MAXTAPES—Limit the Number of Tape Mounts

The MAXTAPES keyword specifies the maximum number of tapes per tablespace copy merge.
cafrdb2
The MAXTAPES keyword specifies the maximum number of tapes per tablespace copy merge. Use this keyword to limit the number of tape mounts that are performed.
For example, you perform a RECOVER that uses one full image copy and two incremental image copies. MAXTAPES is set to 2 (in the RECOVER syntax or in parmlib), and all image copies are on tape. The recovery uses only the full image copy and one incremental image copy. Log records are applied starting with the STARTRBA of the incremental image copy.
Review the following considerations:
  • If you specify several tablespaces in one RECOVER statement, the MAXTAPES value is applied
    per tablespace
    during the recovery.
  • MAXTAPES is not valid with REBUILD INDEX.
This keyword has the following format:
MAXTAPES
int
  • int
    Specifies the maximum number of tapes per tablespace copy merge.
    Default:
    5
    Limits:
    1 - 32
Example: MAXTAPES
Assume that your system is configured with eight tape drives. You must recover five tablespaces, but you want to leave some tape drives available for other users. You also want to recover the tablespaces concurrently. The following recovery scenario uses one tape drive per tablespace, for a total of five tape drives. Three tape drives remain available for use by other programs.
Use the following syntax for this situation:
RECOVER TABLESPACE XX.YY TABLESPACE AA.BB TABLESPACE CC.DD TABLESPACE EE.FF TABLESPACE GG.HH MAXTAPES 1 SORTLOG YES
If you specify SORTLOG with incremental copies that reside on tape, and your job recovers more than one tablespace per task, then all tablespaces but the first one invoke an error message. This message states that separate recoveries are required when the job must mount the incremental copies. This error occurs because
Fast Recover
mounts the image copies for the first tablespace before reading the log records.
You can solve this problem by defining a different MAXTAPES value. If you recover three tablespaces with MAXTASKS 1 and MAXTAPES 1, and the tablespaces have incremental copies, the first tablespace is recovered. An error occurs on the second one. However, if you set MAXTAPES to 3 in this example, the job completes successfully because each tablespace is the first tablespace in a task.