Read requests are read by the P-VOL and then sent to the host. There is no
communication between the primary and secondary systems.
Related topics
•
Monitoring GAD status on page 1-10
•
Global-active device and server I/O on page 1-14
Server I/O when the GAD status is Blocked
When the GAD status is Blocked, the I/O mode of the P-VOL and S-VOL is
Block. Neither volume accepts read/write processing.
Related topics
•
Monitoring GAD status on page 1-10
•
Global-active device and server I/O on page 1-14
Quorum disk and server I/O
The quorum disk is a volume virtualized from an external storage system.
The quorum disk is used to determine the storage system on which server
I/O should continue when a path or storage system failure occurs. The
primary and secondary systems check the quorum disk every 500 ms for the
physical path statuses.
When the primary and secondary systems cannot communicate, the storage
systems take the following actions:
Overview of global-active device
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Summary of Contents for G1000
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