BGP: Route-Target limit?

[melissaharper]

Is there a limit to the number of Route-targets you can have defined/configured under a Route Distinguisher in BGP?

[Harold Ritter · Accepted solution]

Hi Melissa,

There use to be a hard limit of 128 extended community in older IOS versions. There is no longer a hard limit but it is now derived from the maximum BGP message length (4096), which leads to a maximum of +/- 509 extended communities per update.

Regards

[melissaharper]

So in what IOS ver did this change, just curious?  How old is "older ios"?  Thank you.

[Harold Ritter]

Hi Melissa,

This happened a long time ago (~12.3T/12.4). It was implemented via CSCee30718.

Regards

[melissaharper]

Awesome!  Thanks so much for your reply and information.