Configuring an mpls te explicit path – H3C Technologies H3C S10500 Series Switches User Manual
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NOTE:
•
According to RFC 3784, the length of the IS reachability TLV (type 22) may reach the maximum of 255
bytes in some cases.
•
For an IS-IS LSP to carry this type of TLV and to be flooded normally on all interfaces with IS-IS enabled,
the MTU of any IS-IS enabled interface, including 27 bytes of LSP header and two bytes of TLV header,
cannot be less than 284 bytes. If an LSP must also carry the authentication information, the minimum
MTU must be recalculated according to the packet structure.
When TE is configured, set the MTU of any interface with IS-IS enabled be equal to or greater than 512
bytes to guarantee that IS-IS LSPs can be flooded on the network.
Follow these steps to configure IS-IS TE:
To do…
Use the command...
Remarks
Enter system view
system-view
––
Enter IS-IS view
isis [ process-id ] ––
Configure the wide metric attribute
of IS-IS
cost-style { narrow | wide |
wide-compatible | { compatible |
narrow-compatible }
[ relax-spf-limit ] }
Required
By default, IS-IS uses narrow metric
style.
Enable IS-IS TE
traffic-eng [ level-1 | level-2 |
level-1-2 ]
Required
Disabled by default
NOTE:
•
For more information about IS-IS, see
Layer 3—IP Routing Configuration Guide.
•
IS-IS TE does not support secondary IP address advertisement. With IS-IS TE enabled on an interface
configured with multiple IP addresses, IS-IS TE advertises only the primary IP address of the interface
through the sub-TLV of IS reachability TLV (type 22). H3C recommends avoiding enabling IS-IS TE on an
interface configured with secondary IP addresses.
Configuring an MPLS TE explicit path
An explicit path is a set of nodes. The relationship between any two neighboring nodes on an explicit
path can be either strict or loose.
•
Strict: The two nodes are directly connected.
•
Loose: The two nodes have devices in between.
When inserting nodes to an explicit path or modifying nodes on it, you can configure the include
keyword to have the established LSP traverse the specified nodes or the exclude keyword to have the
established LSP bypass the specified nodes.
Follow these steps to configure an MPLS TE explicit path:
To do…
Use the command...
Remarks
Enter system view
system-view
––
Create an explicit path for MPLS TE
tunneling and enter its view
explicit-path path-name [ disable |
enable ]
Required