Redundant transit ISP design

[nikolay-shopik]

We are small transit ISP for other downlinks. And currently have such setup 7201 and 7206NPE-G1, as core and edge routers also we have connected to IXP. Downlinks usually BGP connected to one of border router which is terminated via VLAN, thus sub interface. IXP are also connected via VLAN on router.

What I don't like about this is when one borderd goes down downlink will lose connectivty, also recently we start growing and getting more downlinks, so balancing between borders become problem. So my question is, what you guys sugget to make setup less fragile and more redudant.

Thanks

[esomarriba]

I would start making my network design more best practice, Use the CDA (Core, Distribution, Access) layers. I would add a 3rd router only for the IXP peering, and secure my BGP/prefix-list.

[nikolay-shopik]

There barely need for 3 layer network design, maxium is two with core/aggregation and access layers.

[samavedula_rama]

I would say replace the switch that connects to the 2 7200's with a high-end one, like a Cisco Catalyst or something and do BGP with downlinks there, instead of doing BGP at 7200s. This will give you control over the routes you advertise to the 2 uplinks and also the IXP.

I would still say that there would be a single point of failure but alteast frees you from UPLINK issues.

This is just a randomn thought and if I get any more ideas, I will let you know.

[nikolay-shopik]

Yeah I was thinking about same, minum what I can install here is Cisco ME 3600X because it has lots of memory so can handle bgp full view.