User Interfaces For Global-Active Device Operations - Hitachi G1000 User Manual

Quorum disk
The quorum disk, required for global-active device, is used to determine the
storage system on which server I/O should continue when a storage system
or path failure occurs. The quorum disk is virtualized from an external
storage system that is connected to both the primary and secondary storage
systems.
Virtual storage machine
A virtual storage system is configured in the secondary system with the same
model and serial number as the (actual) primary system. The servers treat
the virtual storage machine and the storage system at the primary site as
one virtual storage machine.
Paths and ports
GAD operations are carried out between hosts and primary and secondary
storage systems connected by Fibre-Channel data paths composed of one of
more Fibre-Channel physical links.
The data path, also referred to as the remote connection, connects ports on
the primary system to ports on the secondary system. The ports are assigned
attributes that allow them to send and receive data. One data path
connection is required, but two or more independent connections are
recommended for hardware redundancy.
Alternate path software
Alternate path software is used to set redundant paths from servers to
volumes and to distribute host workload evenly across the data paths.
Alternate path software is required for the single-server and cross-path GAD
system configurations.
Cluster software
Cluster software is used to configure a system with multiple servers and to
switch operations to another server when a server failure occurs. Cluster
software is required when two servers are in a GAD server-cluster system
configuration.

User interfaces for global-active device operations

Global-active device operations are performed using the GUI software and the
CLI software for the Virtual Storage Platform G1000:
• Hitachi Command Suite
• Command Control Interface
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Hitachi Virtual Storage Platform G1000 Global-Active Device User Guide
Overview of global-active device