Aggregate-address and aggregate-address summary-only

[InternetB]

Hi,

I would like to know what is the difference on the usage of the commands, aggregate-address and aggregate-address summary command.

What I understand that the usage of both the commands work only if there is a longer prefix in the RIB. Using the summary-only keyword supresses the longer prefix but isnt't the aggregate-address command do the same as well ?

Thank you,

Regards,

InternetB.

[Richard Burts]

InternetB

Both commands look for any longer prefixes that fall into the range defined in the aggregate address command and if they find prefixes then they generate the aggregate address to advertise. The aggregate-address command advertises both the summary and the more detailed routes while the aggregate-address summary-only advertises only the summary address and not the more detailed routes.

HTH

Rick

[InternetB]

Rick,

Well if the aggregate-commands advertises the detailed routes and the summary route, what is the point of aggregating it in the first place ? I mean what is the benefit of doing this ?

Thank you,

InternetB.

[Richard Burts]

InternetB

I do not have an authoritative answer for this. But I believe that the difference is to accommodate some circumstances where you want to advertise only the summary (to some peers) and want to advertise the summary and supporting more specific routes (to some other peers).

HTH

Rick