The storage system is configured with one Storage Subsystem ID (SSID) for each group of 64 or 256 devices to provide one or four SSIDs per CU image. Each SSID must be unique inside the individual array and also for the entire storage system. This includes across all LPARs in a sysplex. SSIDs are user-specified and are assigned during storage system installation in hexadecimal format, from 0004 to FEFF.
CAUTION:
- For the SSID of an LDEV used by mainframe hosts, set a value in the range specified as SSID requirements. If you set a value outside the specified range, mainframe hosts might not be able to use the LDEV.
- When you create an open-system volume using VSP One Block Administrator or VSP Block Storage REST API, an unused SSID is automatically assigned. However, If both mainframe-system volumes and open-system volumes are operated on the same storage system, and you create the open-system volume using VSP One Block Administrator or VSP Block Storage REST API, set the SSID in advance to prevent the SSID used by a mainframe-system volume from being automatically assigned to the open-system volume. You can set the SSID in advance by specifying the -ssid option for the raidcom modify ldev command in CCI. For details, see the Command Control Interface Command Reference.
This table shows the relationship between controller emulation type and SSID.
| Controller emulation type | SSID requirement | Virtual LVI support |
|---|---|---|
| I-2107 | 0004 to FEFF | 3390-3, 3390-3A, 3390-3B, 3390-3C, 3390-9, 3390-9A, 3390-9B, 3390-9C, 3390-L, 3390-LA, 3390-LB, 3390-LC, 3390-M, 3390-MA, 3390-MB, 3390-MC volumes |