show route l3out epg??

[Ibrahim010]

Hi Guys,

Is there a way in ACI I can find out which peg to use when it comes to l3outs? Like a show IP route.... For example, I have a host which belongs to epgX and it needs to connect to some destination on the internet or a network that sits behind an l3out. Now at my new workplace, we have a lot of EPGs and most the names don't make a lot of sense to me. We have an EPGinternet, EPGexternal, EPGetc.. and I often find myself having to ask colleagues which peg to use when it comes to l3outs. Is there a  way i can figure this out by myself via a command or gui? I hope my question makes abit of sense.

Thanks.

[Sergiu.Daniluk · Accepted solution]

Hi @Ibrahim010 

Not sure what you mean by "peg". Is it a typo? Do you mean "EPG"?

And by referring to L3Outs, I suppose your question which externalEPG you should look for, correct?

Now, there are a couple of things which you need to know:

- external EPG is not used for routing. The L3Out is doing that. So regardless if you have one or 10 extEPG in your L3Out, the routes will all be the same on the configured BorderLeafs

- external EPG is used for policy enforcement: applying contracts on it and selecting "external subnets for external EPG".

Now if we should rephrase the question: how do I know on which ExtEPG is an external subnet configured? then the answer is not very straight forward. I think the easiest way is to go on APIC and use "show external-l3 epg" command. Then look at the 'match' column for the prefix you are interested and you should find the ExtEPG you are interested.

There is another method on looking for prefixes on BL, then take the PCtag associated with it and go back to APIC, use moquery etc. Too troublesome and time consuming. 

Take care,

Sergiu

[Ibrahim010]

Hi Sergiu,

Apologies for the late reaction, I have been really busy and forgot all about the question posted here. Yes, I do mean epg, was writing it in a hurry so my bad there as well. Thanks for your reaction, I appreciate it! Your solution was really helpful. I also found the command moquery -c l3extSubnet | grep x.x.x.x which is what I needed seeing I use to have endpoint IP addresses but having a hard time finding the epg.

Thanks again.