Replacing and Configuring Appliance Components
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Continuous Access Storage Appliance Installation and Maintenance Guide
Creating partitions on the shared storage array
The shared storage array stores configuration information for both appliance nodes. The array
also enables the appliance nodes to monitor communication between its peer node and the
shared storage array. You must create seven partitions on the array in which to store to
configuration information.
This section describes the following topics:
■
■
Partitions overview
You create the following partitions on the shared storage array:
■
E:\
and
F:\
— Store node heartbeat information. Each node has read-write access to
one partition and read-only access to the other. For example, one node can have read–write
access to
E:\
and read–only access to
F:\
; the other node has read–only access to
E:\
and read–write access to
F:\
.
Every few seconds, each node sends a heartbeat to the partition to which it has read–write
access. The heartbeat is a small data packet that includes a time stamp. The node then
checks the heartbeat on the partition to which it has read–only access. If the node does not
detect a heartbeat on the read–only partition within 30 seconds, it reports that its peer node
has failed. The node then assumes ownership of the configuration information on the
I:\
partition (explained below) until its peer node resumes operation.
■
G:\
and
H:\
— Store the journal files for mirroring operations. Peer node 0 uses
G:\
and peer node 1 uses
H:\
.
■
I:\
— Stores the configuration information for the storage network. Both peer nodes can
access this partition, which contains LUN mapping information, host numbers, DPF
configuration information, mirroring operations, and point-in-time image assignments.
The partition has a file sharing algorithm to ensure that each node queries its peer before
writing data to the partition. This prevents data corruption, enabling you to determine if
the partition is in use.
■
J:\
— Stores information about point-in-time image activity.
■
Q:\
— Stores information about asynchronous IP mirroring operations. The partition is
also referred to as the asynchronous IP mirror queue.
