67
Step Command
Remarks
5.
Configure the link
attribute.
mpls te link-attribute
attribute-value
By default, the link attribute
value is 0x00000000.
Advertising link TE attributes by using IGP TE extension
Both OSPF and IS-IS are extended to advertise link TE attributes. The extensions are called OSPF TE and
IS-IS TE. If both OSPF TE and IS-IS TE are available, OSPF TE takes precedence.
Configuring OSPF TE
OSPF TE uses Type-10 opaque LSAs to carry the TE attributes for a link. Before you configure OSPF TE,
you must enable opaque LSA advertisement and reception by using the
opaque-capability enable
command. For more information about opaque LSA advertisement and reception, see
Layer 3—IP
Routing Configuration Guide
.
MPLS TE cannot reserve resources and distribute labels for an OSPF virtual link, and cannot establish a
CRLSP through an OSPF virtual link. Therefore, make sure no virtual link exists in an OSPF area before
you configure MPLS TE.
To configure OSPF TE:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter OSPF view.
ospf
[
process-id
]
N/A
3.
Enable opaque LSA
advertisement and
reception.
opaque-capability enable
By default, opaque LSA
advertisement and reception are
enabled.
For more information about this
command, see
Layer 3—IP Routing
Command Reference
.
4.
Enter area view.
area
area-id
N/A
5.
Enable MPLS TE for the OSPF
area.
mpls te enable
By default, an OSPF area does not
support MPLS TE.
Configuring IS-IS TE
IS-IS TE uses a sub-TLV of the extended IS reachability TLV (type 22) to carry TE attributes. Because the
extended IS reachability TLV carries wide metrics, specify a wide metric-compatible metric style for the
IS-IS process before enabling IS-IS TE. Available metric styles for IS-IS TE include wide, compatible, or
wide-compatible. For more information about IS-IS, see
Layer 3—IP Routing Configuration Guide
.
To make sure IS-IS LSPs can be flooded on the network, specify an MTU that is equal to or greater than
512 bytes on each IS-IS enabled interface, because of the following:
•
The length of the extended IS reachability TLV might reach the maximum of 255 bytes.
•
The LSP header takes 27 bytes and the TLV header takes two bytes.
•
The LSP might also carry the authentication information.
To configure IS-IS TE: