Routing
A complete guide to EdgeConnect routing is beyond the scope of this document. Before troubleshooting, you should have an understanding of subnet sharing, peer priority, and route redistribution.
Routing Decisions
Routing decisions are made based on a well-known evaluation process:
- Longest Prefix Match
- Lowest Administrative Distance
- Lowest Metric
- Lowest Peer Priority
NOTE Peer Priority is a concept specific to EdgeConnect. If the first three values are equal, Peer Priority breaks the tie. If all values are equal and Peer Priority is not configured, traffic is load balanced over all peers involved in the tie.
Routes
To show routes learned by appliances in the fabric, click Configuration, and then click Routes. Use this information to confirm configuration for route presence, AD, metric, and more.
Find Preferred Route
Use this tool to determine traffic-forwarding decisions for traffic coming from the WAN or LAN, or for traffic self-generated by the appliance. To access the tool, click Configuration, and then click Routes. To edit one of the table entries, click the Pencil icon. The appliance-specific route page appears with a button displayed to load the tool.
NOTE If segmentation is enabled, make sure the entry selected is part of the segment under investigation.
The following example shows that self-generated traffic from this appliance, destined for 8.8.8.8, will be sent to the EAST2-AWS appliance, and that the route was learned over the SD-WAN fabric.
Common Issues
Issue | Resolution |
---|---|
Route not present on appliance from another appliance. | Confirm there is a tunnel up between the two appliances, or between the appliance and its hubs if using regional routing. |
Routes not being advertised to other appliances. | Confirm there is a tunnel up between the two appliances, or between the appliance and its hubs if using regional routing. |
Not enough or too many routes being seen from non-EdgeConnect devices. | Check inbound/outbound route maps for the routing protocol being used. |
Routes not being advertised to other network equipment. | Confirm the routing protocol is in the appropriate state. Confirm the route maps are configured properly. |