1. Associate the BCV Device for pairing: To perform standard/BCV pairing, the standard and BCV mirror devices of your production images must be members of the same device group (Note:- Already discussed in previous post about creating device group and pairing devices). symbcv –g DgName –sid SymmID associate dev 0ABC BCV001 Or to associate a range of devices to a device group, enter: symbcv –g DgName –sid SymmID associateall dev –RANGE 0ABC:0DEF Note:- -sid SymmID is optional if you have already defined device group in symcli environment varaiable. 2. Unmount the BCV device: Prior to using devices for BCV operations, the BCV device should be Windows formatted and assigned a drive letter. If using basic disks on the Windows platform, you must unmount the BCV devices. If using dynamic disks, you must deport the entire TimeFinder device group. For basic disks, use the syminq command to determine the SymDevName of the potential BCV device. For dynamic disks,use the TimeFinder symntctl command to determine the volume and disk group name as follows: symntctl list –volume [dg DgName] Note that the term device group and dynamic disk group are the same applied to this command. Unmount the selected BCV device as follows (with TimeFinder command): symntctl unmount –drive z Where z equals the designated drive letter. If an error occurs, check for an “openhandle” and clear this condition. For Veritas dynamic disks only, you must deport the disk group and rescan using the following commands: vxdg deport –g DgName symntctl rescan 3. Fully Establish BCV and STD: To obtain a copy of the data on a standard device, the BCV device of the pair must be established. To initiate a full establish on a specific standard/BCV device pair, target the standard device: symmir –g DgName –full establish DEV001 Fully Establish all pairs in a group. To initiate a full establish on all BCV pairs in a device group, enter: symmir –g DgName –full establish Verify the completed (synchronized) establish operation. To verify when the BCV pairs reach the full copied or Synchronized state, use the verify action as follows: symmir –g DgName –i 20 verify With this interval and count, the message is displayed every 20 seconds until the pair is established. Rescan the drive connections. For Dynamic disks only on a Windows host, you should rescan for drive connections visible to the host: symntctl rescan After any standard/BCV pair has been fully established and subsequently split, to save establish (resync) time, you can perform an establish operation omitting the -full option, which updates the BCV copy with only the changed tracks that occurred on the standard device during the elapsed BCV split time. To perform an incremental establish, omit the –full option, targeting the standard device symmir -g DgName establish DEV001 Optionally, you can also collectively target all devices in a device group, composite group, or defined devices in a device file: symmir –g DgName establish [-full] symmir –g CgName establish [-full] symmir –file FileName establish [-full] 4. Prepare (freeze) Production database for a TimeFinder Split: To prepare to split the synchronized BCV device from the production standard device, you must suspend I/O at the application layer or unmount the production standard prior to executing the split operation. symioctl freeze –type DbType [object] Ensure any residual cache on the Production host is fully flushed to disk. To insure all pending unwritten production file system entries are captured, enter TimeFinder command: symntctl flush –drive z Wait 30 to 60 seconds for the flush operation to complete. 5. Split the BCV devices: To split all the BCV devices from the standard devices in the production device group, enter: symmir –g DgName split To split a specific standard/BCV pair, target the logical device name in the group, enter: symmir –g DgName split DEV001 6. Verify the split operation completes: To verify when the BCV device is completely split from the standard, use the verify action as follows: symmir –g DgName –i 20 verify –split -bg With this interval and count, the message is displayed every 20 seconds until the pair is split. 7. Rescan for dynamic disks: For dynamic disks only, you should rescan for drive connections visible to the host: symntctl rescan 8. Mounting BCV device: After splitting the BCV device, you can mount the device with captured data on another host and reassign the drive letter. For basic disks, use the TimeFinder command: symntctl mount –drive z –dg DgName For Dynamic disks, use the TimeFinder command: symntctl mount –drive z –vol VolName –dg DgName | -guid VolGuid For VERITAS dynamic disk only, you must deport the disk group and rescan, as follows: vxdg deport –dg DgName symntctl rescan For Dynamic disk only (without Veritas), you can use the Microsoft diskpart command to select the disk and import the device using the online and import actions. Note:- symntctl command available in TimeFinder/IM ( Integration Module).
of the pair:
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The EMC provided solution to this problem is called “Enginuity Consistency Assist”. When you create a set of sessions and invoke Enginuity Consistency Assist, the Symmetrix aligns the I/O of those devices and halts all I/O from the host systems very briefly—much faster than the applications can detect—while it creates the session. It then resumes normal operation without any application impact.
TimeFinder Consistent Split using (TimeFinder/Consistency Groups) allows the splitting off of a consistent, re-startable image of an Oracle database instance within seconds with no interruption to the online Oracle database instance.
- Allows users to split off a dependent write consistent, re-startable image of application without interrupting online services
- Using TimeFinder/Consistency Groups to defer write I/O at the Symmetrix before a split
- Consistent split can be performed by any host running Solutions Enabler connected to the Symmetrix
- Tested and available including HP-UX, Solaris, AIX, Linux, and Windows
- No database shutdown or requirement to have database put into backup mode (Oracle).
Using TF/CG, consistent splits helps to avoid inconsistencies and restart problems that can occur with using Oracle hot-backup mode (not quiescing the database).
• No disruption to the online Oracle database to obtain a Point-in-Time image
• Provides a consistent, re-startable image of the Oracle database for testing new versions or database patch updates before deploying for use in production environments
• Can be used to obtain a business point of consistency for business restart requirements for which Oracle has been identified as one of multiple databases for such an environment.
The same benefits apply using TF/CG in a clustered environment as in a non-clustered environment:
- No disruption to the online Oracle database to obtain a Point-in-Time image in a Oracle single instance environment or when using Oracle Real Application Clusters
- Provides a consistent, re-startable image of the Oracle database for testing new versions or database patch updates before deploying for use in clustered production environments
- Can be used to obtain a business point of consistency for business restart requirements for which Oracle has been identified as one of multiple databases for such an environment.
TimeFinder/Clone creates full-volume copies of production data, allowing you to run simultaneous tasks in parallel on Symmetrix systems. In addition to real-time, nondisruptive backup and restore, TimeFinder/Clone is used to compress the cycle time for such processes as application testing, software development, and loading or updating a data warehouse. This significantly increases efficiency and productivity while maintaining continuous support for the production needs of the enterprise.
¨ Ability to protect Clone BCVs with RAID-5
¨ Create instant Mainframe SNAPs of datasets or logical volumes
for OS/390 data, compatible with STK SNAPSHOT for RVA.
¨ Facilitate more rapid testing of new versions of operating systems, data base managers, file systems etc., as well as new applications Load or update data warehouses as needed
¨ Allow pro-active database validation, thus minimizing exposure to faulty applications.
¨ Allows multiple copies to be retained at different checkpoints for lowered RPO and RTO, thus improving service levels.
¨ Can be applied to data volumes across multiple Symmetrix devices using EMC’s unique consistency technology (TimeFinder/Consistency Group option required).
I am going to discuss about TimeFinder BCV Split operation where Host running on Oracle Database. This split operation is different from normal BCV split operation. There are differences in command as well. Thats reason I am putting steps for this:
The following steps describes splitting BCV devices that hold a database supporting a host running an Oracle database. In this case, the BCV split operation is in an environment without PowerPath or ECA. The split operation described here suspends writes to a database momentarily while an instant split occurs. After an establish operation and the standard device and BCV mirrors are synchronized, the BCV device becomes a mirror copy of the standard device. You can split the paired devices to where each holds separate valid copies of the data, but will no longer remain synchronized to changes when they occur.
The Oracle database is all held on standard and BCV devices assigned to one Oracle device group.
1) Check device status on the database BCVs
To view and check status of the database BCV pairs, use the following form:
symmir –g DgName query
Check the output to ensure all BCV devices listed in the group are in the synchronized state
2) Check and set the user account
For SYMCLI to access a specified database, set the SYMCLI_RDB_CONNECT environment variable to the username and password of the system administrator’s account. The export action sets this variable to a username of system and a password of manager, allowing a local connection as follows:
export SYMCLI_RDF_CONNECT=system/manager
The ORACLE_HOME command specifies the location of the Oracle binaries and the ORACLE_SID command specifies the database instance name as follows:
export ORACLE_HOME=/disks/symapidvt/oraclhome/api179
export ORACLE_sid=api179
You can test basic database connectivity with the symrdb command as follows:
symrdb list –type oracle
3) Backup the database
For safety, perform a database hot backup. For example:
symioctl begin backup –type oracle –nop
4) Freeze the database
For safety, perform a freeze on the database I/O. For example:
symioctl freeze –type oracle –nop
This command suspends writes to the Oracle database.
5) Split all BCV devices in the group
To split all the BCV devices from the standard devices in the database device group, enter:
symmir –g oraclegrp split –instant -noprompt
Make sure the split operation completes on all BCVs in the database device group.
6) Thaw the database to resume I/O
To allow writes to the database to resume for normal operation, enter:
symioctl thaw –type oracle –nop
7) End the backup
To terminate the hot backup mode, enter the following command:
symioctl end backup –type oracle –nop
About Me
- Diwakar
- Sr. Solutions Architect; Expertise: - Cloud Design & Architect - Data Center Consolidation - DC/Storage Virtualization - Technology Refresh - Data Migration - SAN Refresh - Data Center Architecture More info:- diwakar@emcstorageinfo.com