GAD pair and Universal Replicator pair interoperability

Global Active Device for VSP One Block

Version

10.5.x

File Size

25537 KB

Audience

anonymous

Part Number

MK-23VSP1B011-11

ft:lastEdition

2026-06-23

You should know how GAD pairs and Universal Replicator pairs work together for different pair statuses for GAD pairs or UR pairs.

The following table shows GAD pair operations and whether they can be performed (Yes or No) with the listed UR pair status.

Table. GAD operations and UR pair statuses
UR pair status	Attribute of the target UR pair	GAD pair operation
		Create pairs¹	Split pairs	Suspend pairs	Resynchronize pairs		Delete pairs
		Create pairs¹	P-VOL specified	S-VOL specified	P-VOL specified	S-VOL specified	P-VOL or S-VOL specified
COPY	P-VOL	No	Yes	impossible	Yes	Yes	No²
COPY	S-VOL	No	No³	impossible	No	impossible	No²
PAIR	P-VOL	No⁴	Yes	impossible	Yes	Yes	No²
PAIR	S-VOL	No	No³	impossible	No	impossible	No²
PSUS	P-VOL	No⁴	Yes	impossible	Yes	Yes	No²
PSUE	P-VOL	No⁴	Yes	impossible	Yes	Yes	No²
PSUE	S-VOL	No	No³	impossible	No	impossible	No²
SSUS	S-VOL	No	No³	impossible	No	impossible	No²
SSWS	S-VOL	No	No³	impossible	No	impossible	No²
HOLD	P-VOL	No	impossible	Yes	impossible	impossible	No²
HOLD	S-VOL	No	impossible	impossible	impossible	impossible	No²
HLDE	P-VOL	No	impossible	Yes	impossible	impossible	No²
HLDE	S-VOL	No	impossible	impossible	impossible	impossible	No²
Note: When creating a GAD and UR configuration, create a GAD pair first. When deleting a GAD pair, delete the UR pair and the UR delta resync pair first. The UR S-VOL is also used as the GAD P-VOL only when the UR S-VOL is duplicated using GAD. In this case, the GAD P-VOL status must be PSUS, therefore, the pair split terminates abnormally. When migrating UR pairs using GAD, you can create a GAD pair. However, if the GAD pair is created in this combination, a 3DC delta resync configuration cannot be established.

The following table shows UR pair operations and whether they can be performed (Yes or No) with the listed GAD pair status.

Table. UR pair operations and GAD pair statuses
GAD pair status	I/O mode	Attribute of the target GAD pair	UR pair operation
			Create pairs	Split pairs	Suspend pairs	Resynchronize pairs
			Create pairs	P-VOL specified	S-VOL specified	P-VOL specified	S-VOL specified
INIT/COPY	Mirror (RL)	P-VOL	No	Yes	impossible	Yes¹	impossible
INIT/COPY	Block	S-VOL	No	impossible	impossible	impossible	impossible
COPY	Mirror (RL)	P-VOL	No	Yes	impossible	Yes¹	impossible
COPY	Block	S-VOL	No	impossible	impossible	impossible	impossible
PAIR	Mirror (RL)	P-VOL	Yes²	Yes	impossible	Yes¹	impossible
PAIR	Mirror (RL)	S-VOL	No	impossible	impossible	impossible	impossible
PSUS	Local	P-VOL	No	Yes	Yes³	Yes¹	Yes³
PSUS	Block	P-VOL	No	Yes	Yes³	No	impossible
PSUE	Local	P-VOL	No	Yes	Yes³	Yes¹	Yes³
PSUE	Block	P-VOL	No	Yes	Yes³	No	impossible
SSUS	Block	S-VOL	No	impossible	impossible	impossible	impossible
SSWS	Local	S-VOL	No	Yes	impossible	Yes	impossible
Note: Can be performed only when the UR delta resync pair status is HLDE. GAD pairs can be used with UR pairs only when the volume specified as the UR S-VOL is a UR delta resync S-VOL. The UR S-VOL is also used as the GAD P-VOL only when the UR S-VOL is duplicated using GAD.

The following table shows UR delta resync pair operations and whether they can be performed (Yes or No) with the listed GAD pair status.

Table. UR delta resync pair operations and GAD pair statuses
GAD pair status	I/O mode	Attribute of the target GAD pair	UR delta resync pair operation
			Create UR delta resync pair	Delta resync	Delete pairs
			Create UR delta resync pair	Delta resync	P-VOL specified	S-VOL specified	UR delta resync P-VOL	UR delta resync S-VOL
INIT/COPY	Mirror (RL)	P-VOL	No	No¹	Yes	impossible	impossible	impossible
INIT/COPY	Block	S-VOL	No	No¹	impossible	impossible	impossible	impossible
COPY	Mirror (RL)	P-VOL	No	No¹	Yes	impossible	impossible	impossible
COPY	Block	S-VOL	No	No¹	impossible	impossible	impossible	impossible
PAIR	Mirror (RL)	P-VOL	No	No¹	Yes	impossible	impossible	impossible
PAIR	Mirror (RL)	S-VOL	Yes	No¹	impossible	impossible	Yes⁴	impossible
PSUS	Local	P-VOL	No	No¹	Yes	Yes³	Yes⁴	impossible
PSUS	Block	P-VOL	Yes²	No¹	Yes	Yes³	Yes⁴	impossible
PSUE	Local	P-VOL	No	No¹	Yes	Yes³	Yes⁴	impossible
PSUE	Block	P-VOL	Yes²	No¹	Yes	Yes³	Yes⁴	impossible
SSUS	Block	S-VOL	No	No¹	impossible	impossible	Yes⁴	impossible
SSWS	Local	S-VOL	No	No¹	Yes	impossible	Yes⁴	impossible
Note: Cannot be performed by users. The storage system performs the operation automatically. If a failure occurs at the primary site, the operation can be performed only when the volume specified as the UR delta resync S-VOL is the UR S-VOL. The UR S-VOL is also used as the GAD P-VOL only when the UR S-VOL is duplicated using GAD. Deleting a UR delta resync pair deletes the UR pair.