Why MPLS backbone support only ISIS or OSPF as an IGP protocol?

[mukupatil]

Why MPLS backbone support only ISIS or OSPF as an IGP protocol?

[Raju Sekharan]

Hi

You need a link state protocol if you want to run MPLS TE

MPLS TE requires an IGP capable of sending all the topology information to all routers in the area in which TE has been enabled. Only link state protocols can do this

Thanks

Raju

[Mohammed Imran Khan]

Hi,

There is absolutely no restriction of using the IGP within the backbone. You can even use EIGRP. As rajs2 has already told, then you will not be able to run the MPLS TE, as it uses the capabilities of IGP (LSA in case of OSPF and TLVs in case of ISIS).

Thanks,

Imran

[Nagendra Kumar Nainar · Accepted solution]

Hi,

It is still possible to run MPLS TE when IGP is non link state protocol (For example, EIGRP). You need to configure TE tunnel with explicit path and enable vertabitm. Normally, when you have explicit path configured, it still will perform a check in TE database. But enabling verbatim will disable this check and make it possible to enable in EIGRP cloud.

Thanks,

Nagendra