EMC SnapView Snapshots
EMC Clariion Storage features EMC SnapView, a snapshot technology that facilitates near-instantaneous hot backups and rapid restores.
If you purchase the feature license from Zmanda (available at the Zmanda Network Downloads page), ZRM for MySQL includes an optional snapshot plugin that integrates with EMC SnapView to create consistent MySQL full backups. It creates temporary snapshots of the EMC SnapView volumes on which to perform a full backup. When snapshots are enabled, ZRM for MySQL can perform backups with minimal impact on MySQL applications. Database writes will be blocked only during snapshot creation, which typically takes less than a second regardless of database size.
This page describes the configuration of EMC SnapView snapshot backups, including requirements for the MySQL database.
MySQL Configuration Requirements
- Sudo privileges must be configured for mysql user on the MySQL server (see the next section). On Solaris platforms, this means the SMCsudo package must be installed.
- If you are backing up a remote MySQL server, the destination directory specified on the Backup Where page must exist on the MySQL server as well as the ZRM server. The MySQL backup user (OS-level) must have read/write permission to access this directory.
All MySQL data and logs must reside on Clariion storage.
Refer to EMC-supplied Clariion documentation for details on EMC SnapView .
The Clariion volumes are mounted on ZRM server (direct attached or SAN attached). ZRM user "mysql" should have permissions to read and write to the volumes.
Pre-conditions for Using EMC Snapview Snapshots
- The MySQL backup user must be granted sudo privileges to execute EMC commands on the MySQL server. Add a line similar to the following example to /etc/sudoers on the MySQL server:
mysql MySQLserver.mycompany.com Server>=NOPASSWD:/bin/mount,NOPASSWD:/bin/umount,NOPASSWD:/bin/df, \
NOPASSWD:/opt/Navisphere/navicli,NOPASSWD:/sbin/fdisk,NOPASSWD:/sbin/fuser
- where MySQLserver.mycompany.com is the fully-qualified domain name for the MySQL server. Note that if EMCcommands are installed in non-standard locations, the above example would not work without editing it to reflect the different paths. Please see KB article for more information on sudo configuration.
- All MySQL database files (data, log, indexes) must be stored in SnapView volumes to ensure consistency. If any of the files are not on SnapView volumes, a raw backup using mysqlhotcopy, or a logical backup using mysqldump will be taken based on the storage engines of the tables in each of the databases.
- EMC NaviSphere (including the navicli and naviseccli utility) is required, and must be installed on the MySQL server being backed up and the ZRM server. This software is not shipped with ZRM for MySQL; contact EMC to obtain these programs.
Configuring ZRM for MySQL to use EMC SnapView Snapshots
To activate use of EMC SnapView Snapshots, simply select the EMC SnapView Snapshot Type as the Backup Methodfrom the Backup How page:
- EMC Host
- Specify the fully qualified domain name or IP address of the Clariion storage system. This is a mandatory parameter as there is no default.
- Storage Group
- Specify the EMC/Clariion Storage Group that you want to add to the snapshot. This is a mandatory parameter as there is no default.
- Navicli Binpath
- The path to where navicli and naviseccli are stored. The default value is /opt/Navisphere/bin.
- Backup Type
- Choose the method of snapshot backup. The Standard (Copy) option specifies that the snapshot should be copied to a standard ZRM for MySQL backup archive. The Quick (No Copy) option specifies that the snapshot itself should be used as a near-line backup. Quick backups are convenient as they provide faster backups and restores, but because they remain on the MySQL server they do not protect against media or server failure. Note that if the quick option is specified, the compress and encrypt options are ignored. In addition, no checksums are performed, which means that quick snapshot backups cannot be verified. Quick snapshot backups may be converted to standard backups stored on the ZRM server using the Convert Backup option available from the Reports menu tab.
Fallback for Logical
If this field is set to yes and snapshot backup fails, the logical backup is attempted. Set the value to No if you do not want to do logical backup if there is a snapshot backup failure.
Remote MySQL Binary Path
Path to the MySQL commands on the MySQL server.
Binary Log Path
Location of binary logs on the MySQL server that are used for log incremental backups.