5190/5194 Modular Tape Subsystem Manual

Operating the Cartridge Tape Drive and ACL

5190/5194 Modular Tape Subsystem Manual—426878-002

4-54

Valid CONTROL Operations

The following table shows valid CONTROL operations for the modular tape subsystem:

For more information about the CONTROL procedure call, see the Guardian

Procedure Calls Reference Manual and the Guardian Programmer’s Guide.

Choosing Block Size

D30 and subsequent releases let you create much larger data records when writing to

tape: up to 56 kilobytes (KB). If, however, you want to create block sizes that can be

read by most NonStop Himalaya servers, tape drives, and control units, you should not

create data records larger than 32,767 bytes (32 KB minus 1 byte) in size.

For a detailed discussion of this limit as it relates to the BACKUP and RESTORE

utilities, see Using the BLOCKSIZE Option on page 4-40.

SETMODE Attributes

The SETMODE procedure call specifies four attributes of the 5190 and 5194 tape

drives. The system returns an error for any SETMODE parameters other than the

supported parameters.

•

SETMODE 66 sets the tape density. The 5190 and 5194 drives currently support

only one density setting:

Number Operation

2 Write file mark

3 Rewind and unload (wait)

5 Rewind and leave online (no wait)

6 Rewind and leave online (wait)

7 Forward space file

8 Backward space file

9 Forward space record

10 Backward space record

24 Force end of volume (valid only for labeled tape)

26 Immediate I/O completion (commit data to tape and report error in case of data loss)

Setting param1 Value

38000 bpi 8