H3C Technologies H3C S6800 Series Switches - Manual (Page 80)

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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: