Supported Data Path Configurations; Direct Connection - Hitachi G200 User Manual

Supported data path configurations

Three configurations are supported for TrueCopy:
• Direct connection on page 3-29
• Switch connection on page 3-30
• Extender connection on page 3-32
You can use the GUI (Device Manager - Storage Navigator or Hitachi
Command Suite) or the CLI (Command Control Interface) to set ports and
topology.
For direct and switch connections, host I/O response time can be improved
on long-distance direct connections (longwave, less than 10 km/6.2 miles) by
improving the I/O response time between storage systems and by using host
mode options (HMOs) 49 and 50, or HMO 51. The following table describes
these options. A Hitachi Data Systems-approved channel extender is
required. For details about HMOs, see the Provisioning Guide for Hitachi
Virtual Storage Platform Gx00 and Fx00 Models.
HMO
49
50
51
Notes:
1 Up to 10 km for direct connection and 100 km for switch connection.
.
2 The firmware supporting these functions must be installed on both the primary and
.
secondary systems.

Direct connection

The following figure shows a direct connection, in which two devices are
connected directly together.
Hitachi TrueCopy® User Guide for Hitachi Virtual Storage Platform Gx00 and Fx00 Models
Title
BB Credit Set Up Fixes higher values of buffer-to-buffer credits (BBCs) to
Option 1
increase data transfer size over long distances.
host mode option must be used in conjunction with host
mode option 50.
BB Credit Set Up Fixes higher values of buffer-to-buffer credits (BBCs) to
Option 2
increase data transfer size over long distances.
host mode option must be used in conjunction with host
mode option 49.
Round Trip Set Improves host I/O response time for long distance switch
Up Option
connections.
Planning for TrueCopy
Description
2
2
2
1
This
1
This
3-29