New or Modified HSC/VTCS Commands

ELS 7.2 includes the following new or modified HSC/VTCS commands:

These updates supersede the information found in the existing ELS Command, Control Statement, and Utility Reference.

CONFIg GLOBAL

This update applies to:

ELS 7.2 Command, Control Statement, and Utility Reference

Chapter 3, HSC Commands, Utilities, and Control Statements

Summary:

The VTCS CONFIg GLOBAL statement adds the VTVCHAIN parameter.

Description

The CONFIg GLOBAL statement specifies VTCS global values. This statement is required.

Syntax

The following figure shows the VTCS CONFIg GLOBAL command syntax:

Figure 2-1 CONFIg GLOBAL Command Syntax

Description of "Figure 2-1 CONFIg GLOBAL Command Syntax"

Parameters

The VTCS CONFIg GLOBAL command includes the following parameters:

MAXVTV=nnnnnn

optionally, specifies the maximum number of VTVs that can be migrated to a single MVC.

nnnnnn indicates the number of VTVs. Valid values include:

4 to 32000 for a D, E or F level CDS
4 to 65000 for a G level CDS

MVCFREE=nnnn

optionally, specifies the minimum number of free MVCs in the MVC pool. A free MVC has 100% usable space and does not contain any migrated VTVs. Valid values are 0 to 255. The default is 40.

If free MVCs is equal or less than this value, VTCS issues message SLS6616I and starts an automatic space reclamation.

Note:

If you set MVCFREE=0, VTCS actually uses the default value (40).

VTVattr

optionally, specifies when VTCS assigns a Management Class to a VTV.

SCRATCH: Assign a Management Class only when VTCS does a scratch mount of the VTV (the default).
ALLmount: Assign a Management Class whenever VTCS mounts the VTV.

Caution:
If you specify that VTCS assigns a Management Class whenever VTCS mounts a VTV, these attributes can change, which can cause undesirable or unpredictable results.
For example, if an application writes data set PROD.DATA to VTV100 with a Management Class of PROD, then writes data set TEST.DATA to VTV100 with a Management Class of TEST, then the VTV (and both data sets) has a Management Class of TEST. Similarly, it is possible to write TAPEREQ statements or SMS routines that assign different Management Classes to the same data set (for example, based on job name), which can also cause a VTV’s Management Class to change.

RECALWER

optionally, specifies whether VTCS recalls VTVs with read data checks (applies to recall and drain operations).

YES: Recall VTVs with read data checks (the default).
NO: Do not recall VTVs with read data checks.

LOCKSTR=structure-name

optionally, specifies the Coupling Facility Structure that holds VTCS Lock Data.

structure-name indicates the coupling facility structure. It must be 16 characters or less and conform to IBM’s standard for naming Coupling Facility Structures. Refer to Oracle’s ELS publication Installing ELS for more information.

Caution:

CONFIG RESET is required to add LOCKSTR=structure-name to a CDS that did not previously use LOCKSTR=structure-name and to remove LOCKSTR=structure-name from a CDS. CONFIG RESET is not required to change lock structure names (for example, going from LOCKSTR=VTCSL1 to LOCKSTR=VTCSL2).

REPlicat

optionally, specifies when VSM replicates the VTV.

ALWAYS

The replicate request is added to the VTCS replication queue every time the VTV is dismounted, regardless of whether the VTV was changed while it was mounted (the default).

CHANGED

The replicate request is added to the VTCS replication queue if either of the following have occurred:

The VTV was changed while it was mounted.
The VTV was only read while mounted but less than the expected number of MVC copies of the VTV exist.

Once the expected number of MVC copies exist, replication does not occur.

Regardless of the CONFIG GLOBAL REPlicat setting, replication also requires that:

The VTV must be dismounted in a VTSS that supports replication and there cannot be an identical copy of the VTV in the other VTSS in the Cluster.
In addition to the CONFIG GLOBAL REPlicat value, you must specify REPlicat(YES) on a VTV’s Management Class for replication to occur.

VTVPAGE

optionally, specifies the page size used to store VTV data in the VTSS and on the MVCs. This setting only applies to 400 and 800 MB VTVs. If VTVPAGE is not specified on either the MGMTclas statement or the CONFIG GLOBAL statement, the default is STANDard.

STANDARD

standard page size, which is compatible with all VSM3 or VSM4 models and microcode levels.

LARGE

large page size, which can provide improved performance within the VTSS and for migrates and recalls. Large page size requires a G level CDS. For more information on CDS levels, refer to the "CONFIg" command section in the ELS Command, Control Statement, and Utility Reference. For 2 and 4 GB VTVs (MAXVtvsz 2000 or 4000), a VTVPAGE setting of LARGE is always used.

VTVPAGE does not apply to VSM2s. VTVPAGE(LARGE) requires VSM4 or VSM5 microcode D02.02.00.00 or VSM3 microcode N01.00.77.00. No installed option is required.

MGMTCLAS VTVPAGE, if specified, overrides the CONFIG GLOBAL VTVPAGE value. If VTVPAGE is not specified on either the MGMTclas statement or the CONFIG GLOBAL statement, the default is STANDard.

Consider the following:

The page size of a VTV can only be changed by a VTV scratch mount. Additional restrictions may also apply for scratch VTVs that were previously resident in a VTSS.
If you specify LARGE and the CDS level or VTSS microcode do not support LARGE, VTCS issues warning messages and VTVPAGE defaults to STANDard.
If you specify STANDard for 2 or 4 GB VTVs VTCS issues warning messages and defaults to LARGE.
Creating VTVs with large pages makes these VTVs unreadable in configurations that do not support large VTV pages.

NLIBDRNR

optionally, specifies how VTCS handles non-library resident MVCs for drain or reclaim processing.

YES: VTCS requests the mount of the non-library MVC. This is the default.
NO: VTCS suppresses the mount and purges the request.

Note:

For reclaim, only library resident MVCs can be selected for processing, never non-library ones. However, between the time a library resident MVC is selected and the time it is actually processed, it may have become non-resident by being ejected.
For drain, non-library resident MVCs can be selected.

NLIBMIGR

optionally, specifies whether non-library resident MVCs will be selected for Migration processing.

YES: Allow non-library resident MVCs to be selected (default).
NO: Do not allow non-library resident MVCs to be selected.

NLIBRECL

optionally, specifies whether non-library resident MVCs will be selected for Recall processing.

YES: Allow non-library resident MVCs to be selected (default).
NO: Do not allow non-library resident MVCs to be selected.

MVCMNTTO=nn

optionally, specifies the value in minutes when a mount of an MVC will timeout.

nn indicates the time in minutes. Valid values are 5 to 30 minutes. The default is 15.

INITMVC

optionally, specifies whether un-initialized MVCs are to be initialized when they are first mounted.

NO: Un-initialized MVCs should not be initialized. This is the default.
YES: Un-initialized MVCs should be initialized.

SYNCHREP

optionally, specifies whether VTV synchronous replication feature is enabled.

NO: Synchronous replication is not enabled (the default).
YES: Synchronous replication is enabled.

Note:

SYNCHREP=YES only enables synchronous replication. To actually implement synchronous replication, you must create a Management Class that specifies REPLicat=YES_SYNC. For more information, refer to the "MGMTclas Control Statement" section in the ELS Command, Control Statement, and Utility Reference.

MAXRTDS

optionally, specifies the maximum number of RTDs supported.

16: up to 16 RTDs supported.
32: up to 32 RTDs supported.

FASTMIGR

optionally, specifies whether the stacked or streamed migrates feature is enabled for all VTSSs that support this feature.

STREAM: Specifies to use the streaming method for migrations. VTCS monitors responses from the RTD and uses them to decide as to when a VTV has become migrated. Full advantage is made of the buffer within the RTD to improve the throughput when performing migration.
This option also implies the use of the STACKED feature.
STACKED: Specifies to use the stacked method for migrations. VTCS maintains a small queue of requests to the VTSS. Advantage is made of the various buffers in the VTSS and RTD to improve the throughput when performing a migration. For backward compatibility, the value YES is the equivalent of STACKED.
NO: Disable stacked migrates (the default).

FASTMIGR=STREAM or STACKED has the following prerequisites:

FASTMIGR=STACKED: VSM4/VSM5 microcode D02.05.00.00 or higher. If this level of microcode is not installed on all VTSSs in the configuration, Stacked Migration will be limited to the VTSSs that have it installed.
FASTMIGR=STREAM: VSM4/VSM5 microcode D02.15.xx.00 or higher. If this level of microcode is not installed on all VTSSs in the configuration, Streamed Migration will be limited to the VTSSs that have it installed.
ELS 7.0 or higher with PTFs.
CDS level G or higher.
FICON ports for FICON RTDs and CLINKs.

For the Stacked Migration feature to be enabled, all hosts must be running the prerequisites, otherwise:

If a host is active and does not support or tolerate stacked migrates, then the CONFIg utility returns an error.
If a host is started and does not support or tolerate this feature, then the host shuts down.

LOGPOL

optionally, specifies whether VTCS CDS logging is optional or required.

OPTional

Logging is optional. This is the default. This mode is required for configurations that include 7.1, 7.2, and lower level hosts.

REQuired

Logging is enabled for all events on all hosts that share the CDS. This requires all hosts to be at level 7.0 or higher. The following events are logged:

new version of VTV
imported VTV
first use or reuse of an MVC
imported MVC
add VTV to MVC
VTV on an imported MVC
unlink VTV from MVC
reclaim VTV from MVC
reset MVC EOT backward
electronic export of VTV

MAXVTVSZ

optionally, specifies a default maximum compressed VTV size (MB) that may be used during the creation of VTVs. Valid values for this parameter depend on both the CDS level and the microcode levels of the applicable VTSSs.

400: 400MB. This is the default.
800: 800MB. The CDS must be at E level or above.
2000: 2GB. The CDS must be at G level or above.
4000: 4GB. The CDS must be at G level or above.
32000: 32 GB. The CDS must be at I level.

Considerations:

The size of a VTV changes only after it goes through a scratch cycle. Therefore, if you change the Management Class and DISP=MOD, then it will still retain the original size.
If you specify a VTV size that is not supported by the configuration, VTCS issues warning messages and MAXVtvsz defaults to the largest VTV size supported by the configuration.
MAXVtvsz does not apply to VSM2s.
MAXVTVSZ(2000) or MAXVTVSZ(4000) requires VSM4 or VSM5 microcode D02.02.00.00 or VSM3 microcode N01.00.77.00. No installed option is required.
MAXVTVSZ(32000) requires VSM6 minimum microcode level 6.2 and VLE minimum microcode level 1.5.1, if VLE is in the configuration.

The CONFIg GLOBAL and MGMTCLAS MAXVTVSZ parameters interact as follows:

If MAXVTVSZ is specified on MGMTCLAS, this value overrides the CONFIg GLOBAL MAXVTVSZ value.
If MAXVTVSZ is not specified on MGMTCLAS, the CONFIg GLOBAL MAXVTVSZ value, if specified, is used. Otherwise, MAXVTVSZ defaults to 400MB.
If MAXVTVSZ is not specified on MGMTCLAS or on CONFIg GLOBAL, MAXVTVSZ defaults to 400MB.

LOCKTOUT=nnn

optionally, specifies the minimum number of minutes that a resource is locked before message SLS6946E is issued.

nnn indicates the number of minutes. Valid values are 0, or any value between 5 and 240. If 0 is specified, message SLS6946E will not be issued when a required resource is locked. If this parameter is not specified, the current default of 10 minutes is retained.

Note:

LOCKTOUT is only supported at ‘F’ level CDS (V61ABOVE) and above.

FASTRECL

Optionally specifies whether VTCS should perform Early Time to First Byte (ETTFB), also known as concurrent tape recall/mount, for all VTSSs that support the feature. This parameter applies to recalls from RTDs and recalls from VLE.

NO: Disable the ETTFB feature. This is the default.
YES: Enable the ETTFB feature. If you globally enable this feature, you can disable it for individual VTSSs through the CONFIg VTSS NOERLYMT parameter. Refer to the "CONFIg VTSS Statement" section in the ELS Command, Control Statement, and Utility Reference.

VTDGT256

Optionally, specifies whether greater than 256 VTDs are to be used.

NO: Specifies that only the first 256 VTDs will be used. The first 256 VTDs are on control unit 00 - 0F of the VTSS with VDID address of x0000 - x0F0F. NO is the default.
YES: Specifies that all configured VTDs in the VTSS can be used. This is only valid if the VTSS supports greater than 256 devices. The feature is globally enabled and applies to all VSMs that support greater than 256 devices. The feature can be disabled for an individual VTSS through the CONFIG VTSS NOGT256 parameter. Refer to "CONFIG VTSS NOGT256" in the ELS Command, Control Statement, and Utility Reference for more information.

Note:

VTDGT256 (YES) is only valid with VSM model 6 and above.

VTVCHAIN

optionally, specifies globally if VTCS VTV chaining is enabled for multi-volume datasets.

YES

VTV chaining for multi-volume datasets is enabled. This is the default.

NO

VTV chaining for multi-volume datasets is disabled. Recall look-ahead will not be performed.

Note:

VTV recall look-ahead will not be performed for any existing chained VTVs.
If a dataset is created while VTV chaining is disabled then the dataset's VTV chaining is disabled on all systems, even if the other system is running with VTV chaining enabled.

CONFIg HOST

This update applies to:

ELS 7.2 Command, Control Statement, and Utility Reference

Chapter 3, HSC Commands, Utilities, and Control Statements

Summary:

The VTCS CONFIg HOST statement adds the VTVCHAIN parameter.

Description

The CONFIg HOST statement is an optional statement that defines an MSP host and,optionally, the NOMIGRAT or NORECLAM parameters.

If specified, the HOST statement must follow the VTSS statement for the VTSS attached to that host. You must either specify all host definitions or none; if you specify only some hosts attached to a VTSS, VTCS issues an error.

Syntax

The following figure shows the VTCS CONFIg HOST command syntax:

Figure 2-2 CONFIg HOST Command Syntax

Description of "Figure 2-2 CONFIg HOST Command Syntax"

Parameters

The CONFIg HOST command includes the following parameters:

NAME=xxxx

specifies the LIBGENed host name. xxxx indicates the host name.

NOMIGRAT

optionally, specifies that this host cannot perform migrations, consolidations, or export by VTV or Management Class from the VTSS(s) that the host accesses. NOMIGRAT controls both automatic and demand migrations and consolidations.

Note:

Specifying NOMIGRAT also causes NORECLAM to be set.
IMMEDmig KEEP and IMMEDmig DELETE are mutually exclusive with CONFIG HOST NOMIGRAT. If you specify both, the IMMEDmig value overrides NOMIGRAT, and VTCS does not issue a message about this override.

NORECLAM

optionally, specifies that this host cannot initiate automatic or demand reclaim processing using the VTSS(s) that the host accesses. The host can still perform MVC drains using MVCDRain.

CMDCONN

optionally, specifies one of the following VTSS access methods:

CHANNEL: indicates ESCON or FICON channel access. This is the default.
TCPIP: indicates TCP/IP access. TCPIP requires a valid CONFIg VTSS IPCONN=(name-list) value.

VTVCHAIN

optionally, specifies locally if VTCS VTV chaining is enabled for multi-volume datasets. The VTVCHAIN parameter on the CONFIG HOST statement overrides the CONFIG GLOBAL VTVCHAIN parameter.

YES: VTV chaining for multi-volume datasets is enabled. This is the default.
NO: VTV chaining for multi-volume datasets is enabled. Recall look-ahead will not be performed.

Note:

VTV recall look-ahead will not be performed for any existing chained VTVs.
If if a dataset is created while VTV chaining is disabled then the dataset's VTV chaining is disabled on all systems, even if the other system is running with VTV chaining enabled.