IBM XIV Storage System Copy Services and Migration

the additional Fibre Channel ports are active. However, they are enabled as more modulesare added.The suggested host port to capacity ratios are shown in Table 8-6.Table 8-6 XIV host port ratio as capacity growsTotal XIV modulesCapacity allocatedto one SVC cluster (TB)XIV host portszoned to one SVC cluster6 27 49 43 810 50 811 54 1012 61 1013 66 1214 73 1215 79 12To use additional XIV host ports, run a cable from the SAN switch to the XIV and attach to therelevant port on the XIV patch panel. Then zone the new XIV host port to the SVC cluster viathe SAN switch. No commands must be run on the XIV.8.12 Understanding the SVC controller path valuesIf you display the detailed description of a controller as seen by SVC, for each controller hostport you will see a path value. Because each MDisk has a preferred XIV host port, thepath_count is the number of MDisks using that port multiplied by the number of SVC nodes(commonly 2 or 4). In Example 8-66 the SVC cluster has two nodes and can access six XIVvolumes (MDisks), so 6 volumes times 2 nodes means 12 paths. These 12 paths will bedistributed in a round-robin fashion across all accessible XIV host ports. Because in thisexample there are six XIV ports zoned to the SVC, there will be two paths per port.We can confirm is that the SVC is utilizing all six XIV interface modules. In Example 8-66 XIVinterface modules 4 through 9 are all clearly zoned to the SVC (because the WWPN ending in71 is from XIV module 7, the module with WWPN ending in 61 is from XIV module 6, and soon. To decode the WWPNs use the process described in 8.3.2, “Determining XIV WWPNs”on page 247.Example 8-66 Path count as seen by SVCIBM_2145:SVCSTGDEMO:admin> svcinfo lscontroller 2id 2controller_name XIVWWNN 5001738000510000mdisk_link_count 6max_mdisk_link_count 12degraded novendor_id IBMproduct_id_low 2810XIVproduct_id_highLUN-0274 IBM XIV Storage System: Copy Services and Migration