Regression and recovery of ca, Regression and recovery of ca 356, Scenario – HP XP Continuous Access Software User Manual

Page 356: The p-vol detects a failure in the s

356

HP StorageWorks Disk Array XP RAID Manager: User’s Guide

Regression and recovery of CA

The figure below shows a diagram of regression and recovery where
horctakeover

is not needed.

Scenario

1. The P-VOL detects a failure in the S

VOL or the link and suspends

mirroring. (It depends on the fence level whether host A continues
processing or host B takes over processing from host A.)

2. The P-VOL changes its paired volume status to PSUE and keeps track

of data changes in a difference bitmap. The CA manager detects the
status change and outputs a message to syslog. If a host A user has
initiated a monitoring command, a message is displayed on the client’s
screen.

Link

failure

S-VOL

failure

Disconnected

Continue (regression)

Host A

Host B

vol

Host A

Host B

vol

Host A

Host B

vol

Continue (regression)

pairsplit -S

paircreate

e Entire copy

S-VOL goes down.

S-VOL recovers.

Host A

Host B

vol

Host A

Host B

vol

Host A

Host B

vol

pairresync

e Difference

Recovery

Mirroring state

Regression state

Recovery state

This manual is related to the following products:

XP RAID Manager Software