Removing a system from the sysplex means that:
- All XCF group members in the sysplex know that the system is being
removed, so they can perform any necessary cleanup processing.
- All I/O to sysplex-shared resources is completed, to ensure data
integrity.
- All signaling paths are configured to a desired state (retained
or not).
The following are the basic steps for removing a system
from a sysplex. For detailed instructions for the necessary steps,
see “Removing a z/OS® image
from a Sysplex” at http://www.ibm.com/systems/z/advantages/pso/removing.html.
- Use the VARY XCF command to remove a system from the sysplex.
You can remove the system temporarily or permanently.
To temporarily
remove a system from the sysplex, issue:
VARY XCF,system-name,OFFLINE,RETAIN=YES
With
RETAIN=YES (the default), MVS™ on
each remaining system in the sysplex retains the definition of the devices for the signaling
paths that connected to the removed system. Therefore, the removed
system can be re-IPLed into the sysplex or another system can be added
in its place, and MVS automatically
starts the signaling paths. Note that the last system removed from
the sysplex, remains defined to the sysplex couple data set.
To
permanently remove a system from the sysplex, issue:
VARY XCF,system-name,OFFLINE,RETAIN=NO
With
RETAIN=NO, MVS on each remaining
system stops the signaling paths connected to the removed system and
discards their definition. Therefore, you cannot re-IPL the system
into the sysplex.
- Reply to message IXC371D, which requests confirmation of the VARY
XCF command.
Message IXC101I then informs you that the system is
being removed.
- When the target system is in a wait state (issues message IXC220W
with a wait state code 0A2), issue a system reset. The reset must
be done after the wait state, to ensure the integrity of I/O to sysplex
shared I/O resources.
- Reply DOWN to message IXC102A to continue removing the system
from the sysplex.
After you reply, when the removal of the system
is complete, message IXC105I is issued.