backup-spf-options (Protocols OSPF)
Syntax
backup-spf-options {
disable;
downstream-paths-only;
no-install;
node-link-degradation;
per-prefix-calculation {
all;
externals;
stubs;
summary;
}
remote-backup-calculation;
}
Hierarchy Level
[edit logical-systems logical-system-name protocols (ospf | ospf3)], [edit logical-systems logical-system-name protocols ospf topology (default | name)], [edit logical-systems logical-system-name routing-instances routing-instance-name protocols (ospf | ospf3)], [edit logical-systems logical-system-name routing-instances routing-instance-name protocols ospf topology (default | name)], [edit protocols (ospf | ospf3)], [edit protocols ospf topology (default | name)], [edit routing-instances routing-instance-name protocols (ospf | ospf3)], [edit routing-instances routing-instance-name protocols ospf topology (default | name)]
Description
Configure options for running the shortest-path-first (SPF) algorithm for backup next hops for protected interfaces. Use these options to override the default behavior of having Junos OS calculate backup paths for all the topologies in an instance when at least one interface is configured with link protection or node-link protection. These options also enable you to change the default behavior for a specific topology in an OSPF instance.
Options
| disable | Do not calculate backup next hops for the specified instance or topology. |
| downstream-paths-only | Calculate and install only downstream paths as defined in RFC 5286, Basic Specification for IP Fast Reroute: Loop-Free Alternates for the specified instance or topology. |
| no-install | Do not install the backup next hops for the specified instance or topology. |
| node-link-degradation | Degrade an interface from node-link to link protection in case no node protection LFA route is found for a given destination node. A link protecting loop-free alternate (LFA) is used when node-link protecting LFA is not available in the topology for any of the protected links. |
| per-prefix-calculation | Calculate backup next hops for non-best prefix originators.
|
| remote-backup-calculation | Determine the remote LFA backup paths from the point of local repair (PLR) in an OSPF network. For every protected link on the PLR, Junos OS creates a dynamic LDP label-switched path to reach the remote LFA node. When the primary link fails, the PLR uses these remote LFA backup paths to reach all the destinations reachable through the primary-link. |
Required Privilege Level
routing—To view this statement in the configuration.
routing-control-level—To add this statement to the configuration.
Release Information
Statement introduced in Junos OS Release 10.0.
node-link-degradation, per-prefix-calculation, and remote-backup-calculation options introduced in
Junos OS Release 15.1.
Support for remote-backup-calculation option introduced
in Junos OS Release 18.2R1 for QFX5100, QFX5110, and QFX5200 switches.