Configuring TE Attributes

TE attributes configured for links are advertised to IS-IS. IS-IS advertises these attributes to BGP-LS, which then advertises them to a controller. This enables the controller to adjust links based on the TE attributes during SRv6 TE Policy calculation.

Context

TE link attributes are as follows:

Link bandwidth

This attribute is mandatory if you want to limit the bandwidth of a path of an SRv6 TE Policy.
Link-specific TE metric

The IGP metric or link-specific TE metric can be used for SRv6 TE Policy computation by a controller. This makes SRv6 TE Policy computation more independent of the IGP, facilitating path control.
Administrative group and affinity attribute

The affinity attribute of an SRv6 TE Policy determines the link attributes used by the policy. The administrative group and affinity attribute are used together to determine the links that can be used by the policy.
SRLG

A shared risk link group (SRLG) is a group of links that share a public physical resource, such as an optical fiber. Links in an SRLG are at the same risk of faults. If one of the links fails, other links in the SRLG also fail.

An SRLG enhances SRv6 TE Policy reliability on a network with CR-LSP hot standby or TE FRR enabled. Links that share the same physical resource have the same risk. For example, links on an interface and its sub-interfaces are in an SRLG. The interface and its sub-interfaces have the same risk. If the interface goes down, its sub-interfaces will also go down. If the link of the primary path of an SRv6 TE Policy and the links of the backup paths of the SRv6 TE Policy are in an SRLG and the primary path goes down, the backup paths will most likely go down.

To support SRv6 TE Policy over GRE, you can configure TE attributes on the desired GRE tunnel interface.

Procedure

Enable TE attributes.
1. Run system-view
  The system view is displayed.
2. Run te attribute enable
  The function to convert MPLS TE attributes into TE attributes and to configure TE attributes is enabled.
  
  If MPLS TE has been enabled, this function converts MPLS TE attributes into TE attributes. You can also configure new TE attributes. The converted TE attributes can be used for both MPLS TE tunnels and SRv6 TE Policies.
(Optional) Configure link bandwidth.
In real-world applications, link bandwidth only needs to be configured for outbound interfaces along the links of an SRv6 TE Policy that requires sufficient bandwidth.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view of a TE link is displayed.
3. Run te bandwidth max-reservable-bandwidth max-bw-value
  The maximum reservable link bandwidth is configured.
4. Run te bandwidth bc0 bc0Bw
  The BC0 bandwidth is configured for the link.
  - The maximum reservable link bandwidth cannot be higher than the physical link bandwidth. You are advised to set the maximum reservable link bandwidth to be less than or equal to 80% of the physical link bandwidth.
  - The BC0 bandwidth cannot be higher than the maximum reservable link bandwidth.
5. Run commit
  The configuration is committed.
(Optional) Configure a TE metric value for a link.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view of a TE link is displayed.
3. Run te metric metric-value
  A TE metric value is configured for the link.
4. Run commit
  The configuration is committed.
(Optional) Configure the administrative group and affinity attribute in hexadecimal format.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view of a TE link is displayed.
3. Run te link administrative group group-value
  A TE link administrative group is configured.
4. Run commit
  The configuration is committed.
(Optional) Configure the link administrative group and affinity attributes.
1. Run system-view
  The system view is displayed.
2. Run path-constraint affinity-mapping
  An affinity name template is configured, and the template view is displayed.
  
  This template must be configured on each node that is involved in computing an SRv6 TE Policy, and the same mappings between affinity names and values must be configured on each node.
3. Run attribute bit-name bit-sequence bit-number
  Mappings between affinity bit values and names are configured.
  
  An affinity attribute has a total of 128 bits. This step configures only one bit. Repeat this step to configure more bits. You can configure some or all of the bits in the affinity attribute.
4. Run quit
  Return to the system view.
5. Run interface interface-type interface-number
  The interface view of a TE link is displayed.
6. Run te link administrative group name name-string &<1-32>
  A TE link administrative group is configured.
  
  The name-string value must be in the range specified in the affinity name template.
7. Run commit
  The configuration is committed.
(Optional) Configure an SRLG.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view of a TE link is displayed.
3. Run te srlg srlg-number
  The interface is added to an SRLG.
  
  On a network with hot standby or TE FRR protection, you need to configure the SRLG attribute for the outbound interface of the ingress on an SRv6 TE Policy as well as other members in the SRLG. A link joins an SRLG after the SRLG attribute is configured on an outbound interface of the link.
  
  To delete the SRLG configuration from all interfaces on a device, run the undo te srlg all-config command.
4. Run commit
  The configuration is committed.