.

View solution in original post

2 Replies 2

M02@rt37
VIP
VIP

Hello @mikiNet 

ASN with network equipment ? Firewall_routers => Only one AS possible ! You cannot run multiple local ASNs as the same time in one BGP process. Some network equipment permit with the command "local-as" to established bgp session with neighbor with a "fake" asn...

 

Best regards
.ı|ı.ı|ı. If This Helps, Please Rate .ı|ı.ı|ı.

Cristian Matei
VIP Alumni
VIP Alumni

Hi,

@mikiNet Don't overcomplicate it using a VRF / separate Virtual Router. Recommend to run BGP in AS 49001 too establish iBGP upstream and for eBGP peering downstream use local-as functionality when configuring the eBGP neighbor (found under Migration tab). To ensure you can advertise BGP best-paths between your eBGP and iBGP neighbors, and these will not reject the updates due to AS loop prevention, when using local-as functionality, ensure to check minimum the first two knobs as well (Do not prepend local AS, Replace Real AS).

Thanks,

Cristian.

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