Global-active device status and nondisruptive migration pair operations

Ops Center High Availability User Guide

Version
10.8.x
File Size
3.9 MB
Audience
anonymous
Part Number
MK-99ADM003-10

The following table shows the cache modes of nondisruptive migration and GAD pair operations.

Operation target

Virtual LDEV ID

GAD pair operation

P-VOL

S-VOL

Cache modes for external volume groups of the destination storage system

TM (Cache Through)

N

N

SM (Write Sync)

Y

N

Legend

Y: Can be performed

N: Cannot be performed

The following table shows the possibility of GAD pair operation and cache mode change in nondisruptive migration.

Operation target

Cache modes to which GAD P-VOL can be changed

TM (Cache Through)

SM

EM/DM

GAD P-VOL

N

Y

N

Legend

Y: Can be performed

N: Cannot be performed

The following table shows the possibility of Volume Migration pair operations (when a GAD pair operating with nondisruptive migration is in the initial status).

GAD pair status

Virtual LDEV ID

I/O from the server

Volume Migration operation

Read

Write

Migrate volumes

Stop migrating volumes

SMPL

Specifed

Y

Y

Y

Y

None

N

N

N

Y

None (GAD reserve is specified as the virtual attribute)

N

N

N

Y

Legend

Y: Can be performed

N: Cannot be performed

The following table shows the possibility of Volume Migration pair operations (when a GAD pair operating with nondisruptive migration is being mirrored).

GAD pair status

I/O mode

Pair location

I/O from the server

Volume Migration operation

Read

Write

Migrate volumes

Stop migrating volumes

INIT/COPY

Mirror (RL)

P-VOL

Y

Y

N

Y

Block

S-VOL

N

N

N

Y

Legend

Y: Can be performed

N: Cannot be performed

The following table shows the possibility of Volume Migration pair operations (when a GAD pair operating with nondisruptive migration is already mirrored).

GAD pair status

I/O mode

Pair location

I/O from the server

Volume Migration operation

Read

Write

Migrate volumes

Stop migrating volumes

PAIR

Mirror (RL)

P-VOL

Y

Y

Y

Y

Block

S-VOL

N

N

N

Y

Legend

Y: Can be performed

N: Cannot be performed

The following table shows the possibility of Volume Migration pair operations (when a GAD pair operating with nondisruptive migration is suspended).

GAD pair status

I/O mode

Pair location

I/O from the server

Volume Migration operation

Read

Write

Migrate volumes

Stop migrating volumes

PSUS/PSUE

Local

P-VOL

Y

Y

Y

Y

Block

Volume of your own choice (P-VOL or S-VOL)

N

N

Y

Y

SSUS

Block

S-VOL

N

N

Y

Y

SSWS

Local

S-VOL

Y

Y

Y

Y

Legend

Y: Can be performed

N: Cannot be performed

The following table shows the possibility of Volume Migration pair operations (when a GAD pair operating with nondisruptive migration is blocked).

GAD pair status

I/O mode

Pair location

I/O from the server

Volume Migration operation

Read

Write

Migrate volumes

Stop migrating volumes

PSUE

Block

P-VOL

N

N

Y

Y

S-VOL

N

N

Y

Y

Legend

Y: Can be performed

N: Cannot be performed

The following table shows the GAD pair status in Volume Migration when GAD and nondisruptive migration are used together, and the possibility of Volume Migration pair operations (when the GAD P-VOL is a target volume of Volume Migration).

Volume Migration pair status

Is VM P-VOL shared with NDM?

Is VM S-VOL shared with NDM?

GAD pair operation

Create

Suspend

Delete

Resynchronize

P-VOL specified

S-VOL specified

P-VOL specified 1

S-VOL specified 2

Force delete

P-VOL specified 3

S-VOL specified

SMPL (PD)

Yes

No4

Y

Y

Y

Y

N

Y

N

N

COPY

Yes

No4

N

Y

Y

Y

N

Y

N

N

PSUE

Yes

No4

N

Y

Y

Y

N

Y

N

N

PSUS

No4

Yes

N

Y

Y

Y

N

Y

N

N

Legend

VM: Volume Migration

NDM: nondisruptive migration

Y: Can be performed

N: Cannot be performed

Note:
  1. You can delete a GAD pair by specifying its P-VOL, only when the I/O mode is Local and the pair status of the P-VOL is PSUS or PSUE.
  2. You can delete a GAD pair by specifying its S-VOL, only when the I/O mode is Local and the pair status of the S-VOL is SSWS.
  3. If a GAD pair is suspended due to a failure, you can resynchronize it by deleting the Volume Migration pair, and then specifying the GAD P-VOL.
  4. You cannot use the S-VOL of Volume Migration as a volume of nondisruptive migration.