Dell PowerConnect Brocade 300 Fabric OS Administrator's Guide v7.1.0 - Page 349

Traffic Isolation Zoning overview 12 FSPF routing rules and traffic isolation All traffic must use the lowest cost path. FSPF routing rules take precedence over the TI zones, as described in the following situations. If the dedicated ISL is not the lowest cost path ISL, then the following rules apply: • If failover is enabled, the traffic path for the TI zone is broken, and TI zone traffic uses the lowest cost path instead. • If failover is disabled, the TI zone traffic is blocked. If the dedicated ISL is the only lowest cost path ISL, then the following rules apply: • If failover is enabled, non-TI zone traffic as well as TI zone traffic uses the dedicated ISL. • If failover is disabled, non-TI zone traffic is blocked because it cannot use the dedicated ISL, which is the lowest cost path. For example, in Figure 33, there is a dedicated path between Domain 1 and Domain 3, and another, non-dedicated, path that passes through Domain 2. If failover is enabled, all traffic will use the dedicated path, because the non-dedicated path is not the shortest path. If failover is disabled, non-TI zone traffic is blocked because the non-dedicated path is not the shortest path. Domain 1 8 1 9 3 Domain 3 9 14 12 15 = Dedicated Path 16 = Ports in the TI zone Domain 2 FIGURE 33 Dedicated path is the only shortest path 7 6 5 Domain 4 In Figure 34 on page 350, a dedicated path between Domain 1 and Domain 4 exists, but is not the shortest path. In this situation, if failover is enabled, the TI zone traffic uses the shortest path, even though the E_Ports are not in the TI zone. If failover is disabled, the TI zone traffic stops until the dedicated path is configured to be the shortest path. Fabric OS Administrator's Guide 349 53-1002745-02