How give only a read access to a range of volumes ?

Document ID : KB000016138
Last Modified Date : 14/02/2018
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Question:

Which is the method to protect either a volume, or range of volumes from being written to, and allow ONLY READ ACCESS.

 

 

Answer:

With RO47472 applied on TLMS 12.6 and TLMS 14.0 it is possible to benefit by defining a volume or a range of volumes to subpools identified as READONLY.

This option is useful for the following conditions:

  1. DR testing. 
  2. Conversions. 
  3. Obsolete tape media.

With this special subpool, volumes defined to a READONLY subpool are protected from 3 points of modification:

  1. Users cannot use a disposition of MOD to append to an existing dataset. 
  2. Secondary files cannot be added to a volume owned by this pool. 
  3. Output processing is prevented on volumes defined to this special pool.

Installation of the feature:

  1. Update CTAPOPTN - member CTOSCRxx. Add the following with the range of volumes you want to set to READONLY. 
    SCRPOOL=READONLYDR1,RANGE=000001-100000 (production range not to be used for output at DR) 
    SCRPOOL=READONLYOLD22,RANGE=C00001-C90000 (old media that you want to get rid of)
    SCRPOOL=READONLY3490,RANGE=900000-910000 (another old range that you don't want used for output)
  2. You will need to reload several CA-TLMS modules via CAS9.
    Modify the CAIRIMPARM with the following for TLMS 12.6

 PRODUCT (CA TLMS/-PRD) VERSION(TLC6) INIT(TLC6INIT) -

PARM(REINIT,LPA=ALL)

and
Modify the CAIRIMPARM with the following for TLMS 14

 PRODUCT(CA TLMS-PRD) VERSION(TLE0) INIT(TLE0INIT) -

PARM(REINIT,LPA=ALL)

 

 

3.    Attempt to MOD or add another file to a volume within the new READONLY subpool.