Storage Systems; Volume Pairs - Hitachi G200 User Manual

Storage systems

TrueCopy operations require Hitachi storage systems at both the primary and
the secondary sites.
The primary system manages the P-VOL and the following operations:
• Host I/O operations to the P-VOL.
• Initial copy and update copy operations between the P-VOL and S-VOL.
• Pair status and configuration information.
The secondary system manages the S-VOL and the following operations:
• Secondary copy operations issued by the primary system.
• Assists in managing pair status and configuration (for example, rejects
write I/Os to the S-VOL).
The primary system communicates with the secondary system over dedicated
Fibre Channel or iSCSI data paths.

Volume pairs

As described previously, original data is stored in the P-VOL and the remote
copy is stored in the S-VOL. The pair can be split, resynchronized, reverse
resynchronized, and returned to unpaired status.
• When paired, the volumes are synchronized.
• When split, new data is sent to the P-VOL but not the S-VOL.
Note: It will continue writing to P-VOL but copying to S-VOL stops so that
pair will not be synchronized.
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Hitachi TrueCopy® User Guide for Hitachi Virtual Storage Platform Gx00 and Fx00 Models
TrueCopy overview