An explicit path is configured on the ingress of an MPLS TE tunnel to define the nodes through which the MPLS TE tunnel passes and the nodes that are excluded from the MPLS TE tunnel.
An explicit path consists of a series of nodes. These nodes are arranged in sequence and form a vector path. An IP address for an explicit path is an interface IP address on every node. The loopback IP address of the egress node is used as the destination address of an explicit path.
Two adjacent nodes on an explicit path are connected in either of the following modes:
Strict: A hop is directly connected to its next hop.
Loose: Other nodes may exist between a hop and its next hop.
The strict and loose modes can be used simultaneously.
TE tunnels are classified into the following types:
Intra-area tunnel: A TE tunnel is in a single OSPF or IS-IS area, but not in an autonomous system (AS) running the Border Gateway Protocol (BGP).
Inter-area tunnel: A TE tunnel traverses multiple OSPF or IS-IS areas, but not BGP ASs.
A strict explicit path is used to establish an inter-area TE tunnel, on which a next hop can only be an area border router (ABR) or an autonomous system boundary router (ASBR).
The system view is displayed.
An explicit path is created and the explicit path view is displayed.
The next-hop address is specified for the explicit path.
The include parameter indicates that the tunnel does pass through a specified node; the exclude parameter indicates that the tunnel does not pass through a specified node.
A node is added to the explicit path.
The address of a node on an explicit path is changed.
A node is excluded from an explicit path.
Information about nodes on an explicit path is displayed.
The configurations are committed.