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Pvol-psue takeover, Pvol-psue takeover 335 – HP XP Continuous Access Software User Manual

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HA Failover and failback

335

PVOL-PSUE takeover

The horctakeover command executes a PVOL-PSUE-takeover when the
primary volume cannot report status or refuses writes (for example, data
fence).

• PSUE (or PDUB) and the horctakeover command returns a

PVOL-PSUE-takeover value at exit().

• A PVOL-PSUE-takeover forces the primary volume to the suspend

state (PSUE or PDUB

PSUE*, PAIR

PSUS), which permits

WRITEs to all primary volumes of the group.

The following illustrates how volumes in the same volume group may be of
different status. Only the volumes that were active at the time of link failure
would immediately be PSUE.

Host C

Host A

Host B

PSUS

PSUE*

PSUS

PSUE*

PSUS

PAIR
PAIR
PAIR
PAIR
PAIR

horctakeover

P-VOL

ESCON failure

Host C

Host A

Host B

PAIR

PSUE

PAIR

PSUE

PAIR

PAIR
PAIR
PAIR
PAIR
PAIR

S-VOL

P-VOL

S-VOL

ESCON/FC failure

ESCON/FC failure

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