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SHADOW_PSM_RDLY is a system parameter that adjusts the delay on a shadow set copy or merge operation in environments where the shadow set is mounted on more than one system and some members are MSCP-served.

When a copy or merge operation is needed on a shadow set that is mounted on more than one system, the shadowing driver attempts to perform the operation on a system that has a local connection to all the shadow set members. Shadowing implements the copy or merge operation by adding a time delay based on the number of shadow set members that are MSCP-served to the system. No delay is added for local members; a system with all locally accessible shadow set members usually performs the copy or merge before a system on which one or more members is served (and therefore is delayed) does. SHADOW_PSM_RDLY allows the system manager to adjust the delay that shadowing adds. By default, the delay is 30 seconds for each MSCP-served shadow set member. The valid range for the specified delay is 0 through 65,535 seconds. When a shadow set is mounted on a system, the value of SHADOW_ PSM_RDLY is used as the default shadow set member recovery delay for that shadow set. To modify SHADOW_PSM_RDLY for an existing shadow set, see the SET SHADOW/ /RECOVERY_OPTIONS=DELAY_PER_ SERVED_MEMBER=n command in VSI Volume Shadowing for OpenVMS.