Description

This article outlines the steps required to split the Hitachi ShadowImage (SI) svol (S-VOL) disks using the Hitachi Command Control Interface (CCI) making them read-write (RW).

Once split and in a read-write (RW) state, the Veritas Volume Manager (VxVM) related disk group can then be imported.

HORCM stands for Hitachi Online Remote Copy Manager.
 

The CCI software is required to open a communication channel from the server to the locally attached Hitachi array.
Ensure the CCI software has been downloaded and configured before performing the following steps.

# pwd
/HORCM

The "RMinstsh" script can be used to install the Command Control Interface (CCI) software on the host.

NOTE: The steps outlined in the article have been performed on a Linux (RedHat) server for illustration purposes.

Steps:

1.] Identify the Hitachi svol ShadowImage (SI) disks

When using Veritas DMP, the "vxdisk -e list" command will report svol for Secondary (target) Hitachi ShadowImage (SI) disks.

In this instance, the VxVM disk group is named "Shadow".
 

View of Hitachi ShadowImage (SI) pvol (P-VOL) from the source server:

PROD # vxdisk -eo alldgs list | grep Shadow
hitachi_vspgx0_05da auto:cdsdisk   hitachi_vspgx0_05da  Shadow      online thinrclm      sdj              hdprclm fc pvol
hitachi_vspgx0_05db auto:cdsdisk   hitachi_vspgx0_05db  Shadow      online thinrclm      sdk              hdprclm fc pvol
h

itachi_vspgx0_05dc auto:cdsdisk   hitachi_vspgx0_05dc  Shadow      online thinrclm      sdl              hdprclm fc pvol
hitachi_vspgx0_05dd auto:cdsdisk   hitachi_vspgx0_05dd  Shadow      online thinrclm      sdm              hdprclm fc pvol
hitachi_vspgx0_05de auto:cdsdisk   hitachi_vspgx0_05de  Shadow      online thinrclm      sdn              hdprclm fc pvol
hitachi_vspgx0_05df auto:cdsdisk   hitachi_vspgx0_05df  Shadow      online thinrclm      sdo              hdprclm fc pvol
hitachi_vspgx0_05d9 auto:cdsdisk   hitachi_vspgx0_05d9  Shadow      online thinrclm      sdi              hdprclm fc pvol
 

View of Hitachi ShadowImage (SI) svol (S-VOL) from the target server:

DR # vxdisk -eo alldgs list | grep Shadow
hitachi_vspgx0_05e0 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdx              hdprclm fc svol
hitachi_vspgx0_05e1 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdy              hdprclm fc svol
hitachi_vspgx0_05e2 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdz              hdprclm fc svol
hitachi_vspgx0_05e3 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdaa             hdprclm fc svol
hitachi_vspgx0_05e4 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdab             hdprclm fc svol
hitachi_vspgx0_05e6 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdad             hdprclm fc svol
 

2.]  Export the following HORCM based variables

# export HORCMINST=1

for Hitachi ShadowImage (SI) environments:

# export HORCC_MRCF=1
 

3.] To show the state of the Hitachi devices, type:
 

The volume group is "vg1" in this instance.
 

View of Hitachi ShadowImage (SI) pvol from the source (production) server:
 

PROD # pairdisplay -g vg1 -I1 -fxd -l
Group   PairVol(L/R) Device_File    M  ,Seq#,LDEV#.P/S,Status, Seq#,P-LDEV# M
vg1     vg1_000(L)   sdj            0  413010   5da.P-VOL PAIR,413010     5e1 -
vg1     vg1_001(L)   sdk            0  413010   5db.P-VOL PAIR,413010     5e2 -
vg1     vg1_002(L)   sdl            0  413010   5dc.P-VOL PAIR,413010     5e3 -
vg1     vg1_003(L)   sdm            0  413010   5dd.P-VOL PAIR,413010     5e4 -
vg1     vg1_004(L)   sdn            0  413010   5de.P-VOL PAIR,413010     5e5 -
vg1     vg1_005(L)   sdo            0  413010   5df.P-VOL PAIR,413010     5e6 -
vg1     vg1_006(L)   sdi            0  413010   5d9.P-VOL PAIR,413010     5e0 -

The additional -ISI options can be specified to denote ShadowImage (SI) devices, followed by the HORCM instance number:

PROD # pairdisplay -g vg1 -ISI1 -fxd -l
Group   PairVol(L/R) Device_File    M  ,Seq#,LDEV#.P/S,Status, Seq#,P-LDEV# M
vg1     vg1_000(L)   sdj            0  413010   5da.P-VOL PAIR,413010     5e1 -
vg1     vg1_001(L)   sdk            0  413010   5db.P-VOL PAIR,413010     5e2 -
vg1     vg1_002(L)   sdl            0  413010   5dc.P-VOL PAIR,413010     5e3 -
vg1     vg1_003(L)   sdm            0  413010   5dd.P-VOL PAIR,413010     5e4 -
vg1     vg1_004(L)   sdn            0  413010   5de.P-VOL PAIR,413010     5e5 -
vg1     vg1_005(L)   sdo            0  413010   5df.P-VOL PAIR,413010     5e6 -
vg1     vg1_006(L)   sdi            0  413010   5d9.P-VOL PAIR,413010     5e0 -

4.] The raidvchkdsp command displays the parameters for validation checking of the specified volumes.

The following "raidvchkdsp" outputs can be useful for display similar results to the pairdisplay output above
 

PROD # raidvchkdsp -v aou -g vg1 -ISI1
Group   PairVol   Port#  TID  LU  Seq# LDEV#  Used(MB) LU_CAP(MB) U(%) T(%) PID
vg1     vg1_000  CL1-E    0  191 413010  1498      588       1024   14  100    1
vg1     vg1_001  CL1-E    0  192 413010  1499       84       1024   14  100    1
vg1     vg1_002  CL1-E    0  194 413010  1500       84       1024   14  100    1
vg1     vg1_003  CL1-E    0  195 413010  1501     1050       1024   14  100    1
vg1     vg1_004  CL1-E    0  196 413010  1502       84       1024   14  100    1
vg1     vg1_005  CL1-E    0  197 413010  1503      168       1024   14  100    1
vg1     vg1_006  CL1-E    0  190 413010  1497      210       1024   14  100    1
 

PROD # raidvchkdsp -v aou -g vg1 -ISI1 -fxd
Group   PairVol  Device_File      Seq# LDEV#  Used(MB) LU_CAP(MB) U(%) T(%) PID
vg1     vg1_000  sdj             413010   5da      588       1024   14  100    1
vg1     vg1_001  sdk             413010   5db       84       1024   14  100    1
vg1     vg1_002  sdl             413010   5dc       84       1024   14  100    1
vg1     vg1_003  sdm             413010   5dd     1050       1024   14  100    1
vg1     vg1_004  sdn             413010   5de       84       1024   14  100    1
vg1     vg1_005  sdo             413010   5df      168       1024   14  100    1
vg1     vg1_006  sdi             413010   5d9      210       1024   14  100    1

5.] The remote S-VOL SI devices can be split (made read-write), so the remote VxVM disk group image can be imported on the DR host.

PROD # pairsplit -g vg1 -ISI1  -l

6.]  The remote S-VOL SI devices are now shown with the "W" flag

PROD # pairdisplay -g vg1 -ISI1 -fxd -l
Group   PairVol(L/R) Device_File    M  ,Seq#,LDEV#.P/S,Status, Seq#,P-LDEV# M
vg1     vg1_000(L)   sdj            0  413010   5da.P-VOL PSUS,413010     5e1 W
vg1     vg1_001(L)   sdk            0  413010   5db.P-VOL PSUS,413010     5e2 W
vg1     vg1_002(L)   sdl            0  413010   5dc.P-VOL PSUS,413010     5e3 W
vg1     vg1_003(L)   sdm            0  413010   5dd.P-VOL PSUS,413010     5e4 W
vg1     vg1_004(L)   sdn            0  413010   5de.P-VOL PSUS,413010     5e5 W
vg1     vg1_005(L)   sdo            0  413010   5df.P-VOL PSUS,413010     5e6 W
vg1     vg1_006(L)   sdi            0  413010   5d9.P-VOL PSUS,413010     5e0 W


NOTE: The S-VOL SI devices in this instance are LDEVs 5e0 through to 5e6.

PSUS & SSUS

The SI pair(s) have been split by the user and the P-VOL & S-VOL are no longer synchronized.

• The storage system keeps track of journal data discarded during the split operation.
• When the pairsplit operation is performed on the storage system, the status of the P-VOL devices will reflect PSUS, whilst the S-VOL will be shown as SSUS.

DR SERVER
 

7.]  Once split, the pairdisplay output for the S-VOL devices will shown the "SSUS" state. 

DR # pairdisplay -g vg1 -ISI1 -fxd -l
Group   PairVol(L/R) Device_File    M  ,Seq#,LDEV#.P/S,Status, Seq#,P-LDEV# M
vg1     vg1_000(L)   sdaa           0  413010   5e3.S-VOL SSUS,-----     5dc -
vg1     vg1_001(L)   sdab           0  413010   5e4.S-VOL SSUS,-----     5dd -
vg1     vg1_002(L)   sdac           0  413010   5e5.S-VOL SSUS,-----     5de -
vg1     vg1_003(L)   sdad           0  413010   5e6.S-VOL SSUS,-----     5df -
vg1     vg1_023(L)   sdx            0  413010   5e0.S-VOL SSUS,-----     5d9 -
vg1     vg1_024(L)   sdy            0  413010   5e1.S-VOL SSUS,-----     5da -
vg1     vg1_025(L)   sdz            0  413010   5e2.S-VOL SSUS,-----     5db -

8.] Refresh the DMP extended attributes prior to importing the VxVM (SI) disk group image using the S-VOL devices.

DR # vxdisk scandisks

DR # vxdisk -eo alldgs list | grep -w Shadow
hitachi_vspgx0_05e0 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdx              hdprclm fc
hitachi_vspgx0_05e1 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdy              hdprclm fc
hitachi_vspgx0_05e2 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdz              hdprclm fc
hitachi_vspgx0_05e3 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdaa             hdprclm fc
hitachi_vspgx0_05e4 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdab             hdprclm fc
hitachi_vspgx0_05e5 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdac             hdprclm fc
hitachi_vspgx0_05e6 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdad             hdprclm fc
 

9.] As the S-VOL device is a hardware clone of a source device, the "-c" option should NOT be used to import the VxVM disk group image. This is different to the "-C" option used to clear hostid information.
 

DR # vxdg import Shadow
VxVM vxdg ERROR V-5-1-19179 Disk group Shadow: import failed:
Disk is in use by another host

Please refer to system log for details.


10.] As the source disk group image is still imported on the source (production) host, the hostid needs to be cleared with the "-C" option.
 

DR # vxdg -C import Shadow

NOTE: Following the successful import operation, the "clone_disk" flag will set to reflect its hardware clone status.

DR # vxdisk -eo alldgs list | grep -w Shadow
hitachi_vspgx0_05e0 auto:cdsdisk   hitachi_vspgx0_05d9  Shadow      online thinrclm clone_disk  sdx              hdprclm fc
hitachi_vspgx0_05e1 auto:cdsdisk   hitachi_vspgx0_05da  Shadow      online thinrclm clone_disk sdy              hdprclm fc
hitachi_vspgx0_05e2 auto:cdsdisk   hitachi_vspgx0_05db  Shadow      online thinrclm clone_disk sdz              hdprclm fc
hitachi_vspgx0_05e3 auto:cdsdisk   hitachi_vspgx0_05dc  Shadow      online thinrclm  clone_disk sdaa             hdprclm fc
hitachi_vspgx0_05e4 auto:cdsdisk   hitachi_vspgx0_05dd  Shadow      online thinrclm  clone_disk sdab             hdprclm fc
hitachi_vspgx0_05e5 auto:cdsdisk   hitachi_vspgx0_05de  Shadow      online thinrclm  clone_disk sdac             hdprclm fc
hitachi_vspgx0_05e6 auto:cdsdisk   hitachi_vspgx0_05df  Shadow      online thinrclm  clone_disk sdad             hdprclm fc

11.] Deport the VxVM disk group on the remote DR site, prior to resyncing SI volumes.

DR # vxdg deport Shadow

Source / Production Server

12.] Resync the SI volume pairs, using the following pairresync command on the source (production) host
 

PROD #  pairresync  -g vg1 -ISI1 -l
 

13.]  The SI pairs is shown as "PAIR" which means "synchronized".

Updates to the P-VOL are duplicated on the S-VOL disks.

PROD #  pairdisplay -g vg1 -ISI1 -fxd -l
Group   PairVol(L/R) Device_File    M  ,Seq#,LDEV#.P/S,Status, Seq#,P-LDEV# M
vg1     vg1_000(L)   sdj            0  413010   5da.P-VOL PAIR,413010     5e1 -
vg1     vg1_001(L)   sdk            0  413010   5db.P-VOL PAIR,413010     5e2 -
vg1     vg1_002(L)   sdl            0  413010   5dc.P-VOL PAIR,413010     5e3 -
vg1     vg1_003(L)   sdm            0  413010   5dd.P-VOL PAIR,413010     5e4 -
vg1     vg1_004(L)   sdn            0  413010   5de.P-VOL PAIR,413010     5e5 -
vg1     vg1_005(L)   sdo            0  413010   5df.P-VOL PAIR,413010     5e6 -
vg1     vg1_006(L)   sdi            0  413010   5d9.P-VOL PAIR,413010     5e0 -
 

DR Server
 

DR: vxdisk scandisks

DR # vxdisk -eo alldgs list | grep -w Shadow
hitachi_vspgx0_05e0 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdx              hdprclm fc
hitachi_vspgx0_05e1 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdy              hdprclm fc
hitachi_vspgx0_05e2 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdz              hdprclm fc
hitachi_vspgx0_05e3 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdaa             hdprclm fc
hitachi_vspgx0_05e4 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdab             hdprclm fc
hitachi_vspgx0_05e5 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdac             hdprclm fc
hitachi_vspgx0_05e6 auto:cdsdisk   -            (Shadow)    online thinrclm udid_mismatch sdad             hdprclm fc