Considerations Some issues must be carefully considered when deciding to implement a static routing environment: The only way to remove static routes from the routing table is for the network administrator to update the routing table. If a destination (sub)network becomes unreachable, the static routes for that (sub)network will remain in the routing table, and packets will still be forwarded to the destination. The routing table's management is manual, increasing the possibilities of outages caused by definition errors. 5.4.2 Design scenario 2: OSPF routing with OMPROUTE The most common and recommended way to use dynamic routing in the z/OS environment is to define the stack as a OSPF Stub Area or even better as a Totally Stubby Area. Stub Areas minimize storage and CPU processing at the nodes that are part of the Stub Area because they maintain less knowledge about the topology of the Autonomous System (AS) than do other types of non-backbone routers. They maintain knowledge only of intra-area destinations--summaries of inter-area destinations and default routes within the AS in order to reach external destinations. A Totally Stubby Area receives less routing information than a Stub Area. It only knows of intra-area destinations and default routes within the Stub Area to reach external destinations. Our OSPF scenario is represented by Figure 5-4 on page 159.