By default, routers share routes with other routers running the same protocol. In a multi-protocol environment, you must configure route redistribution for cross-protocol route sharing.
You can exclude an interface from route redistribution by adding a deny criterion for its network. From NSX 6.2, the HA (management) interface of a logical (distributed) router is automatically excluded from route redistribution.
- Log in to the vSphere Web Client.
- Click Networking & Security and then click NSX Edges.
- Double-click an NSX Edge.
- Click Routing and then click Route Redistribution.
- Click Edit next to Route Redistribution Status.
- Select the protocols for which you enable route redistribution and click OK.
- Add an IP prefix.
Entries in the IP Prefix list are processed sequentially.
- Click the Add icon in IP Prefixes.
- Type a name and IP address of the network.
The IP prefix entered is exactly matched, except if you include less-than-or-equal-to (LE) or greater-than-or-equal-to (GE) modifiers.
- LE and GE together specify a range of prefix lengths that the rule must match. You can add IP prefix GE as minimum prefix length to be matched and IP prefix LE as maximum prefix length to be matched.
You can use these two options individually or in conjunction. Value for LE and GE cannot be zero or greater than 32. GE value cannot be greater than LE value. For example,
If you provide a prefix as 10.0.0.0/16 and LE = 28, then the redistribution rule matches all prefixes ranging from 10.0.0.0/16 to 10.0.0.0/28. It means that the rule matches all prefix lengths from 16 to 28. Prefix 10.0.2.0/24 is matched.
If you provide a prefix as 10.0.0.0/16 and GE = 24, then the redistribution rule matches all prefixes ranging from 10.0.0.0/24 to 10.0.0.0/32. Prefix 10.0.0.16/28 is matched.
If you provide GE = 24 and LE = 28, then the redistribution rule matches all prefixes ranging from 10.0.0.0/24 to 10.0.0.0/28. Prefix 10.0.0.32/27 is matched.
- Click OK.
- Specify redistribution criteria for the IP prefix.
- Click the Add icon in Route Redistribution table.
- In Prefix Name, select the IP prefix added earlier.
- In Learner Protocol, select the protocol that is to learn routes from other protocols.
- In Allow Learning from, select the protocols from which routes should be learned.
- In Action, select Permit for exact subnet to redistribute, or select Deny.
- Click OK.
- Click Publish Changes.