Ports; Bandwidth Requirements; Fibre Channel Data Path Requirements - Hitachi G200 User Manual

different protocols are used in the data paths (for example, Fibre Channel
data paths between the host and storage system and iSCSI data paths
between the storage systems), the timeout period for commands between
the host and the storage system must be equal to or greater than the
timeout period for commands between the storage systems. This
requirement applies only to TrueCopy data paths (does not apply to
Universal Replicator or global-active device).

Ports

Data is transferred along the connection path from the primary storage
system to the secondary system site.
The amount of data each of these ports can transmit and receive is limited.
Therefore, you must know the amount of data that will be transferred (write-
workload) during peak periods. You can then ensure not only that bandwidth
meets data transfer requirements, but that a sufficient number of each
system's ports are specified to handle all workload levels.

Bandwidth requirements

Sufficient bandwidth must be present to handle data transfer of all workload
levels. The amount of bandwidth required for your TrueCopy system is based
on the amount of I/O sent from the host to the primary system. You
determine required bandwidth by measuring write-workload. Workload data is
collected using performance monitoring software. Consult Hitachi Data
Systems customer support for more information.

Fibre Channel data path requirements

For Fibre Channel data paths, direct, switch, and extender connections are
supported. The primary and secondary systems must be connected using
multimode or single-mode optical fibre cables. As shown in the following
table, the distance between the P-VOL and S-VOL storage systems
determines the required cable type and data path relay equipment.
0 km to 1.5 km (4,920
feet)
1.5 km to 10 km (6.2
miles)
10 km to 30 km (18.6
miles)
Greater than 30 km (18.6
1
miles)
1 TrueCopy operations typically do not exceed 30 km.
.
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Hitachi TrueCopy® User Guide for Hitachi Virtual Storage Platform Gx00 and Fx00 Models
Distance
Multimode shortwave Fibre
Channel interface cables.
Single-mode longwave optical
fibre cables.
Single-mode longwave Fibre
Channel interface cables.
Communications lines are
required.
Planning for TrueCopy
Fibre cable type
Data path relay
equipment
Switch is required for 0.5
km to 1.5 km.
Not required.
Switch is required.
Approved third-party
channel extender
products.