Best Practices Upgrading a Coupling Facility Version 2
Document Author: Additional Author(s):
David H Surman, Neil Johnson
WSC IBM Z
# 2094; # 2096; # 2097; # 2098
Abstract: Planning for an upgrade of a parallel sysplex to z196 or z114 or an upgrade which requires a POR? Need to install maintenance which requires a coupling facility to be reactivated? This paper documents the best practices for installing a new CF, doing a POR of a CEC with a coupling facility image on it and reactivating a coupling facility image. IBM strongly recommends that the best practices be followed to prevent unplanned down time, other adverse impacts to applications and minimize the maintenance upgrade window.
Version 2 of the Best Practices: Upgrading a Coupling Facility procedures simplify the removal of the last coupling facility link which is also the last timing link, or ensure STP timing will not be disrupted. Version 2 procedures have been updated to use the CF SHUTDOWN command instead of the DEACTIVATE command. SHUTDOWN is safer as it will not complete if there are still structures in the coupling facility. SHUTDOWN was specifically added to avoid a sysplex outage as a result of the incorrect coupling facility being DEACTIVATEd. Finally, with the understanding of time constraints during upgrades a streamlined procedure was added for the specific situation of a POR of a CPC on which a coupling facility resides with no physical or logical changes to the coupling facility.