Create a Traffic Distribution Profile

An SD-WAN policy rule references a Traffic Distribution profile to distribute sessions and to fail over to a better path when path quality deteriorates.
Based on your SD-WAN configuration plan, create the SD-WAN Traffic Distribution Profiles you need based on how you want the applications in your SD-WAN policy rules to be session loaded and to fail over.
  1. Ensure you already configured the Link Tags in an SD-WAN interface profile and committed and pushed them. The Link Tags must be pushed to your hubs and branches in order for Panorama™ to successfully associate the Link Tags you specify in this Traffic Distribution profile to an SD-WAN interface profile.
  2. Select a
    Device Group
  3. Create a Traffic Distribution profile.
    1. Select
      SD-WAN Link Management
      Traffic Distribution Profile
    2. Add
      a Traffic Distribution profile by
      using a maximum of 31 alphanumeric characters.
    3. Select
      only if you want to use this traffic distribution profile across all Device Groups (both hubs and branches).
    4. Select one traffic distribution method and add a maximum of four Link Tags that use this method for this profile.
      • Best Available Path
        one or more
        Link Tags
        . During the initial packet exchanges, before App-ID has classified the application in the packet, the firewall uses the path in the tag that has the best health metrics (based on the order of tags). After the firewall identifies the application, it compares the health (path quality) of the path it was using to the health of the first path (interface) in the first Link Tag. If the original path’s health is better, it remains the selected path; otherwise, the firewall replaces the original path. The firewall repeats this process until it has evaluated all the paths in the Link Tag. The final path is the path the firewall selects when a packet arrives that meets the match criteria.
        When a link becomes unqualified and must fail over to the next best path, the firewall can migrate a maximum of 1,000 sessions per minute from the unqualified link to the next best path. For example, suppose tunnel.901 has 3,000 sessions; 2,000 of those sessions match SD-WAN policy rule A and 1,000 sessions match SD-WAN policy rule B (both rules have a traffic distribution policy configured with
        Best Path Available
        ). If tunnel.901 becomes unqualified, it takes three minutes to migrate the 3,000 sessions from the unqualified link to the next best path.
      • Top Down Priority
        one or more
        Link Tags
        . The firewall distributes new sessions (that meet the match criteria) to links using the top-to-bottom order of the
        Link Tags
        you added. The firewall examines the first tag configured for this profile, and examines the paths that use that tag, selecting the first path it finds that is qualified (that is at or below the Path Quality thresholds for this rule). If no qualified path is found from that Link Tag, firewall examines the paths that use the next Link Tag. If the firewall finds no path after examining all paths in all of the Link Tags, the firewall uses the
        Best Available Path
        method. The first path selected is the preferred path until one of the Path Quality thresholds for that path is exceeded, at which point the firewall again starts at the top of the Link Tag list to find the new preferred path.
        If you have only one link at the hub, that link supports all of the virtual interfaces and DIA traffic. If you want to use the link types in a specific order, you must apply a Traffic Distribution profile to the hub that specifies
        Top Down Priority
        , and then order the Link Tags to specify the preferred order. If you apply a Traffic Distribution profile that instead specifies
        Best Available Path
        , the firewall will use the link, regardless of cost, to choose the best performing path to the branch. In summary, Link Tags in a Traffic Distribution profile, the Link Tag applied to a hub virtual interface, and a
        VPN Failover Metric
        in an SD-WAN Interface Profile work only when the Traffic Distribution profile specifies
        Top Down Priority
      • Weighted Session Distribution
        one or more
        Link Tags
        and then enter the
        percentage for each
        Link Tag
        so that the weights total 100%. The firewall performs session load distribution between Link Tags until their percentage maximums are reached. If there is more than one path in the Link Tag, the firewall distributes equally using round-robin until the path health metrics are reached, and then distributes sessions to the other member(s) that are not at the limit.
      If multiple physical interfaces have the same tag, the firewall distributes matching sessions evenly among them. If all paths fail a health (path quality) threshold, the firewall selects the path that has the best health statistics. If no SD-WAN links are available (perhaps due to a blackout), the firewall uses static or dynamic routing to route the matching packets.
      If a packet is routed to a virtual SD-WAN interface, but the firewall cannot find a preferred path for the session based on the SD-WAN policy’s Traffic Distribution profile, the firewall implicitly uses the Best Available Path method to find the preferred path. The firewall distributes any application sessions that don’t match an SD-WAN policy rule based on the firewall’s implicit, final rule, which distributes the sessions in round-robin order among all available links, regardless of the Traffic Distribution profile.
      If you prefer to control how the firewall distributes unmatched sessions, create a final catch-all rule to Distribute Unmatched Sessions to specific links in the order you specify.
    5. (
      ) After adding Link Tags, use the
      Move Up
      Move Down
      arrows to change the order of tags in the list, so they reflect the order in which you want the firewall to use links for this profile and for the selected applications in the SD-WAN policy rule.
    6. Click
  4. Commit
    Commit and Push
    your configuration changes.
  5. Commit
    your changes.

Recommended For You