When the coupling facility structure volatility state changes

This topic applies to coupling facility log streams only. The following coupling facility volatility state changes can occur, which may result in different reactions by system logger.

A coupling facility becomes volatile, or for a duplex-mode structure when the coupling facilities containing both structure instances become volatile.
A coupling facility becomes non-volatile, or for a duplex-mode structure when either coupling facility containing the structure instances becomes non-volatile.

Logger's behavior to the state change depends on:

The type of state change
The current duplexing environment for the log streams in the affected structures, and
The log stream and structure duplexing specifications from the LOGR couple data set and the CFRM policy.

Some of the environments may result in rebuild processing for the structure. For complete information about rebuild processing, see z/OS MVS Programming: Sysplex Services Guide.

Other environments may result in logger changing its duplexing method. Additionally, some of the environments may require no recovery nor duplexing changes by logger. See Selecting a method of duplexing coupling facility log data for additional details on log data duplexing specifications.