{color:#172b4d}Starting with MySQL 5.5 and for higher versions, the default storage engine within mySQL has been set to be the InnoDB Storage Engine. {color}
With this change, a higher rate of failure in restores has been seen in the MySQL 5.7 and higher versions. This has been accounted to the {color:#172b4d}data consistency standards that InnoDB adheres to.{color} {color:#172b4d}The reason relates to how InnoDB works.{color} {color:#172b4d}A short version is, w{color}{color:#172b4d}hen an attempt to restore a database is made, internally an attempt to restore to a temporary MySQL instance is made. However, the{color} {color:#172b4d}temporary MySQL instance{color} {color:#172b4d}fails to start, when only partial databases are restored. This is due to the nature of InnoDB, where it looks for the other databases referenced in the logs, that were not restored. On failing to find the same, it fails to start the temporary instance.{color}
{color:#212529}MySQL has provided the innodb_force_recovery option, which{color} {color:#212529}instructs InnoDB to start up in a recovery mode, telling it to skip various portions of the InnoDB start-up process. However, this option can also be destructive, hence it is recommended to use this option carefully.{color} {color:#172b4d}Also, we recommend that if needed, start with a low value and{color} {color:#212529}increase it only as needed.{color}
{info:title=Note}
Due to the destructive nature, we have given the Control Panel Admin, the option to enable or disable this feature to end users. If enabled, then this option will be made available during a MySQL Restore.
{info}
h3. How to Restore MySQL databases with innodb_force_recovery option
1. Access the recovery point of your account backups. There are two options to access the Recovery Points:
a. [Access account backups via Direct Link]
b. [Access account backups via cPanel plugin]
2. Here, {color:#172b4d}you will be able to view all of their Recovery points that have been backed up. To the right of each recovery point, you will find the available options.{color}
{color:#172b4d}3. From these options, select the option{color} {color:#172b4d}{*}Browse Databases{*}{color}{color:#172b4d}. You will be provided with a page which presents all of the recoverable databases.{color}
{color:#172b4d}4. Go ahead and select the database that you want to restore. Click the restore button to start the restore process for the database.{color}
{color:#172b4d}5. If the{color} {color:#212529}innodb_force_recovery option has been enabled,{color}{color:#172b4d} by the Control Panel Admin, you will be provided a popup box, with the innoDB_force_recovery option and a drop-down to select the value. {color}
{info:title=Tip}{color:#172b4d}The default value of the{color}{color:#172b4d} {color}{color:#172b4d}drop-down{color}{color:#172b4d} is 0, and it is recommended to continue with this value.{color}
{color:#172b4d}However, if you need to set the value of the {color}{color:#212529}innodb_force_recovery option, this would be the location to do so. {color}{color:#172b4d} {color}{info}
{color:#212529}6. Once set, continue to follow the steps, as usual, to complete the database restore.{color}
With this change, a higher rate of failure in restores has been seen in the MySQL 5.7 and higher versions. This has been accounted to the {color:#172b4d}data consistency standards that InnoDB adheres to.{color} {color:#172b4d}The reason relates to how InnoDB works.{color} {color:#172b4d}A short version is, w{color}{color:#172b4d}hen an attempt to restore a database is made, internally an attempt to restore to a temporary MySQL instance is made. However, the{color} {color:#172b4d}temporary MySQL instance{color} {color:#172b4d}fails to start, when only partial databases are restored. This is due to the nature of InnoDB, where it looks for the other databases referenced in the logs, that were not restored. On failing to find the same, it fails to start the temporary instance.{color}
{color:#212529}MySQL has provided the innodb_force_recovery option, which{color} {color:#212529}instructs InnoDB to start up in a recovery mode, telling it to skip various portions of the InnoDB start-up process. However, this option can also be destructive, hence it is recommended to use this option carefully.{color} {color:#172b4d}Also, we recommend that if needed, start with a low value and{color} {color:#212529}increase it only as needed.{color}
{info:title=Note}
Due to the destructive nature, we have given the Control Panel Admin, the option to enable or disable this feature to end users. If enabled, then this option will be made available during a MySQL Restore.
{info}
h3. How to Restore MySQL databases with innodb_force_recovery option
1. Access the recovery point of your account backups. There are two options to access the Recovery Points:
a. [Access account backups via Direct Link]
b. [Access account backups via cPanel plugin]
2. Here, {color:#172b4d}you will be able to view all of their Recovery points that have been backed up. To the right of each recovery point, you will find the available options.{color}
{color:#172b4d}3. From these options, select the option{color} {color:#172b4d}{*}Browse Databases{*}{color}{color:#172b4d}. You will be provided with a page which presents all of the recoverable databases.{color}
{color:#172b4d}4. Go ahead and select the database that you want to restore. Click the restore button to start the restore process for the database.{color}
{color:#172b4d}5. If the{color} {color:#212529}innodb_force_recovery option has been enabled,{color}{color:#172b4d} by the Control Panel Admin, you will be provided a popup box, with the innoDB_force_recovery option and a drop-down to select the value. {color}
{info:title=Tip}{color:#172b4d}The default value of the{color}{color:#172b4d} {color}{color:#172b4d}drop-down{color}{color:#172b4d} is 0, and it is recommended to continue with this value.{color}
{color:#172b4d}However, if you need to set the value of the {color}{color:#212529}innodb_force_recovery option, this would be the location to do so. {color}{color:#172b4d} {color}{info}
{color:#212529}6. Once set, continue to follow the steps, as usual, to complete the database restore.{color}