Network running only BGP internal/external???

BroadcastStorm

Hey guys, I need some opinion on a network running solely on BGP having just 2 office 1 branch and one corporate, what are repercussion of just having BGP as our internal/external routing protocol, the admin at work manually encodes routes on the linux/windows box, so I was asked by our director to create a report, which is below, I would highly appreciate network gurus feedback on this matter since I am only CCNA level and just currently working on my CCNP

This is the draft I am writing for our Director.


Our corporate network is using static routing they are manually encoded, we currently do not have an internal routing process such as RIP version 2 or OSPF (which I highly encourage that we should, we can't use EIGRP because we are multi-vendor Cisco/Foundry).

BGP is used for routing between two or more autonomous systems meaning 2 networks with 2 different domains that are running controlling the routes using different internal routing protocol such as IGP/RIP v1 & 2/OSPF/EIGRP (there are more to name), with the size of our company I highly believe 1 autonomous system is sufficient, BGP has different uses such as having it carry OSPF routing table to a different BGP network due to different administrative controls such us publishing routes to ISP etc.,

In our case we control our Distribution Center as well as Corporate office.

What I suggest is to get the internal routing straighten out, our MPLS is a site-to-site and anything we publish on our internal routing gets published through each other in our case Corporate and Distribution Center, once we become expert with our network and our internal routing it will become clear on how we can leverage BGP, right now I think it's overkill.

So to conclude our internal routing should be straighten out thoroughly throughout our offices, then we can really hash out what function BGP is going to serve us, I should have more informations since I am researching BGP implementation.

deth1k

You still need an IGP for iBGP connectivity unless you want to rely on static routing. I can understand you are using providers MPLS network for site to site VPN is this correct? Are you using eBGP as PE-CE routing protocol?
Do you have any backdoor links between the sites? Are those being used for backup connectivity?

JTAlberts

BroadcastStorm wrote: »

Hey guys, I need some opinion on a network running solely on BGP having just 2 office 1 branch and one corporate, what are repercussion of just having BGP as our internal/external routing protocol, the admin at work manually encodes routes on the linux/windows box, so I was asked by our director to create a report, which is below, I would highly appreciate network gurus feedback on this matter since I am only CCNA level and just currently working on my CCNP

This is the draft I am writing for our Director.


Our corporate network is using static routing they are manually encoded, we currently do not have an internal routing process such as RIP version 2 or OSPF (which I highly encourage that we should, we can't use EIGRP because we are multi-vendor Cisco/Foundry).

BGP is used for routing between two or more autonomous systems meaning 2 networks with 2 different domains that are running controlling the routes using different internal routing protocol such as IGP/RIP v1 & 2/OSPF/EIGRP (there are more to name), with the size of our company I highly believe 1 autonomous system is sufficient, BGP has different uses such as having it carry OSPF routing table to a different BGP network due to different administrative controls such us publishing routes to ISP etc.,

In our case we control our Distribution Center as well as Corporate office.

What I suggest is to get the internal routing straighten out, our MPLS is a site-to-site and anything we publish on our internal routing gets published through each other in our case Corporate and Distribution Center, once we become expert with our network and our internal routing it will become clear on how we can leverage BGP, right now I think it's overkill.

So to conclude our internal routing should be straighten out thoroughly throughout our offices, then we can really hash out what function BGP is going to serve us, I should have more informations since I am researching BGP implementation.

What type of LAN do you have at each sites? Is you WAN router acting as the router for all your local networks? Do you have more than 1 router at each of the sites? My current network is a global network and we run nothing other than eBGP.

fonque

On our network we run different routing domains for each service, and use bgp to tie them all together. for example, our wireless network is one domain, the wired LAN is second domain, our data center is another domain etc..

yebo2010

My understanding is that you are running a relatively small sized LAN(having just 2 office 1 branch and one corporate). Having one domain is fine. For BGP, I would recommend the following: If you have several connections to the internet(say > 2 ISPs) then yes you need it. And because BGP(iBGP) requires direct connectivity among the routers(mesh, which is not a good idea) or connectivity using an IGP, I would recommend using OSPF as an IGP.

If you are not multi-homming then the idea of iBGP is not ideal. OSPF alone can work fine. Just have a static route the ISP.

But more advice can be given if you provide the total number of users, number of routers and switches(and their capabilities), or simply put a network diagram showing logical connections of devices.