Industrial 4g lte router’s static routing failure trouble shooting

1.Static routing and class look up

When a routing table process checks for a resolvable static route that uses an intermediate address (an IP address in the routing table that is a reference to the next hop) , the check is always done in a categorical fashion, remove the static route whether or not using the IP classless command if the intermediate address in the route selection table can not be resolved by category.

Use Show IP route to see the routing table.

You can use debug to show that a network is down.

If no-class mode is used and a default route exists, backup-indicated routes with high management distance will never be loaded into the routing table when the primary static route fails. This is because any static route, even to a non-existent intermediate address, is resolved using the default route.

The E-lins routing table process calls a static routing function to check the routing table every 60 seconds to install or remove a static route based on a dynamically changing routing table.

2. Static routing and intermediate addresses

Static routing can be created using an intermediate network address or an outgoing interface. In most cases, it is more efficient to use the outgoing interface to resolve static routes in the routing table process.

As long as an intermediate IP address can be resolved in the routing table, it does not have to be an actual next-hop router interface. Static network routing, such as intermediate addresses, must eventually be resolved to a route with an outgoing interface in the routing table.

Whenever the routing table process needs to be X. X. When the X. 0/24 network uses a static routing table entry, it also needs to resolve the intermediate address Y. Y. Y. Y, called recursive lookup. An additional route lookup may have little impact on the performance of the routing process. However, taking multiple recursive lookups to obtain a resolved static route can affect performance.

3. Static routing optimization

To avoid recursive lookup: serial network: use the outgoing interface

Ethernet: uses both an intermediate address and an outgoing interface

4. Repeated static route installs and deletes

Use outgoing interfaces instead of intermediate addresses whenever possible to configure static routing.

5. Use discards

Sometimes a loop is created in the network. By periodically looking at the counters on the router interface, you can see the result of the routing loop.