Figure 74
Mapping TFOVs, TFO Groups, and CA Port Pairs
CA#1
Secondary storage
CA#0
Primary storage
TFOV#0
TFOV#1
TFO group
TFO group
TFOV#2
CA#1
CA#0
TFOV#0
TFOV#1
TFOV#2
CA port pair
CA port pair
Create
an association
•
TFOV
Transparent Failover Volume (TFOV) is a volume in which the Storage Cluster setting is performed. Server
access is possible even when a failover occurs.
•
TFO group
A Transparent Failover (TFO) group is the operations unit for a failover in a single ETERNUS AF/DX, and a
Storage Cluster failover is performed for each group.
A TFO group has two states. "Active" indicates that access from a business server is enabled and "Standby"
indicates that access from a business server is disabled.
•
CA port pair
The Storage Cluster function performs a failover by setting the same port identifier for the CA ports of two
ETERNUS AF/DX storage systems and by controlling the Link status of each CA port. The port identifier is
WWPN/WWNN for FC ports or an IP address and iSCSI name for iSCSI ports.
This pair of CA ports with the same WWPN/WWNN or the same IP address and iSCSI name is called a CA port
pair.
Note
If a different IP address is used for the CA port pair with iSCSI, a failover and failback must be performed
manually so that the Primary storage and the Secondary storage recognize the path.
3. SAN Functions
Stable Operation
143
Design Guide
Summary of Contents for ETERNUS DX S5 Series
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