Changing Read/Write Permissions

Scenarios

RDS for MySQL allows you to change the read/write permissions of your instance to meet different workload requirements. You can select Read-only or Read/write for Read/Write Permissions.

• Read-only

  If Read-only is selected, data in the DB instance cannot be modified anymore. You can set Read/Write Permissions to Read-only even for a DB instance that is already read-only due to full storage. In this case, after the instance becomes available, it is still read-only.

• Read/write

  If Read/write is selected, the DB instance becomes readable and writable. You can set Read/Write Permissions to Read/write even for a DB instance that is read-only due to full storage. In this case, only after the instance becomes available, it is readable and writable.

Constraints

• This function is only available for single and primary/standby DB instances.
• Read/write permissions cannot be changed when the instance is in any of the following statuses: creating, changing instance class, frozen, or abnormal.
• This function is available for open beta testing (OBT) in some regions. If this function is not available in your region, contact customer service to request permissions.

Precautions

• Before setting Read/Write Permissions to Read-only, to ensure data consistency, ensure that no data is being written to the database.
• If the DB instance is abnormal (except when the storage is full), it cannot be set to read-only.
• If your instance is set to read-only, you can still perform operations on the Accounts and Databases pages on the console.
• If your instance is set to read-only, non-administrator users cannot write data to it anymore. When your instance is processing large transactions or DDL requests, changing it to read-only may fail due to timeout.
• If your RDS instance is associated with a DDM instance, changing it to read-only will affect DDM instance functions.
• If you have selected Read/write but the DB instance is still read-only, check whether the DB instance is involved in an ongoing DRS migration task or if the instance storage is full.
• If your instance becomes read-only for other reasons (such as full storage and DRS migration), it cannot be changed to readable and writable by setting Read/Write Permissions to Read/write.
• This function configures read/write permissions only for primary DB instances.

Procedure

1. Log in to the management console.
2. Click in the upper left corner and select a region and a project.
3. Click in the upper left corner of the page and choose Databases > Relational Database Service.
4. On the Instances page, click the instance name.
5. In the DB Information area on the Basic Information page, click Change next to the Read/Write Permissions field. In the displayed dialog box, select Read-only or Read/write as required and click OK.
   Figure 1 Changing read/write permissions