MPLS-TE BGP/OSPF

mike_perry · ‎04-17-2008

I am currently building mocking up our new WAN solution. Currently I am running MPLS with BGP as routing protocol, EIGRP peering to CE. The network is a collapsed PE/P which has three sites. I want to enable MPLS-TE to gain better control of bandwidth but unsure if I have to completely shut down BGP to run OSPF or if I have to run OSPF in parallel. If I run OSPF in parallel do I have to create an OSPF process for each VRF created under BGP. Help.

mheusing · ‎04-17-2008

Hi Mike,

As far as I understand you built a MPLS L3VPN solution with EIGRP as PE-CE protocol.

To setup internal MP-BGP peerings between PE routers you have an IGP (OSPF?) for loopback reachability, right?

MPLS TE will be enabled in the core IGP (OSPF?), which means it is completely transparent to CE routers. That said, you do not need to change any VRF related configuration.

You also do not need to shutdown BGP at all. MP-BGP is needed to exchange VPN-IPv4 routes between the PE routers. Removing BGP will break all VRF to VRF connectivity.

I am not quite clear about what you mean with "I want to enable MPLS-TE to gain better control of bandwidth".

MPLS TE in MPLS L3VPN environments is usually used to control traffic flow between PE routers. It is - simplified - a controlable way of routing traffic in an MPLS core. MPLS TE alone will not guarantee any bandwidth to any customer. QoS is needed to achieve this.

MPLS TE has some considerable complexity to setup and trouble shoot. So I would not recommend to place this technology in a core without deeper understanding.

To get a better understanding of the configuration tasks and possibilities please have a look at the MPLS Configuration Guide, namely at the section "How MPLS Traffic Engineering Works"

http://www.cisco.com/en/US/docs/ios/12_2/switch/configuration/guide/xcftagov_external_docbase_0900e4b180753c36_4container_external_docbase_0900e4b180754411.html#wp1006819

Also from my experience and understanding there is little gain from enabling MPLS TE in a network consisting only of 3 PE routers.

But without better knowledge about your topology and requirements I cannot give a sound advice what to do, except to recommend you to gain more knowledge about MPLS TE.

Hope this helps! Please use the rating system.

Regards, Martin

mike_perry · ‎04-17-2008

Perhaps you may be able to offer some direction. MPLS-TE may not be what I am trying to acheive.

Our WAN cloud will be a mesh between 3 campuses. Our provider will provide Layer 2 transport services, 1Gbps, FIFO. At each campus I will be running 2821 for WAN edge.

All services will be converged onto this WAN, Voice, Video, Data.

At each campus runs 3750 or 6513 as Campus Core peering 2821's. Each campus will be running VRF-Lite. My goal is to become the MPLS service provider for the college. The 2821's are the PE devices and the Campus Core's are the CE devices. Example, Voice will have it's own VRF at each respective site, each vrf will learn routes from other voice vrf's from the 2821's. Currently the 2821's peer each other iBGP. I want to be able to allocate portions of bandwidth (1Gb) for each VRF on the WAN and queue the traffic within each VRF.