R2511-HP MSR Router Series High Availability Configuration Guide(V5)

29
• If the Track module detects the next hop accessibility of the static route in a private network through
NQA, the VPN instance name of the next hop of the static route must be consistent with that
configured for the NQA test group. Otherwise, accessibility detection cannot function correctly.
• If a static route needs route recursion, the associated track entry must monitor the next hop of the
recursive route instead of that of the static route. Otherwise, a valid route might be considered
invalid. For more information about static route configuration, see Layer 3
— IP Routing
Configuration Guide.
To associate Track with static routing:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Associate the static
route with a track
entry to check the
accessibility of the
next hop.
• Method 1:
ip route-static dest-address { mask |
mask-length } { next-hop-address |
vpn-instance d-vpn-instance-name
next-hop-address } track track-entry-number
[ preference preference-value ] [ tag
tag-value ] [ description description-text ]
• Method 2:
ip route-static vpn-instance
s-vpn-instance-name&<1-6> dest-address
{ mask | mask-length } { next-hop-address
track track-entry-number [ public ] |
vpn-instance d-vpn-instance-name
next-hop-address track track-entry-number }
[ preference preference-value ] [ tag
tag-value ] [ description description-text ]
Use either method.
Not configured by default.
Associating Track with PBR
Policy-based routing (PBR) is a routing mechanism based on user-defined policies. Different from the
traditional destination-based routing mechanism, PBR allows you to use a policy (based on the source
address, packet length, and other criteria) to route packets. You can specify the VPN instance, packet
priority, outgoing interface, next hop, default outgoing interface, default next hop, and other parameters
to guide the forwarding of packets that match specific ACLs or have specific lengths.
PBR cannot detect the availability of any action taken on packets. When an action is not available,
packets processed by the action might be discarded. For example, configure PBR to forward packets that
match certain criteria through a specific interface. When the specified interface fails, PBR cannot sense
the failure, and continues to forward matching packets out of the interface.
This problem can be solved by associating Track with PBR, which improves the flexibility of the PBR
application and enables PBR to sense topology changes.
After you associate a track entry with an apply clause, the detection module associated with the track
entry sends the detection result of the availability of the object (an interface or an IP address) specified
in the apply clause.
• The Positive state of the track entry shows that the object is available, and the apply clause is valid.