Time Finder Mirror

Time Finder/Mirrors(BCV) Up to! 995, to perform backup operations on standard volumes, the application and file system should be shutdown .So the downtime is mandatory. In order to overcome the downtime and to achieve RTO=0,Split mirror technology was introduced.Which lead to the generation of BCV s BUSINESS CONTINUANCE VOLUMES. BUSINESS CONTINUANCE VOLUMES: •

IT facilitates unplanned downtime

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It provides dynamic, full image copies of data

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Data protection and stand-by data for fast recovery

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Decision support

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Back-up

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Parallel information/Data Access

BCV device is used to create an additional mirror image of a standard device in order to provide the facilities mentioned above. Business continuance is achieved through BCV devices, the standard stand-alone Symmetrix devices that are specially configured to be dynamic mirrors. BCV devices should be synchronized with standard devices to perform replication and obtain point –in time physical mirror copies. (Make sure that the size of the BCV device should be equal to the size of the Standard device to which it pairs with) How to create BCV devices?

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Create standard devices and should be configured as unprotected.

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Map the device

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Convert the device

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Commit

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Discover the device

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Update the VCM database

*The above procedure is run at the time of creation of devices

Types of BCV Mirroring 1. Mirroring 2. Multi BCV 3. Concurrent BCV 4. Remote Mirroring(SRDF) * Type 1,2,&3 are performed in the local sym,where as type 4 is performed across the syms. Operations performed on BCVs

1. Establish: Synchronize the standard volume with the BCV volumes. There are two types of synchronizations full and incremental. The first synchronization is always full and the rest are mostly incremental.

2. Split: Terminate relationship between BCV and Standard Devices. There are two types of splits instant split and consistent split. From Engenuity 5x68 instant split has become a default split.

3. Restore

During the restore operation, data on the standard is replaced with the data

brought from the BCV device. During this phase Applications must be stopped file system to be unmounted and should have volume groups deactivated.

LAB SESSION USING SOLUTION ENABLER SYMCLI PROCEDURE Create a device group to manipulate mirror operations between standard device and BCV in the symm.Add the device pair to the group, i.e, and Standard Device and BCV Device pair. Perform mirror operations. and view the data by using volume managers disk group. Delete the content in the Standard device and restore the data from BCV. FOR REFERENCE: The devices ,hosts and groups are addressed as below Symm -277

Standard Device- 0009

Source host –SUN7

BCV Device- 0023

Target host-SUN5 Device group –mirdg

Disc group -sundg

Source

Sun7 0009 STD

Target

Sun5

0023 BCV

1)CREATE A DEVICE GROUP ADD STANDARD AND BCV DEVICES

a) create a device group of type regular: Sun7# Symdg create mirdg –type regular b) Add standard device to the device group: Sun7#symld –g mirdg add dev 0001 c) Add BCV to the group Sun7#symbcv –g mirdg associate dev 0023

2)NOW FIND YOUR STANDARD DEVICE IN SOURCE SUN7 IF NOT AVAILBLE MASK IT TO FIND IN SOURCE HOST a) Now find the list of devices mapped to the host Sun7# syminq b) Now map the standard device to source host Sun7# symmask -sid 277 –wwn 100000000 add dev 0009 –dir 1c –p 0 –nop Sun7# symmask -sid 277 –wwn 100000000 add dev 0009 –dir 2c –p 0 -nop Sun7# symmask -sid 277 –wwn 100000000 add dev 0009 –dir 15c –p 0 -nop Sun7# symmask -sid 277 –wwn 100000000 add dev 0009 –dir 16c –p 0 –nop c) Now refresh the VCM database Sun7#symmask refresh d) Now scan the devices Sun7# symcfg discover Sun7# cfgadm –al Sun7# cfgadm –c configure c3 (Configure the controller) Sun7#symcfg discover Sun7# symmaskdb list database (device should be seen in the database under sun7) 3)NOW SETUP VOLUME UNDER THE CONTROL OF VOLUME MANAGER a) Check the status of volume manager: sun7#vxdctl mode sun7#vxdctl disable sun7#vxdctl enable b) Scan the discs sun7# devfsadm –Cv sun7#format(Identify the device and label it.To identify check the device path by executing syminq command ) >18 >label >quit c) Initialize the disk sun7#vxdisksetup –i EMC01_9 d) List the device sun7#vxdisk list

e)create disk group sun7#vxdg init sundg disk1=EMC01_9 f)Import the disk grouip sun7#vxdg –fC import sundg g) Create a volume sun7#vxassist –g sundg make vol01 200m h) Start the volume sun7# vxvol –g sundg startall I) To check the disk groups in the volume manger Sun7#vxdisk alldgs list j) Create a file system on the disk group sun7#newfs /dev/vx/rdsk/sundg/vol01 K) Create a mount point Sun7# mkdir BCV L) Mount the volume Sun7#mount /dev/vx/dsk/sundg/vol01 /BCV M) Enter the directory Sun7#cd BCV N) Enter the content in the folder Sun7#cp /etc/r* . O) Display the contents Sun7# ls 4)Now synchronize the volumes a) Establish the relation between standard device and BCV sun7# symmir –g mirdg est –full b) Now check the status of device group sun7# symmir –g mirdg query sun7#symmir list 5) Split the relation (In order to split the volume unmount the source; If it is a consistent split, need not to unmount the volume) a)Sun7#symmir –g mirdg split –consistent Check the status

b) Sun7#symmir –g mirdg query

ON THE TARGET HOST SUN5 Unless the relation is split target volume can’t be mounted on the target host 7) Mount the BCV volume on the target a) Scan for new disks sun5# vxdisk scandisks b) Now check the disk groups sun5#vxdisk –o alldgs list c) Import the disk group sun5# vxdg –C import sundg e) Start the volume Sun5#vxvol –g sundg startall f) Create amount point Sun5# mkdir BCV g) Mount the volume Sun5#mount /dev/vx/dsk/sundg/vol01 /BCV h) Open the directory sun5#cd BCV I) check the contents Sun5#ls (IF THE DATA EXISTS THE OPERATION IS SUCCESSFUL) Unmount the volumes on the target for later sync cycles Sun5#cd Sun5#umount BCV

Incremental mirror the volumes While BCV is split from standard volume, Some I/O may take place in the standard volume, Which results in the invalid tracks on BCV,so it is required to resync with Standard device again to have the tracks copied, so now perform incremental establish and check the data on the target volume. ON THE SOURCE SUN7 1) Add some data on source(Source has been already mounted on a directory BCV) a) Check the present working directory Sun7#pwd b) If the directory is not opened ,open the directory Sun7#cd bcv c) Add some data Sun7#cp /etc/f* . d) Check the status of the mirror Sun7#symmir –g mirdg query (Invalid tracks should be shown) e) Now synchronize incrementally (Check whether the target is unmounted) Sun7#symmir –g mirdg est (By default est does incremental copy of tracks) f) Check the mirror status Sun7#symmir –g sundg query (Invalid tracks should be Zero) g) Split the volumes and check the targets for data upgrades Sun7#symmir –g mirdg split –consistent h) Check the status Sun7#symmir –g mirdg query 2) ON THE TARGET SUN5 CHECK THE DATA a) Mount the volume Sun5#mount /dev./vx/dsk/sundg/vol01 /bcv b) Change to directory bcv sun5# cd bcv c) Now check the data in the directory Sun5# ls (IF THE UPDATED DATA IS SEEN YOUR OPERATION IS SUCCESSFUL)

RESTORE THE DATE TO SOURCE FROM TARGET In the source volume entire data has been erased now restore the data from the target ON THE SOURCE VOLUME SUN7 a) Check the present working directory Sun7#pwd

(if it is bcv leave it intact else)

b) Change the directory to BCV Sun7#cd BCV c) Remove the content in the volume Sun7#rm –rf * . d) check the data Sun7#ls (It should not have any content) e) Now unmount the volume Sun7#cd Sun7#umount bcv f) Now deport the dg Sun7#vxdg –C deport sundg CHECK THE STATUS ON THE TARGET SUN5 a) Unmount the volume Sun5# cd Sun5#umount bcv b) Deport the volume Sun5#vxdg –g deport sundg RESTORE THE DATA ON THE SOURCE SUN7 a) Execute restore command on the source Sun7#symmir –g mirdg restore b) Check the status Sun7#symmir –g mirdg query (Status should display restored) c) Import the disk group Sun7# vxdg –C import sundg d) Start the volume Sun7#vxvol –g sundg startall e) Mount the volume

Sun7#mount /dev/vx/dsk/sundg/vol01 /bcv f) Change the directory Sun7# cd BCV g) Check the content Sun7#ls IF THE DATA IS AVAILABLE AND IS SIMILAR TO THE PREVIOUS DATA THAT WAS DELETED BY US THEN THE OPRATION IS SUCCESS