TMSCP SERVE ALL

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TMSCP_SERVE_ALL is a bitmask system parameter that controls the serving of tapes. The settings take effect when the system boots. You cannot change the settings when the system is running.

Starting with OpenVMS Version 7.2, the serving types are implemented as a bit mask. To specify the type of serving your system will perform, locate the type you want in the following table and specify its value. For some systems, you may want to specify two serving types, such as serving all tapes except those whose allocation class does not match. To specify such a combination, add the values of each type, and specify the sum.

In a mixed-version cluster that includes any systems running OpenVMS Version 7.1-x or earlier, serving all available tapes is restricted to serving all tapes except those whose allocation class does not match the system's allocation class (pre-Version 7.2 meaning). To specify this type of serving, use the value 9, which sets bit 0 and bit 3. The following table describes the serving type controlled by each bit and its decimal value:

Bit Value When Set Description
0 1 Serve all available tapes (locally attached and those connected to HSx and DSSI controllers). Tapes with allocation classes that differ from the system's allocation class (set by the ALLOCLASS parameter) are also served if bit 3 is not set.
1 2 Serve locally attached (non-HSx and non-DSSI) tapes.
2 N/A Reserved
3 8 Restrict the serving specified by bit 0. All tapes except those with allocation classes that differ from the system's allocation class (set by the ALLOCLASS parameter) are served. This is pre-Version 7.2 behavior. If your cluster includes systems running OpenVMS Version 7.1-x or earlier, and you want to serve all available tapes, you must specify 9, the result of setting this bit and bit 0.

Although the serving types are now implemented as a bit mask, the values of 0, 1, and 2, specified by bit 0 and bit 1, retain their original meanings:

0 Do not serve any tapes (the default for earlier versions of OpenVMS)
1 Serve all available tapes
2 Serve only locally attached (non-HSx and non-DSSI) tapes

If the TMSCP_LOAD system parameter is 0, TMSCP_SERVE_ALL is ignored.