Shared Tape Allocation Manager (STAM) Facility › Defining the STAM Parameter File › DEV Entries › Continuing DEV Entries › Preferred Drives

Preferred Drives

The following code shows sample DEV entries for dedicated, preferred, and not available tape drives.

Sample DEV Entries

SYS1,VMT2,VMT3
T80 DEV (180,D1),180,(180,P4)
T81 DEV (181,D1),180,(181,P4)
T82 DEV (182,P2),182,(182,P4)
.
T87 DEV (187,P2),187,(187,P4)
*
T90 DEV (390,P3),(390,P1),(390,P3)
.
T97 DEV (397,P3),(397,P1),(397,P3)
*
T60 DEV (560,P4),560,(560,P2)
.
T65 DEV (565,P4),565,(565,P2)
T66 DEV (566,P4),566,(566,D1)
T67 DEV (567,P4),567,(567,D1)
T70 DEV (670,N5),670,(670,N5)
T71 DEV (671,N5),671,(671,N5)

On system SYS11, the 180 devices are used first, then the 390s, then the 560s. On system VMT3, the 560 devices are the first preference, followed by the 390s and the 180s. System VMT2 uses the 390 devices first and then devices from the other two groups. Because the dedicated devices have a higher preference specified, they are allocated before any of the other devices.

You can also specify preference for devices marked not available. The preference values take effect when the devices are varied available.

The following rules apply:

• If no preference is specified, the least preferred (9) is assumed.
• If only the character "P" is specified, the most preferred (1) is assumed.
• Unless otherwise specified, dedicated devices are preferred above all other groups.