Hitachi G200 - Page 4

Workflow for removing control memory.................................................... 3-3
System option modes........................................................................................3-4
System performance considerations......................................................................... 3-5
Determining Round Trip Time............................................................................3-5
Determining Minimum Number of Remote Paths................................................. 3-7
Analyzing workload, planning data paths............................................................3-8
Planning pairs and pair volumes...............................................................................3-8
Pair volume requirements and recommendations................................................ 3-9
Allowing I/O to the S-VOL............................................................................... 3-10
Allowing I/O to the P-VOL after a split—Fence Level options.............................. 3-10
Differential data .............................................................................................3-11
Maximum number of pairs supported............................................................... 3-12
Calculating maximum number of pairs.................................................... 3-13
Priority for initial copy operations and scheduling order..................................... 3-15
Example 1: more initial copies than previously specified........................... 3-15
Example 2: initial copy started, new pairs added......................................3-15
Consistency group planning................................................................................... 3-16
Consistency group for pairs in one primary and one secondary system............... 3-16
Consistency group for pairs in multiple primary and secondary systems.............. 3-17
System configurations for consistency groups..........................................3-19
Registering pairs to a new consistency group.......................................... 3-19
Registering pairs to an existing consistency group................................... 3-20
Consistency group requirements ..................................................................... 3-20
Split behaviors................................................................................................3-21
Operation when a split command is issued during I/O processing (for
TrueCopy).............................................................................................3-22
Operation when an I/O request is received while a split command is in
progress............................................................................................... 3-22
Host access after split............................................................................3-22
Pair status before and after a split operation........................................... 3-23
Consistency group 127....................................................................................3-23
CTG 127 behavior and restrictions when a pair is suspended.................... 3-24
CTG 127 behavior and restrictions when the data path fails......................3-24
Host failover software........................................................................................... 3-25
Data path requirements and configurations.............................................................3-25
Ports..............................................................................................................3-26
Bandwidth requirements..................................................................................3-26
Fibre Channel data path requirements..............................................................3-26
iSCSI data path requirements.......................................................................... 3-27
Supported data path configurations..................................................................3-29
Direct connection.................................................................................. 3-29
Switch connection................................................................................. 3-30
Extender connection.............................................................................. 3-32
4 Sharing TrueCopy volumes....................................................................4-1
Volume types that can be shared with TrueCopy.......................................................4-2
Data Retention Utility.............................................................................................. 4-4
Dynamic Provisioning ............................................................................................. 4-5
LUN Manager ........................................................................................................ 4-6
Performance Monitor...............................................................................................4-6
Universal Replicator ............................................................................................... 4-7
ShadowImage........................................................................................................ 4-7
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Hitachi TrueCopy® User Guide for Hitachi Virtual Storage Platform Gx00 and Fx00 Models