SnapProtect - Overview - MySQL iDataAgent

Overview Deployment Deployment - UNIX Configuration Select Storage Array
Backup Vault or Mirror Copy Backup Copy Restore  

SnapProtect backup enables you to create a point-in-time snapshot of the data used for backups. An effective way to back up live data is to quiesce it temporarily, take a snapshot, and then resume live operations. SnapProtect backup works in conjunction with storage arrays to provide snapshot functionality for backup.

You can use the SnapProtect backup to perform full backups for MySQL iDataAgent. When you switch from a snap to a traditional backup or vice-versa, the next job is converted to a full backup. While performing an SnapProtect backup or any subsequent operations, you can use a proxy server to reduce the load on the production server. Also, the backup copy operation will use the proxy to move the snap to backup media. Proxy server is supported with hardware storage arrays.

The following illustration describes the process involved in SnapProtect backup:

Advantages of Using SnapProtect Backup

The traditional dump backups run based on the queries on the database server. During this backup operation, depending on the storage engine used, the tables might be locked for the entire duration of the backup operation. If the database size is huge, the load and availability of the server for the clients might get affected.

You can overcome this issue by performing the SnapProtect backup for MySQL. In this case, the snap backups lock the tables only for few seconds during the snapshot creation, irrespective of the storage engine used. With the SnapProtect technology, we can create backups of huge databases within few seconds.

The following table lists some of the advantages of using SnapProtect backup over other available backup solutions.

Feature Support Generic Software Solution SnapProtect SnapProtect Backup
Backup to Tape
Hardware Agnostic - No dependency on the hardware array vendor changes  
Snapshot copy, backup copy, and tape copy creation and management are seamless. Application aware snapshots creation can be scheduled. The snapshots can be cataloged/indexed for restore and Backup Copy based on policies.  
To reduce load on the production server, a proxy server can be used for operations like Backup Copy, integrity check.  
Restores can be performed directly from media to the application server.  
Ability to mix and match SnapProtect backup with traditional backups. You can perform full SnapProtect backups combined with incremental log backups being moved to media and still perform a seamless restore.  
All data management operations can be performed from the CommCell Console.  

Advantages of Using SnapProtect Backup with MySQL

SnapProtect backups of MySQL provide the following additional benefits:

  • Ability to backup large databases (in tera and peta bytes) within few minutes.
  • To obtain consistent backup, the snap backups lock the tables only for a few seconds during the snapshot creation, irrespective of the storage engine used.
  • Transaction log backups enable you to recover the database to any specific point-in-time.
  • The files can be backed up to tape or magnetic library.
  • Fast recovery using application aware revert operation.
  • Ability to schedule backups.
  • Ability  to restore from media to a database server, either directly or through a temporary location.

Overview of SnapProtect Backup Operation

The SnapProtect backup includes the following operations:

Backup job is scheduled from the CommCell Console. When the backup job is started:

  • List of paths where databases, innodb files are located is determined.
  • List of physical disks that correspond to the datafiles is determined.
  • The database server is put in a quiesce mode using the following command:

    flush tables with read lock;

  • A snapshot copy of the volume is created.
  • Transaction log file and offset is queried using the following command:

    show master status;

  • The quiesce mode is stopped using the following command:

    unlock tables;

  • Index of file entries relevant in the snapshot are created and stored in the ctree tables.
  • The ctree index tables are archived.

SnapProtect Backup on Solaris Zones

In a Solaris Zone environment, the SnapProtect backup includes the following operations:

Backup job is scheduled using the CommCell Console. When the backup job is started:

  • The local zone collects the list of mounts/volumes to be included in the SnapProtect backup.
  • The local zone sends the request to the global zone to create a snapshot for the required volumes.
  • The array is accessed from the global zone to create the snapshot.
  • The snapshot is mounted on the proxy or (global zone) source computer for post backup operations.
  • The snapshot is unmounted.

SnapProtect Backup Copy

The SnapProtect Backup Copy Operation is supported using the File System Backup Copy.

File System Backup Copy

During File System Backup Copy operations:

  • The job type is always FULL.
  • The snapshot is mounted.
  • The snap device is cloned and Volume Group/Logical Volumes are automatically created to mount the snapshot.
  • The Index created during snap is queried to identify files to backup to tape and generates collect file for backup copy.
  • The files are backed up to tape or magnetic library .
  • The Snapshot is unmounted.
  • The index created for backup copy operations are archived.

Terminology

The SnapProtect Backup documentation uses the following terminology:

Storage Device A device used for backup or archival purposes.
Storage Array A high-end disk storage system. The SnapProtect software is designed to work in conjunction with the snapshot ability built into the storage array.
Proxy A computer other than the production server on which you can perform SnapProtect operations. A proxy  is used to decrease the load on the production server.
Snapshot Copy An additional copy of the protected data that is used in SnapProtect operations.