On the ingress router, create a constrained-path LSP in which the JUNOS software makes most of the forwarding decisions, taking into account the hop constraints listed in the path statements. The LSP is adaptive so that no bandwidth double-counting occurs on links shared by primary and secondary paths. To acquire the necessary link bandwidth, this LSP is allowed to preempt lower priority sessions. Finally, this path always keeps the secondary path in hot-standby state for quick failover.
- [edit protocols]
- mpls {
-
- path to-hastings {
- 14.1.1.1 loose;
- }
-
- path alt-hastings {
- 12.1.1.1 loose;
- 11.1.1.1 strict;
- }
-
- label-switched-path hastings {
- to 11.1.1.1;
- bandwidth 10m; # Reserve 10 Mbps
- priority 0 0; # Preemptive, but not preemptable
- adaptive; # Set adaptivity
- primary to-hastings;
-
- secondary alt-hastings {
- standby;
- bandwidth 1m; # Reserve only 1 Mbps for the secondary
path
- }
- }
- interface all;
- }