Hitachi G200 - Page 26

Item Requirement
• Maximum number of path groups: 64 per storage system
• Path group ID:
¢
0-255 (0 to FF in hexadecimal) when connected to VSP
Gx00 models, VSP Fx00 models, or VSP.
¢
0 when connected to USP V/VM or HUS VM.
• Protocol: All remote paths in a path group must be the same
protocol, either Fibre Channel or iSCSI. Remote paths for Fibre
Channel and iSCSI cannot coexist within the same path group.
• If iSCSI is used in a remote path, the Blocked Path Monitoring
remote replica option must be set to at least 40 seconds
(default). If Blocked Path Monitoring is less than 40 seconds,
the path might be blocked due to a delay in the network such
as many switches in a spanning tree protocol (STP) network or
a long distance connection.
• The path group is specified during the create pair operation. It
cannot be changed by the resync pair operation.
• Path groups can be created and specified using CCI. See
configuration setting commands in Command Control Interface
User and Reference Guide and sample configuration definition
files in Command Control Interface Installation and
Configuration Guide.
• It is recommended that you specify different paths and path
groups for UR secondary systems when using CU Free.
Maximum number
of secondary
systems (System)
Up to 64 secondary TC or UR systems can be set per primary
system.
Pair volumes • The P-VOL and S-VOL must be equal in size.
• The maximum size of the P-VOL and S-VOL are:
¢
Dynamic Provisioning virtual volume (DP-VOL), the same
as the maximum size of the DP-VOL.
See the Provisioning Guide for Hitachi Virtual Storage
Platform Gx00 and Fx00 Models.
¢
Internal volume: 3,145,663 MB (6,442,317,824 blocks).
¢
External volume: 4,194,304 MB (8,589,934,592 blocks).
• The minimum size for P-VOLs and S-VOLs is 46.875MB
(96,000 blocks).
• A P-VOL can be copied to only one S-VOL.
• The P-VOL and S-VOL can be shared with other Hitachi
software product volumes. See
Volume types that can be
shared with TrueCopy on page 4-2.
• The same value must be set for the T10 PI attribute of the P-
VOL and S-VOL.
• You cannot use a volume in a parity group for which
accelerated compression is enabled as a pair volume.
• You cannot use the system LU for Hitachi NAS Platform as a
pair volume.
See
Planning pairs and pair volumes on page 3-8 for more
information.
2-4
Requirements and specifications
Hitachi TrueCopy® User Guide for Hitachi Virtual Storage Platform Gx00 and Fx00 Models