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source-packet-routing (Protocols OSPF)


Hierarchy Level


Configures source packet routing in networking (SPRING) feature.


Disabled on all the levels.


adjacency-segment <hold-time hold-time>

Configure attributes for adjacency segments in source packet routing in networking (SPRING), or configure segment routing (SR) to ensure that the adjacency segment identifiers are retained during adjacency or link flaps. The adjacency segments are not released immediately and are retained for the configured hold time duration.

  • hold-time hold-time—(Optional) Duration, in milliseconds, to retain adjacency segments after isolating from an interface. The range is 180,000 through 900,000, with the default being 300,000 milliseconds for IS-IS interfaces and 180,000 milliseconds for OSPF interfaces.


Disable source packet routing from a specific level.


Configure E and P bits in all prefix segment identifier (SID) advertisements.


Enable source packet routing in networking (SPRING) at all levels. SPRING or segment routing is a control-plane architecture that enables an ingress router to steer a packet through a specific set of nodes and links in the network without relying on the intermediate nodes in the network to determine the actual path it should take.


Provisioning the IPv4 and IPv6 node segment index is allowed per routing-instance, and will NOT be allowed per IS-IS level. Node segment index is attached to the IPv4 and IPv6 router-id, if the router-ids are configured on the loopback interface. Else, lowest IP address on the loopback is chosen to attach the node-sid.

index-range index range

Range of node segment indices allowed. The range is 32 through 16384, and the default is 4096.

ipv4-index index

IPv4 node segment index. The range is 0 through 199999.


Starting with Junos OS Release 17.2, the maximum index for IPv4 node segment index is 199999.

ipv6-index index

IPv6 node segment index. The range is 0 through 199999.


Starting with Junos OS Release 17.2, the maximum index for IPv6 node segment index is 199999.

strict-asla-based-flex-algorithm Specify to indicate flexible algorithm path computations to use only the links that advertise relevant te-attributes through Application-Specific Link Attributes (ASLA).

The option source-packet-routing strict-asla-based-flex-algorithm has to be applied to all the flexible algorithms running on the devices in the network to avoid routing loops.

The remaining statements are explained separately. See CLI Explorer.

Required Privilege Level

routing—To view this statement in the configuration.

routing-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 16.2.

The strict-asla-based-flex-algorithm option introduced in Junos OS and Junos OS Evolved Release 22.2R1.