HP Manager Software manual Creating Static Routes

Configuring IP Services 227

For destination routes that are not directly attached, you can add static routes. A static route specifies the destination and the gateway router through which to forward traffic.You can add the following types of static routes:

„Explicit route — Forwarding path for traffic to a specific destination

„Default route — Forwarding path for traffic to a destination without an explicit route

If the IP routing table contains an explicit route for a given destination, MSS uses the route. Otherwise, MSS uses a default route. For example, if the routing table does not have a route to host 192.168.1.10, the WX uses the default route to forward a packet addressed to that host. 3Com recommends that you configure at least one default route.

A destination can be a subnet or network. If two static routes specify a destination, the more specific route is always chosen (longest prefix match). For example, if you have a static route with a destination of 10.10.1.0/24, and another static route with a destination of 10.10.0.0/16, the first static route is chosen to reach 10.10.1.15, because it has the longer prefix match.

Creating Static Routes

You can configure a maximum of four routes per destination. This includes default routes, which have a destination of 0.0.0.0/0. Each route to a given destination must have a unique gateway address. When the routing table contains multiple default routes or multiple explicit routes to the same destination, MSS uses the route with the lowest metric (cost for using the route). If two or more routes to the same destination have the lowest cost, MSS selects the first route in the routing table.

When you add multiple routes to the same destination, MSS groups the routes together and orders them from lowest metric at the top of the group to highest metric at the bottom of the group. If you add a new route with the same destination and metric as a route already in the table, MSS places the new route at the top of the group of routes with the same metric.

MSS can use a route only if the route is resolved through an IP interface on one of VLANs on the WX switch.