The PPRC support CU option allows you to specify whether the CU will generate sense information that is compatible with PPRC. This option is extremely important for TCz disaster recovery planning and must be set for each CU.
- If the host does not support PPRC, select No to configure the CU to report SIMs. The default is No.
- If the host system supports PPRC, select Yes to configure the CU to generate PPRC-compatible sense information when a TCz pair is suspended instead of a SIM. You must select Yes for each CU in the primary and secondary storage systems. If Yes is selected, the MCU will still report moderate- and serious-level SIMs, as well as DF40 and DF48 device SIMs. If you plan to utilize the CGROUP (FREEZE/RUN) command for TCz pairs, you must select Yes.
When you change the PPRC support option for the P-VOL, you do not need to split and resync the pair. When you change the PPRC support option for the S-VOL, you need to change the option in the primary storage system and then split and resync the pair.
When a pair is split, whether user requested or due to failure, the primary system generates sense information to notify the hosts. If the host system supports PPRC and the PPRC support CU option is enabled, this notification results in an IEA494I and/or IEA491E system console message, which indicates the reason for suspension.