BGP connection to 32bit ASN

Unanswered Question
Jan 20th, 2009
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in order to configure peering between 16bit ASN and 32bit ASN - what is the requrement?

Would this be the correct configuration?

router bgp 45678

neighbor 1xx.0.0.2 remote-as 3.3

What software supports this configuration? (for C7600, RSP720)

According to Jeff Doyle we would need 12.2SRD, correct?


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Overall Rating: 5 (2 ratings)
Harold Ritter Tue, 01/20/2009 - 09:07
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The 2 byte ASN IOS can't be configured for 4 byte ASN. It sees its 4 byte ASN neighbor as 23456 (reserved ASN for migration purposes).

router bgp 45678

neighbor 1xx.0.0.2 remote-as 23456

For availability of the 4 byte ASN on the 7600, please contact you account team.


jon.harald.bovr... Wed, 01/21/2009 - 04:24
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Found IOS for 7200 to test customer CE as 32bit ASN (12.0.32S12).

Connected to old 16bit ASN.

Successful testing!

RIPE now assignes 32bit ASN. I would assume there to pop up some more prefix with as-path 23456 in few days.

Our customer will use Juniper as CE and are soon to be connected using 32bitASN.


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