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Link monitoring and failover

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Performance SLA link monitoring measures the health of links that are connected to SD-WAN member interfaces by sending probing signals through each link to a server, and then measuring the link quality based on latency, jitter, and packet loss. If a link is broken, the routes on that link are removed and traffic is routed through other links. When the link is working again, the routes are re-enabled. This prevents traffic being sent to a broken link and lost.

In this example, the detection server IP address is 208.91.112.53. A performance SLA is created so that, if ping fails per the metrics defined, the routes to that interface are removed and traffic is detoured to the other interface. The ping protocol is used, but other protocols could also be selected as required.

To configure a performance SLA:
  1. Go to Network > Performance SLA.
  2. Click Create New. The Performance SLA page opens.
  3. Enter a name for the SLA and select a protocol.
  4. In the Server field, enter the detection server IP address (208.91.112.53 in this example).
  5. In the Participants field, select both wan1 and wan2.

    SLA targets are not required for link monitoring.

  6. Configure the required metrics in Link Status.
  7. Ensure that Update static route is enabled. This disables static routes for the inactive interface and restores routes on recovery.
  8. Click OK.

Next: Results

Performance SLA link monitoring measures the health of links that are connected to SD-WAN member interfaces by sending probing signals through each link to a server, and then measuring the link quality based on latency, jitter, and packet loss. If a link is broken, the routes on that link are removed and traffic is routed through other links. When the link is working again, the routes are re-enabled. This prevents traffic being sent to a broken link and lost.

In this example, the detection server IP address is 208.91.112.53. A performance SLA is created so that, if ping fails per the metrics defined, the routes to that interface are removed and traffic is detoured to the other interface. The ping protocol is used, but other protocols could also be selected as required.

To configure a performance SLA:
  1. Go to Network > Performance SLA.
  2. Click Create New. The Performance SLA page opens.
  3. Enter a name for the SLA and select a protocol.
  4. In the Server field, enter the detection server IP address (208.91.112.53 in this example).
  5. In the Participants field, select both wan1 and wan2.

    SLA targets are not required for link monitoring.

  6. Configure the required metrics in Link Status.
  7. Ensure that Update static route is enabled. This disables static routes for the inactive interface and restores routes on recovery.
  8. Click OK.

Next: Results