L1, L2 pair status and supported pair tasks

ShadowImage User Guide

Version

9.8.7

Audience

anonymous

Part Number

MK-98RD9021-17

The pair tasks you can complete on cascaded pairs depend on the L1 and L2 pair status. The tasks are dependent on the following:

The following table lists the L1 pair tasks that you can complete based on the related L2 status.

The following table lists the L2 pair tasks that you can perform based on the related L1 status.

L1 pair status	L2 pair task
L1 pair status	Create pairs	Split pairs	Resync pairs (Normal Copy)¹	Resync pairs (Reverse Copy)¹	Suspend pairs	Delete pairs
COPY(PD)/COPY	YES	NO	YES	NO	YES	YES
PAIR	YES	NO	YES	NO	YES	YES
COPY(SP)/COPY	YES	NO	YES	NO	YES	YES
PSUS(SP)/PSUS	NO	NO	YES	NO	YES	YES
PSUS	YES	YES²	YES	NO	YES	YES
COPY(RS)/COPY	YES	NO	YES	NO	YES	YES
COPY(RS-R)/RCPY	YES	NO	YES	NO	YES	YES
PSUE	YES	NO	YES	NO	YES	YES
For L2 pairs, only Normal Copy or Quick Resync can be performed. You cannot perform a reverse resynchronization (Reverse Copy or Quick Restore). For more information about resynchronizing L2 pairs, see Resynchronizing or restoring ShadowImage pairs. To split L2 pairs, the L1 pair status must be PSUS. For more information about the prerequisites for splitting L2 pairs, see Splitting ShadowImage pairs.

The following table lists the node volume read/write L1 and L2 pair status.

The following table lists the leaf vol read/write per L2 pair status.

L2 pair status
COPY(PD)/COPY	PAIR	COPY(SP)/COPY	PSUS(SP)/PSUS	PSUS	COPY(RS)/COPY	PSUE
Read only	Read only	Read only	Read/Write	Read/Write	Read only	Read only