Configure Policy-Based Routing Policy

You can configure the PBR policy on the Policy Based Routing page by specifying the ingress interfaces, match criteria (Extended Access Control List), and egress interfaces.

Before you begin

To use the path monitoring metrics for configuring the traffic forwarding priority over egress interfaces, you must configure the path monitoring settings for the interfaces. See Configure Path Monitoring Settings.

Procedure


Step 1

Choose Devices > Device Management, and edit the threat defense device.

Step 2

Click Routing.

Step 3

Click Policy Based Routing.

The Policy Based Routing page displays the configured policy. The grid displays the list of ingress interfaces and a combination of the policy-based route access list, and egress interfaces.

Step 4

To configure the policy, click Add.

Step 5

In the Add Policy Based Route dialog box, select the Ingress Interface from the drop-down list.

Note

Only interfaces that have logical names and that belong to a global virtual router are listed in the drop-down.

Step 6

To specify the match criteria and the forward action in the policy, click Add.

Step 7

In the Add Forwarding Actions dialog box, do the following:

  1. From the Match ACL drop-down, choose the extended access control list object. You can predefine the ACL object (see Configure Extended ACL Objects) or click the Add (add icon) icon to create the object. In the New Extended Access List Object box, enter a name, click Add to open the Add Extended Access List Entry dialog box, where you can define the network, port, user identity, SGT, or application match criteria for the PBR policy.

    Note

    You can either have destination address or application/user identity/SGT defined in an ACE.

    To selectively apply PBR on the incoming interface, you can define Block criteria in the ACE. When the traffic matches the block rule of the ACE, the traffic is forwarded to the egress interface based on the routing table.

  2. From the Send To drop-down list:

    • To select the configured interfaces, choose Egress Interfaces.

    • To specify the IPv4/IPv6 next hop addresses, choose IP Address. Proceed to Step 7.e

  3. If you have selected Egress Interfaces, from the Interface Ordering drop-down, choose the relevant option:

    • By Interface Priority—The traffic is forwarded based on the priority of the interfaces. Traffic is routed to the interface with the least priority value first. When the interface is not available, the traffic is then forwarded to the interface with the next lowest priority value. For example, let us assume that Gig0/1, Gig0/2, and Gig0/3 are configured with priority values 0,1, and 2 respectively. The traffic is forwarded to Gig0/1. If Gig0/1 becomes unavailable, the traffic is then forwarded to Gig0/2.

      Note

      To configure the priority for the interfaces, click Configure Interface Priority on the Policy Based Routing page. In the dialog box, provide the priority number against the interfaces, and then click Save. You can also configure the priority for an interface in the Interface Settings.

      When the priority value is the same for all the interfaces, the traffic is balanced among the interfaces.

    • By Order—The traffic is forwarded based on the sequence of the interfaces specified here. For example, let us assume that Gig0/1, Gig0/2, and Gig0/3 are selected in the following order, Gig0/2, Gig0/3, Gig0/1. The traffic is forwarded to Gig0/2 first, then to Gig0/3, irrespective of their priority values.

    • By Minimal Jitter—The traffic is forwarded to the interface that has the lowest jitter value. You need to enable Path Monitoring on the interfaces for PBR to obtain the jitter values.

    • By Maximum Mean Opinion Score—The traffic is forwarded to the interface that has the maximum mean opinion score (MOS). You need to enable Path Monitoring on the interfaces for PBR to obtain the MOS values.

    • By Minimal Round Trip Time—The traffic is forwarded to the interface that has the minimal round trip time (RTT). You need to enable Path Monitoring on the interfaces for PBR to obtain the RTT values.

    • By Minimal Packet Loss—The traffic is forwarded to the interface that has the minimal packet loss. You need to enable Path Monitoring on the interfaces for PBR to obtain the packet loss values.

  4. In the Available Interfaces box, all the interfaces with their priority values are listed. From the list of interfaces, click the Add (add icon) button to add to the selected egress interfaces. Proceed to Step 7.k

  5. If you have selected IP Address, enter the IP addresses separated by commas in the IPv4 Addresses or IPv6 Addresses fields.

    Note

    When multiple next-hop IP addresses are provided, the traffic is forwarded as per the sequence of the specified IP addresses until a valid routable next-hop IP address is found. The configured next-hops should be directly connected.

  6. From the Don't Fragment drop-down list, select Yes, No, or None. If the DF (Don't Fragment) flag is set to Yes, the intermediate routers never perform fragmentation of a packet.

  7. To specify the current interface as the default for forwarding, check the Default Interface check box.

  8. The IPv4 Settings and IPv6 Settings tab enables you to specify the recursive and default settings:

    Note

    For a route-map, you can only specify either IPv4 or IPv6 next-hop settings.

    • Recursive—The route map configuration is applied only when the specified next-hop address and the default next-hop address are found on a directly connected subnet. However, you could use the recursive option, where the next-hop address need not be directly connected. Here, a recursive lookup is performed on the next-hop address, and matching traffic is forwarded to the next-hop used by that route entry according to the current routing path of the router.

    • Default—If the normal route lookup fails to match traffic, the traffic is forwarded to this specified next-hop IP address.

  9. Check the Peer Address check box to use the next-hop address as the peer address.

    Note

    You cannot configure a route map with both default next-hop address and peer address.

  10. For IPv4 settings, you can check whether the next IPv4 hops of a route map are available under Verify Availability—click the Add (add icon) button and add the next-hop IP address entries:

    • IP Address—Enter the next hop IP address.

    • Sequence—Entries are assessed in order using the sequence number. Ensure that no duplicate sequence numbers are entered. The valid range is 1 to 65535.

    • Track—Enter a valid ID. The valid range is 1 to 255.

  11. Click Save.

Step 8

To save the policy, click Save and Deploy.


The threat defense uses ACLs to match traffic and perform routing actions on the traffic. Typically, you configure a route map that specifies an ACL against which traffic is matched, and then you specify one or more actions for that traffic. With the use of path monitoring, PBR can now select the best egress interface for routing the traffic. Finally, you associate the route map with an interface on which you want to apply PBR on all incoming traffic.