Using CSQ6ARVP

Use CSQ6ARVP to establish your archiving environment.

The default parameters for CSQ6ARVP, and whether we can alter each parameter using the SET ARCHIVE command, are shown in Table 10. If you need to change any of these values, refer to the detailed descriptions of the parameters. Planning your archive storage is discussed in the WebSphere MQ for z/OS Concepts and Planning Guide.

Table 10. Default values of CSQ6ARVP parameters
Parameter Description Default value SET command
ALCUNIT Units in which primary and secondary space allocations are made. BLK (blocks) X
ARCPFX1 Prefix for first archive log data set name. CSQARC1 X
ARCPFX2 Prefix for second archive log data set name. CSQARC2 X
ARCRETN The retention period of the archive log data set in days. 9999 X
ARCWRTC List of route codes for messages to the operator about archive log data sets. 1,3,4 X
ARCWTOR Whether to send message to operator and wait for reply before trying to mount an archive log data set. YES X
BLKSIZE Block size of archive log data set. 28 672 X
CATALOG Whether archive log data sets are cataloged in the ICF. NO X
COMPACT Whether archive log data sets should be compacted. NO X
PRIQTY Primary space allocation for DASD data sets. 4 320 X
PROTECT Whether archive log data sets are protected by ESM profiles when the data sets are created. NO X
QUIESCE Maximum time, in seconds, allowed for quiesce when ARCHIVE LOG with MODE(QUIESCE) specified. 5 X
SECQTY Secondary space allocation for DASD data sets. See the ALCUNIT parameter for the units to be used. 540 X
TSTAMP Whether the archive data set name should include a time stamp. NO X
UNIT Device type or unit name on which the first copy of archive log data sets is stored. TAPE X
UNIT2 Device type or unit name on which the second copy of archive log data sets is stored. Blank X

ALCUNIT

Specifies the unit in which primary and secondary space allocations are made.

Specify one of:

CYL

Cylinders

TRK

Tracks

BLK

Blocks

You are recommended to use BLK because it is independent of the device type.

The default is BLK.

If free space on the archive DASD volumes is likely to be fragmented, you are recommended to specify a smaller primary extent and allow expansion into secondary extents. For more information about space allocation for active logs, refer to the WebSphere MQ for z/OS Concepts and Planning Guide.

ARCPFX1

Specifies the prefix for the first archive log data set name.

See the TSTAMP parameter for a description of how the data sets are named and for restrictions on the length of ARCPFX1.

This parameter cannot be left blank.

The default is CSQARC1.

You might need to authorize the userid associated with the WebSphere MQ queue manager address space to create archive logs with this prefix.

ARCPFX2

Specifies the prefix for the second archive log data set name.

See the TSTAMP parameter for a description of how the data sets are named and for restrictions on the length of ARCPFX2.

This parameter cannot be blank even if the TWOARCH parameter is specified as NO.

The default is CSQARC2.

You might need to authorize the userid associated with the WebSphere MQ queue manager address space to create archive logs with this prefix.

ARCRETN

Specifies the retention period, in days, to be used when the archive log data set is created.

The parameter must be in the range zero through 9999.

The default is 9999.

Suggested settings:

Test system 3

In a test system, archive logs are probably not required over long periods.

Production system 9 999 (default)

Set this value high to effectively switch automatic archive log deletion off.

Discarding archive log data sets is discussed in the WebSphere MQ for z/OS System Administration Guide.

ARCWRTC

Specifies the list of z/OS routing codes for messages about the archive log data sets to the operator. This field is ignored if ARCWTOR is set to NO.

Specify up to 14 routing codes, each with a value in the range 1 through 16. You must specify at least one code. Separate codes in the list by commas, not by blanks.

The default is the list of values: 1,3,4.

For more information about z/OS routing codes, see the MVS Routing and Descriptor Codes manual.

ARCWTOR

Specifies whether a message is to be sent to the operator and a reply is received before attempting to mount an archive log data set.

Other WebSphere MQ users might be forced to wait until the data set is mounted, but they are not affected while WebSphere MQ is waiting for the reply to the message.

Specify either:

YES

The device needs a long time to mount archive log data sets. For example, a tape drive.

NO

The device does not have long delays. For example, DASD.

The default is YES.

Suggested settings:

Test system NO
Production system YES (default)

This is dependent on operational procedures. If tape robots are used, NO might be more appropriate.

BLKSIZE

Specifies the block size of the archive log data set. The block size you specify must be compatible with the device type you specify in the UNIT parameter.

The parameter must be in the range 4 097 through 28 672. The value you specify is rounded up to a multiple of 4 096.

The default is 28 672.

This parameter is ignored for data sets that are managed by the storage management subsystem (SMS).

If the archive log data set is written to DASD, you are recommended to choose the maximum block size that allows 2 blocks for each track. For example, for a 3390 device, you should use a block size of 24 576.

If the archive log data set is written to tape, specifying the largest possible block size improves the speed of reading the archive log.

Suggested settings:

Test system 24 576 (6 log records for each block)

This is the optimum block size for 3390 DASD.

Production system 28 672 (the maximum allowed; 7 log records for each block)

Use the highest possible block size for optimum tape I/O efficiency.

CATALOG

Specifies whether archive log data sets are cataloged in the primary integrated catalog facility (ICF) catalog.

Specify either:

NO

Archive log data sets are not cataloged

YES

Archive log data sets are cataloged

The default is NO.

All archive log data sets allocated on DASD must be cataloged. If you archive to DASD with the CATALOG parameter set to NO, message CSQJ072E is displayed each time an archive log data set is allocated, and WebSphere MQ catalogs the data set.

Suggested settings:

Test system YES
Production system NO (default)

COMPACT

Specifies whether data written to archive logs is to be compacted. This option applies only to a 3480 or 3490 device that has the improved data recording capability (IDRC) feature. When this feature is turned on, hardware in the tape control unit writes data at a much higher density than normal, allowing for more data on each volume. Specify NO if you do not use a 3480 device with the IDRC feature or a 3490 base model, with the exception of the 3490E. Specify YES if you want the data to be compacted.

Specify either:

NO

Do not compact the data sets

YES

Compact the data sets

The default is NO.

Specifying YES adversely affects performance. Also be aware that data compressed to tape can be read only using a device that supports the IDRC feature. This can be a concern if you have to send archive tapes to another site for remote recovery.

Suggested settings:

Test system Not applicable
Production system NO (default)

This applies to 3480 and 3490 IDR compression only. Setting this to YES might degrade archive log read performance during recovery and restart; however, it does not affect writing to tape.

PRIQTY

Specifies the primary space allocation for DASD data sets in ALCUNITs.

The value must be greater than zero.

The default is 4 320.

This value must be sufficient for a copy of either the log data set or its corresponding BSDS, whichever is the larger. To determine the necessary value, follow this procedure:

  1. Determine the number of active log records actually allocated (

    c) as explained in Task 14: Create the bootstrap and log data sets.

  2. Determine the number of 4096-byte blocks in each archive log block:

        d = BLKSIZE / 4096   

    where BLKSIZE is the rounded up value.

  3. If ALCUNIT=BLK:

        PRIQTY = INT(c / d) + 1    

    where INT means round down to an integer.

    If ALCUNIT=TRK:

        PRIQTY = INT(c / (d * INT(e/BLKSIZE))) + 1   

    where e is the number of bytes for each track (56664 for a 3390 device) and INT means round down to an integer.

    If ALCUNIT=CYL:

        PRIQTY = INT(c / (d * INT(e/BLKSIZE) * f)) + 1    

    where f is the number of tracks for each cylinder (15 for a 3390 device) and INT means round down to an integer.

For information about how large to make your log and archive data sets, see Task 14: Create the bootstrap and log data sets and Task 15: Define your page sets.

Suggested settings:

Test system 1 680

Sufficient to hold the entire active log, that is:

10 080 / 6 = 1 680 blocks
Production system Not applicable when archiving to tape.

If free space on the archive DASD volumes is likely to be fragmented, you are recommended to specify a smaller primary extent and allow expansion into secondary extents. For more information about space allocation for active logs, refer to the WebSphere MQ for z/OS Concepts and Planning Guide.

PROTECT

Specifies whether archive log data sets are to be protected by discrete ESM (external security manager) profiles when the data sets are created.

Specify either:

NO

Profiles are not created.

YES

Discrete data set profiles are created when logs are off-loaded. If you specify YES:

  • ESM protection must be active for WebSphere MQ.

  • The user ID associated with the WebSphere MQ queue manager address space must have authority to create these profiles.

  • The TAPEVOL class must be active if you are archiving to tape.

Otherwise, off-loads will fail.

The default is NO.

QUIESCE

Specifies the maximum time in seconds allowed for the quiesce when an ARCHIVE LOG command is issued with MODE(QUIESCE) specified.

The parameter must be in the range 1 through 999.

The default is 5.

SECQTY

Specifies the secondary space allocation for DASD data sets in ALCUNITs. The secondary extent can be allocated up to 15 times; see the z/OS MVS JCL Reference and z/OS MVS JCL User's Guide for details.

The parameter must be greater than zero.

The default is 540.

TSTAMP

Specifies whether the archive log data set name has a time stamp in it.

Specify either:

NO

Names do not include a time stamp. The archive log data sets are named:

arcpfxi.Annnnnnn

Where arcpfxi is the data set name prefix specified by ARCPFX1 or ARCPFX2. arcpfxi can have up to 35 characters.

YES

Names include a time stamp. The archive log data sets are named:

arcpfxi.cyyddd.Thhmmsst.Annnnnnn
where c is 'D' for the years up to and including 1999 or 'E' for the year 2000 and later, and arcpfxi is the data set name prefix specified by ARCPFX1 or ARCPFX2. arcpfxi can have up to 19 characters.

EXT

Names include a time stamp. The archive log data sets are named:

arcpfxi.Dyyyyddd.Thhmmsst.Annnnnnn

Where arcpfxi is the data set name prefix specified by ARCPFX1 or ARCPFX2. arcpfxi can have up to 17 characters.

The default is NO.

UNIT

Specifies the device type or unit name of the device that is used to store the first copy of the archive log data set.

Specify a device type or unit name of 1 through 8 alphanumeric characters. The first character must be alphabetic.

This parameter cannot be blank.

The default is TAPE.

If you archive to DASD, we can specify a generic device type with a limited volume range.

If you archive to DASD:

  • Make sure that the primary space allocation is large enough to contain all the data from the active log data sets.

  • Make sure that the archive log data set catalog option (CATALOG) is set to YES.

  • The archive log data sets cannot extend to another volume.

If you archive to TAPE, WebSphere MQ can extend to a maximum of 20 volumes.

Suggested settings:

Test system DASD
Production system TAPE

For more information about choosing a location for archive logs, refer to the WebSphere MQ for z/OS Concepts and Planning Guide.

UNIT2

Specifies the device type or unit name of the device that is used to store the second copy of the archive log data sets.

Specify a device type or unit name of 1 through 8 alphanumeric characters. The first character must be alphabetic. If this parameter is blank, the value set for the UNIT parameter is used.

The default is blank.