Figure 68 Mapping Tfovs, Tfo Groups, And Ca Port Pairs; Table 38 Storage Cluster Function Specifications - Fujitsu ETERNUS AF250 Design Manual

1. Function
Stable Operation via Load Control
TFOVs are mirrored and maintained equally as a pair in the Primary storage and the Secondary storage. Because
the remote copy technology is using synchronization, to mirror between storage systems, besides configuring
the Storage Cluster-related settings, the copy path must also be set.

Figure 68 Mapping TFOVs, TFO Groups, and CA Port Pairs

CA#0
TFOV#0
TFOV#1
Primary storage
• TFOV
Transparent Failover Volume (TFOV) is a volume in which the Storage Cluster setting is performed. Server ac-
cess 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 DX/AF, and a Stor-
age 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" indi-
cates that access from a business server is disabled.
CA port pair
•
By sharing the WWPN/WWNN for the FC or by sharing the IP address and iSCSI name for the iSCSI with the CA
ports of two ETERNUS DX/AF storage systems, the Storage Cluster function performs a failover by controlling
the Link status of each CA port.
This pair of CA ports that share the WWPN and WWNN, or the IP address and iSCSI name is called a CA port
pair.
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.
The following table provides the function specifications for the Storage Cluster.

Table 38 Storage Cluster Function Specifications

Item
Number of connectable storage systems
Business server connections
CA port pair
CA#1
TFOV#2
TFO group
FUJITSU Storage ETERNUS AF250 S2, ETERNUS AF250 All-Flash Arrays Design Guide (Basic)
Copyright 2019 FUJITSU LIMITED
CA port pair
CA#0
TFOV#0
TFOV#1
Create
an association
Secondary storage
Specifications
1
Switch connections only
106
CA#1
TFOV#2
TFO group
P3AG-1822-09ENZ0