VARY REL command


Release a previously acquired NCP:

>>-VARY-- --NET--,--REL--,--ID--=--ncp_name--------------------->

                               .-,--CDLINK--=--ACT-------.   
>--+------------------------+--+-------------------------+------>
   '-,--OWNER--=--host_name-'  '-,--CDLINK--=--+-ACT---+-'   
                                               '-INACT-'     

>--+--------------------------+--------------------------------><
   '-,--TYPE--=--+-GIVEBACK-+-'   
                 '-IMMED----'


Release a PU:

>>-VARY-- --NET--,--REL--,--ID--=--pu_name---------------------->

                               .-,--FINAL--=--NO------.   
>--+------------------------+--+----------------------+--------->
   '-,--OWNER--=--host_name-'  '-,--FINAL--=--+-NO--+-'   
                                              '-YES-'     

>--+-------------------+---------------------------------------><
   '-,--TYPE--=--IMMED-'

Abbreviations

Operand	Abbreviation
VARY	V
FINAL=YES	FINAL
TYPE=GIVEBACK	G or GIVEBACK
TYPE=IMMED	I or IMMED

When using an abbreviation in place of an operand, code the abbreviation exactly as shown in the table. For example, when coding the abbreviation for TYPE=IMMED, code only I or IMMED. Do not code TYPE=I.

Purpose

Use the VARY REL (release) command to release a previously acquired NCP or to release a physical unit attached by a nonswitched line to an NCP (regardless of whether the physical unit was previously acquired).

The VARY REL command is applied to a previously acquired NCP or physical unit attached to an NCP as part of a backup and recovery procedure in a multiple-domain network. A physical unit attached to an NCP can also be released as part of a switched network backup procedure in either a single- or multiple-domain network. The purpose of the VARY REL command is to relinquish ownership of the following resources:

NCP resources that are normally owned by another host (if the NCP was activated before being acquired)
All resources within an NCP, including the NCP itself (if the NCP was acquired without having been previously activated)
An individual physical unit and its logical units

Releasing resources within an NCP makes them unknown to VTAM® until the NCP is reacquired, and any active traces for subordinate lines are deactivated; releasing a physical unit makes it unusable by the releasing host and makes its logical units unknown until the physical unit is reacquired. Releasing an NCP that had not been previously active also results in deactivation of the NCP. (Here there is no functional difference between the VARY REL and VARY INACT commands.)

As part of a switched network backup procedure for NCP resources, the VARY REL command can be entered for a physical unit that was not previously acquired. The purpose of the VARY REL command is to make the physical unit's logical units unknown to VTAM so that a corresponding switched physical unit definition (representing the same physical device with a different physical unit name but with the same logical unit names) can be activated.

Operands

CDLINK

Applies only to an NCP being released. It specifies whether any active cross-domain links and link stations are to remain active (in the NCP, not with respect to VTAM) after they are released. That is, the CDLINK operand specifies whether VTAM is to send deactivation requests to cross-domain links and link stations when the internal representations of these resources are deactivated as part of the VARY REL command processing.

For an NCP that was activated before being acquired, the CDLINK operand is ignored. The NCP remains active after the VARY REL command completes. Even though VTAM considers such links and link stations to be inactive, the NCP still considers them to be owned by VTAM. Therefore, specifying CDLINK=ACT in an environment of shared link and link station ownership might provide no benefits (because the shared ownership prevents traffic disruption on the link), but could cost the ability of another host to become a shared owner (because the share count is one closer to its limit than it needs to be). It could also prevent the original host from acquiring and activating the link. See the z/OS Communications Server: SNA Network Implementation Guide for details of special considerations and cautions that might be applicable to deactivation of cross-domain links and link stations.

For an NCP acquired without having been previously activated, this option is effective only on the first command (whether VARY INACT or VARY REL) applied to the NCP. Any subsequent CDLINK specifications are ignored.

CDLINK=ACT: Specifies that active cross-domain links and link stations are to remain active after they are released, so that sessions routing information through the NCP over such links can continue without disruption.
CDLINK=INACT: Specifies that cross-domain links and link stations within the scope of the release are to be deactivated as part of the NCP release processing. Any session traffic over such links might be disrupted (depending on whether such links and link stations are also owned by some other host). See the z/OS Communications Server: SNA Network Implementation Guide for information about how shared ownership affects the results of deactivating a link or link station.

FINAL

Specifies whether the physical unit specified on the ID operand will be reactivated.

FINAL=YES: Specifies that there are no immediate plans to reactivate the physical unit. The actual effects of this operand are device-dependent, and could include such functions as automatic power-off. See the appropriate component's document for the specific effects of a DACTPU type hex 01 command on a particular device. For physical units in a local SNA or switched major node, FINAL is meaningful only if the physical unit is fully active before deactivation begins.
FINAL=YES is ignored for type 2.1 physical units if ACTPU is not sent.
FINAL=NO: Specifies that there are plans to reactivate the physical unit.

ID=name

Specifies the name of the NCP or physical unit to be released.

OWNER=host_name

Specifies that the command is to apply only to resources defined with the OWNER operand, and whose owning SSCP matches the host_name specified in the command. host_name cannot be the name of the VTAM host from which you are issuing this command.

TYPE

Specifies the type of release. If neither GIVEBACK nor IMMED is specified, normal release occurs. Normal release does not break existing sessions, but does prevent the establishment of new sessions with nodes within the scope of this command.

TYPE=GIVEBACK

Applies only to an NCP and specifies that all subordinate resources that are capable of nondisruptive deactivation are to be released without disruption to existing LU-LU sessions.

Note: Because GIVEBACK is supported only at the line level, a normal release is performed for the following resources:

Lines attached to this NCP that are not capable of nondisruptive deactivation
PUs that are attached to a line that is not being released

TYPE=IMMED

Specifies immediate release. If you specify TYPE=IMMED, sessions involving the resources being released are disrupted.

You can specify TYPE=IMMED on a VARY REL command entered while a normal or giveback release is in progress.