Use request type FENCE to prevent unintended access, through Soft
Fence, of a device, a set of devices in an LSS or all devices in an
LSS. This invokes ANTRQST ILK=PPRC REQUEST=FENCE.
- DEVN(dev)
- Specifies the device number to which the FENCE command is issued.
This device number must identify a CKD device defined to the host
system that is making the request. It is required.
- ACTION(action)
- Specifies an action to take. The values are FENCE or UNFENCE.
It is required.
- DVC(dvc)
- Indicates the binary logical unit number (LUN) for the device
to be fenced or unfenced. Required if you specify OPENDVCS(YES) and
SCOPE(DEV); ignored otherwise.
- LSS(lss)
- Specifies the binary logical subsystem number for the FB device
to be fenced or unfenced. Required if you specify OPENDVCS(YES);
ignored otherwise.
- MASK(mask)
- Specifies a 32-byte mask, each bit of which represents a device
on which to perform a soft fence operation. Bit 0 of the first byte
represents device 0. Bit 7 of the last byte represents device 255.
MASK is required when you specify SCOPE(MASK). Otherwise, it is ignored.
- OPENDVCS(NO | YES)
- Indicates if the request is for Open System (fixed block) devices.
- NO
- The device specified with DEVN is a CKD devices. This is the default.
- YES
- The request applies to an Open System LSS or device.
- SCOPE(scope)
- Specifies the scope of the fence operation. The values are:
- DEV
- The specified device only. This is the default.
- LSS
- All devices in the LSS of the device specified in the DEVN keyword
or the LSS keyword if OPENDVCS(YES).
- MASK
- All devices specified by the MASK keyword. You must also specify
MASK(mask) with a non-zero mask.
- SUBCHSET(subchset | 0)
- Specifies the subchannel set in which the command is to be issued.
The subchannel set where the I/O will be issued is the subchannel
set as defined in the Hardware Configuration Dialog (HCD). The valid
values are determined by what is supported by the host system's processor
and configured for the device.
If you omit the parameter, the command
is issued to the device that is logically in subchannel set 0. If
a swap has occurred, this could be the device that was defined in
an alternate subchannel set in the I/O configuration (IODF), with
HCD.