IBM System storage DS6000 Series, Redbook

Page: 131 / 578

Chapter 9. FlashCopy interfaces
107
Inband FlashCopy can be useful if the host at the recovery site is not online. The Inband
option eliminates the need for a host connection from local to remote exclusively for
FlashCopy backup. The FlashCopy request must be issued at a host processor connected to
the remote mirror or copy primary volume, with the remote mirror or copy secondary volume
specified as the FlashCopy source.
Example 9-18 Inband FlashCopy
//*********************************************************************
//* ESTABLISH INBAND FLASHCOPY RELATIONSHIP *
//* DEVN - METRO MIRROR PRIMARY VOLUME AT LOCAL SITE *
//* SOURCE - DS6000 SERIAL NO, LSS, CCA AT REMOTE SITE *
//* TARGET - DS6000 SERIAL NO, LSS, CCA AT REMOTE SITE *
//*********************************************************************
//STEP1 EXEC PGM=IKJEFT01,REGION=256K
//SYSTSPRT DD SYSOUT=*
//SYSUADS DD DSN=SYS1.UADS,DISP=SHR
//SYSLBC DD DSN=SYS1.BRODCAST,DISP=SHR
//SYSTSIN DD *
FCESTABL DEVN(X'3500') SOURCE(ABTV1 05 0A) -
TARGET(ABTV1 05 0B) -
MODE(COPY) SSID(4500) REMOTE(YES)
/*
In the Example 9-18, the REMOTE(YES) parameter specifies that this relationship is to be
located on the remote DS6000 storage subsystem identified by SSID 4500. This must be the
same as the SSID value specified for the Metro Mirror secondary on the TSO CESTPAIR
command. DEVN 3500 is the Metro Mirror primary through which the FCESTABL command
will be passed.
FlashCopy in a Global Mirror session
Example 9-19 shows the TSO FCESTABL command with MODE(ASYNC), which is used
when FlashCopy is part of a Global Mirror configuration. Since the ASYNC mode establishes
an incremental relationship, the INCREMENTAL(YES) parameter is not needed. In addition,
the FlashCopy target is write-inhibited.
Example 9-19 TSO FCESTABL and MODE(ASYNC)
//*********************************************************************
//* ESTABLISH FLASHCOPY RELATIONSHIP FOR GLOBAL MIRROR SESSION *
//* SDEVN - SOURCE FLASHCOPY VOLUME *
//* TDEVN - TARGET FLASHCOPY VOLUME *
//*********************************************************************
//STEP1 EXEC PGM=IKJEFT01,REGION=256K
//SYSTSPRT DD SYSOUT=*
//SYSUADS DD DSN=SYS1.UADS,DISP=SHR
//SYSLBC DD DSN=SYS1.BRODCAST,DISP=SHR
//SYSTSIN DD *
FCESTABL SDEVN(X'3500') TDEVN(X'4500') MODE(ASYNC)
FCESTABL SDEVN(X'3501') TDEVN(X'4501') MODE(ASYNC)
/*
Fast Reverse Restore is another function to be used with a Global Mirror configuration. It is
used when recovering from an outage. This function reverses the direction of the FlashCopy
relationship when change recording is active (incremental FlashCopy), restoring the source
volume to the state it was in when it last flashed to the target. Changed tracks are copied
back from the target to the source.