3850 and BGP

[rrfield]

This is a fairly general question, but I have a stack of two 3850 switches with the IP Services IOS (or whatever its called now in IOS 15, it's the license that removes EIGRP stub) for a new deployment with Two ISP's.  Both ISP's will hand us an Ethernet port, and we will peer with each ISP with BGP to advertise our address space (a single /22).  We will receive a default route from one ISP, and a default route and the ISP's local routes from the other.

We originally planned to use two 2921 routers to peer with the ISP's, but I'm not sure thats necessary.  Does BGP work pretty well on the 3850's in others experiences?

[Leo Laohoo]

Catalyst switches do NOT do NAT.  So are you expecting your switches to do NAT-ing?  

What WAN speed are you expected to have?

I've never seen someone run BGP on a production 3650/3850 and one of the most important factors to consider is the full BGP table and the amount of DRAM on the appliance.

[rrfield]

 No NAT.  As I stated above, we are only getting default routes and maybe one ISP's local routes, so the routing table size won't be an issue.  If it does, I'll just accept default routes and that will be that.

All BGP features we currently use appear to be supported by the 3850, or at least it accepted the commands.  Our config isn't anything special.  Just curious about peoples impressions of BGP on the 3850's.

thanks!

[rrfield]

Oh, forgot to add...

One ISP will provide a 100mb connection (ethernet handoff), and the other will be 60mb (also ethernet handoff).

[Reza Sharifi]

3850 should be able to handle both with no issues. I use on old 3560G with 100mb connection to Internet and it is fine.

HTH

[jerry.grubbs11]

Reza;

Forgive me for bringing this up again, but I am wanting to use 3850's for a BGP connection to level 3 and only have them deliver a default route and then advertise about 10 routes. How did the use of your 3850's for BGP work? Thank you.

[rrfield]

The IOS we were running at the time had a lot of bugs and we were pulling our hair out for a few days until we went back to Plan A and used the 2921 routers.  We've since upgraded the IOS and all is stable, and we are actually using iBGP and EIGRP on the 3850 stack with no issues.

I forget the version of IOS we were running, but it became known as Devil's Code in our organization.

[Reza Sharifi · Accepted solution]

As long a you are only getting a default route from the providers and not full routing table, the 3850 should work just fine. And as Leo said no NAT unless you have a device sitting behind the router (e.g a firewall) that will do NAT for you.

HTH

[rrfield]

Great, I'll give it a shot!  Thanks.