Showing posts with label SYMMMIR. Show all posts
Showing posts with label SYMMMIR. Show all posts

SRDF Pair Status

Posted by Diwakar ADD COMMENTS

SRDF/S and SRDF/A configuration involves tasks such as suspending and resuming the replication, failover from R1 side to R2, restoring R1 or R2 volumes from their BCV, and more. You perform these and other SRDF/S or SRDF/A operations using both symrdf and TimeFinder command symmir. The below details are for SRDF Pair states during SRDF procedure.

SyncInProg :- A synchronization is currently in progress between the R1 and the R2. There are existing invalid tracks between the two pairs and the logical link between both sides of an RDF pair is up.

Synchronized :- The R1 and the R2 are currently in a synchronized state. The same content exists on the R2 as the R1. There are no invalid tracks between the two pairs.

Split :- The R1 and the R2 are currently Ready to their hosts, but the link is Not Ready or Write Disabled.

Failed Over :- The R1 is currently Not Ready or Write Disabled and operations been failed over to the R2.

R1 Updated :- The R1 is currently Not Ready or Write Disabled to the host, there are no local invalid tracks on the R1 side, and the link is Ready or Write Disabled.

R1 UpdInProg :- The R1 is currently Not Ready or Write Disabled to the host, there are invalid local (R1) tracks on the source side, and the link is Ready or Write Disabled.
Suspended :- The RDF links have been suspended and are Not Ready or Write Disabled. If the R1 is Ready while the links are suspended, any I/O accumulates as invalid tracks owed to the R2.

Partitioned :- The SYMAPI is currently unable to communicate through the corresponding RDF path to the remote Symmetrix. Partitioned may apply to devices within an RA group. For example, if SYMAPI is unable to communicate to a remote Symmetrix via an RA group, devices in that RA group are marked as being in the Partitioned state.

Mixed :- Mixed is a composite SYMAPI device group RDF pair state. Different SRDF pair states exist within a device group.

Invalid :- This is the default state when no other SRDF state applies. The combination of R1, R2, and RDF link states and statuses do not match any other pair state. This state may occur if there is a problem at the disk director level.

Consistent :- The R2 SRDF/A capable devices are in a consistent state. Consistent state signifies the normal state of operation for device pairs operating in asynchronous mode.

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

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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
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