H3C Technologies H3C SecBlade LB Cards - Manual (Page 102)

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Step 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.
• Approach 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 ]
• Approach 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 approach.
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 may be discarded. For example, configure PBR to forward packets that
match certain criteria through a specified 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.
• The Negative state of the track entry shows that the object is not available, and the apply clause is
invalid.
• The Invalid state of the track entry shows that the apply clause is valid.
The following objects can be associated with a track entry:
• Outgoing interface.
• Next hop.
• Default outgoing interface.
• Default next hop.
Configuration prerequisites
Before you associate Track with PBR, create a policy or a policy node and configure the match criteria as
well.