Segment Routing

Segment routing (segment-routing) steers traffic along a path encoded as a list of segments. SR-MPLS settings (segment-routing > mpls) cover the segment routing global block (SRGB), the SRGB cleanup and retry timers, shutdown and the connected prefix SID map that assigns an index or absolute label to local prefixes per address family. SRv6 settings (segment-routing > srv6) cover the encapsulation source address and the locators with their prefixes. SR-TE settings (segment-routing > traffic-engineering) cover the MPLS encapsulation source address, liveness detection, the PCC source address and PCE addresses, the affinity map, TE interfaces with metric and affinity colors, explicit segment lists, SRv6 locators, on-demand colors (ODN) and SR-TE policies. On-demand colors and policies support shutdown, lockdown, liveness detection and candidate paths, each with explicit segment lists, dynamic path computation (locally or through PCEP) and constraints (segments, disjointness association group, affinity).

Note

SR-MPLS requires feature_set.mpls, feature.mpls_segment_routing and, for SR-TE, feature.mpls_segment_routing_traffic_engineering. SRv6 requires feature.srv6, which cannot be enabled together with feature mpls segment-routing. An SRv6 locator prefix must be a /64 prefix. A candidate path preference supports either explicit segment lists or constraints, and its constraints support either affinity or an association group, with only one of include-all, include-any or exclude-any affinity. Each on-demand color and policy supports only one preference with dynamic path computation or constraints, and an on-demand color must not use the color of an explicit policy.

Diagram

Classes

nxos

Name	Type	Constraint	Mandatory	Default Value
devices	List	devices	No
device_groups	List	device_groups	No
global	Class	global	No
templates	List	templates	No

devices (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

device_groups (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

global (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

templates (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

configuration (nxos.devices)

Name	Type	Constraint	Mandatory	Default Value
routing	Class	routing	No

routing (nxos.devices.configuration)

Name	Type	Constraint	Mandatory	Default Value
segment_routing	Class	segment_routing	No

segment_routing (nxos.devices.configuration.routing)

Name	Type	Constraint	Mandatory	Default Value
mpls	Class	mpls	No
srv6	Class	srv6	No
traffic_engineering	Class	traffic_engineering	No

mpls (nxos.devices.configuration.routing.segment_routing)

Name	Type	Constraint	Mandatory	Default Value
shutdown	Boolean	true, false	No
global_block_min	Integer	min: 16000, max: 471804	No
global_block_max	Integer	min: 16000, max: 471804	No
timers_srgb_cleanup	Integer	min: 1, max: 65535	No
timers_srgb_retry	Integer	min: 1, max: 65535	No
connected_prefix_sid_map_address_families	List	connected_prefix_sid_map_address_families	No

srv6 (nxos.devices.configuration.routing.segment_routing)

Name	Type	Constraint	Mandatory	Default Value
encapsulation_source_address	IP		No
locators	List	locators	No

traffic_engineering (nxos.devices.configuration.routing.segment_routing)

Name	Type	Constraint	Mandatory	Default Value
encapsulation_mpls_source_ipv4	IP		No
liveness_detection_interval	Integer	min: 50, max: 30000	No
liveness_detection_multiplier	Integer	min: 1, max: 10	No
liveness_detection_mpls_bfd	Boolean	true, false	No
liveness_detection_mpls_oam	Boolean	true, false	No
pcc_source_address_ipv4	IP		No
pcc_pce_addresses	List	pcc_pce_addresses	No
affinity_map_colors	List	affinity_map_colors	No
segment_routing_srv6_locators	List	String	No
interfaces	List	interfaces	No
segment_lists	List	segment_lists	No
on_demand_colors	List	on_demand_colors	No
policies	List	policies	No

connected_prefix_sid_map_address_families (nxos.devices.configuration.routing.segment_routing.mpls)

Name	Type	Constraint	Mandatory	Default Value
address_family	Choice	ipv4, ipv6	Yes
prefixes	List	prefixes	No

locators (nxos.devices.configuration.routing.segment_routing.srv6)

Name	Type	Constraint	Mandatory	Default Value
name	String		Yes
prefix	IP		No

pcc_pce_addresses (nxos.devices.configuration.routing.segment_routing.traffic_engineering)

Name	Type	Constraint	Mandatory	Default Value
ipv4	IP		Yes
precedence	Integer	min: 0, max: 255	No

affinity_map_colors (nxos.devices.configuration.routing.segment_routing.traffic_engineering)

Name	Type	Constraint	Mandatory	Default Value
color	String		Yes
bit_position	Integer	min: 0, max: 31	No

interfaces (nxos.devices.configuration.routing.segment_routing.traffic_engineering)

Name	Type	Constraint	Mandatory	Default Value
interface_type	Choice	ethernet, loopback, mgmt, port-channel, vlan, vni	Yes
interface_id	Any	String or Integer[min: 0]	Yes
metric	Integer	min: 0, max: 4294967295	No
affinity_colors	List	String	No

segment_lists (nxos.devices.configuration.routing.segment_routing.traffic_engineering)

Name	Type	Constraint	Mandatory	Default Value
name	String		Yes
indexes	List	indexes	No

on_demand_colors (nxos.devices.configuration.routing.segment_routing.traffic_engineering)

Name	Type	Constraint	Mandatory	Default Value
color	Integer	min: 0, max: 4294967295	Yes
shutdown	Boolean	true, false	No
lockdown	Boolean	true, false	No
liveness_detection	Class	liveness_detection	No
candidate_paths_preferences	List	candidate_paths_preferences	No

policies (nxos.devices.configuration.routing.segment_routing.traffic_engineering)

Name	Type	Constraint	Mandatory	Default Value
name	String		Yes
color	Integer	min: 0, max: 4294967295	No
endpoint	IP		No
shutdown	Boolean	true, false	No
lockdown	Boolean	true, false	No
liveness_detection	Class	liveness_detection	No
candidate_paths_preferences	List	candidate_paths_preferences	No

prefixes (nxos.devices.configuration.routing.segment_routing.mpls.connected_prefix_sid_map_address_families)

Name	Type	Constraint	Mandatory	Default Value
prefix	IP		Yes
index	Integer	min: 0, max: 471804	No
absolute	Integer	min: 16000, max: 471804	No

indexes (nxos.devices.configuration.routing.segment_routing.traffic_engineering.segment_lists)

Name	Type	Constraint	Mandatory	Default Value
index	Integer	min: 1, max: 65535	Yes
mpls_label	Integer	min: 16, max: 471804	No
segment_routing_srv6	IP		No
policy_endpoint	Boolean	true, false	No

liveness_detection (nxos.devices.configuration.routing.segment_routing.traffic_engineering.on_demand_colors)

Name	Type	Constraint	Mandatory	Default Value
shutdown	Boolean	true, false	No
index_limit	Integer	min: 0, max: 65535	No
mpls_bfd	Boolean	true, false	No
mpls_oam	Boolean	true, false	No

candidate_paths_preferences (nxos.devices.configuration.routing.segment_routing.traffic_engineering.on_demand_colors)

Name	Type	Constraint	Mandatory	Default Value
preference	Integer	min: 0, max: 4294967295	Yes
shutdown	Boolean	true, false	No
explicit_segment_lists	List	String	No
dynamic	Boolean	true, false	No
dynamic_pcep	Boolean	true, false	No
dynamic_metric_type	Choice	igp	No
constraints_segments_dataplane_mpls	Boolean	true, false	No
constraints_segments_protected	Boolean	true, false	No
constraints_segments_unprotected	Boolean	true, false	No
constraints_association_group_disjoint_type	Choice	link, node	No
constraints_association_group_disjoint_id	Integer	min: 0, max: 4294967295	No
constraints_affinity_include_all_colors	List	String	No
constraints_affinity_include_any_colors	List	String	No
constraints_affinity_exclude_any_colors	List	String	No

Examples

Example 1: SR-MPLS with an SRGB and connected prefix SIDs

nxos:
  devices:
    - name: PE1
      configuration:
        feature_set:
          mpls: true
        feature:
          mpls_segment_routing: true
        routing:
          segment_routing:
            mpls:
              global_block_min: 17000
              global_block_max: 25999
              timers_srgb_cleanup: 90
              timers_srgb_retry: 120
              connected_prefix_sid_map_address_families:
                - address_family: ipv4
                  prefixes:
                    - prefix: 10.0.0.1/32
                      index: 1
                    - prefix: 10.0.0.101/32
                      absolute: 17101

Example 2: SR-TE with PCC, affinities, an on-demand color and an explicit policy

nxos:
  devices:
    - name: PE1
      configuration:
        feature_set:
          mpls: true
        feature:
          mpls_segment_routing: true
          mpls_segment_routing_traffic_engineering: true
        routing:
          segment_routing:
            mpls:
              global_block_min: 16000
              global_block_max: 23999
            traffic_engineering:
              encapsulation_mpls_source_ipv4: 10.0.0.1
              pcc_source_address_ipv4: 10.0.0.1
              pcc_pce_addresses:
                - ipv4: 10.0.0.100
                  precedence: 10
              affinity_map_colors:
                - color: RED
                  bit_position: 1
              interfaces:
                - interface_type: ethernet
                  interface_id: 1/1
                  metric: 10
                  affinity_colors:
                    - RED
              segment_lists:
                - name: TO-PE2
                  indexes:
                    - index: 10
                      mpls_label: 16002
                    - index: 20
                      policy_endpoint: true
              on_demand_colors:
                - color: 100
                  candidate_paths_preferences:
                    - preference: 100
                      dynamic: true
                      dynamic_pcep: true
                      dynamic_metric_type: igp
                      constraints_segments_dataplane_mpls: true
                      constraints_segments_protected: true
                      constraints_affinity_include_all_colors:
                        - RED
              policies:
                - name: PE1-TO-PE2
                  color: 200
                  endpoint: 10.0.0.2
                  liveness_detection:
                    index_limit: 10
                  candidate_paths_preferences:
                    - preference: 100
                      explicit_segment_lists:
                        - TO-PE2
                    - preference: 50
                      dynamic: true
                      constraints_association_group_disjoint_type: link
                      constraints_association_group_disjoint_id: 2

Example 3: SRv6 locator and encapsulation source address

nxos:
  devices:
    - name: PE2
      configuration:
        feature:
          srv6: true
        routing:
          segment_routing:
            srv6:
              encapsulation_source_address: 2001:db8::2
              locators:
                - name: LOC1
                  prefix: 2001:db8:0:2::/64