Switchover

This topic describes the primary/standby switchover procedure. You can choose one of the following switchover methods based on the business needs:

• Method 1: Perform a switchover for a specified primary tenant.
• Method 2: Perform a switchover for all primary tenants in a cluster.

Method 1: Perform a switchover for a specified primary tenant

You can switch a specified primary tenant to a standby tenant.

Prerequisites

The current primary tenant has at least one standby tenant in the Running state.

Procedure

1. Log on to the OceanBase Cloud Platform (OCP) console. In the left-side navigation pane, click Tenants. In the tenant list, select the target primary tenant to go to its basic information page.

2. Click the More icon in the upper-right corner and select Routine Switch from the menu.

3. In the dialog box that appears, confirm the information and click Start Switch.

   • If the primary tenant has multiple standby tenants, you must select a standby tenant for the switchover from the New Primary Tenant drop-down list.

   • If the synchronization mode of the selected standby tenant is Archiving-based and archiving is not enabled for the standby tenant, you must first configure an archiving address. The following table describes the parameters for configuring an archiving address.

     Parameter	Description
     Storage Type	The type of the storage medium for backup files. Valid values: File: indicates the local file storage system, which is generally Network File System (NFS). OSS: indicates Alibaba Cloud Object Storage Service (OSS), which is supported only in OceanBase Database V2.2.76 and later.
     Storage Directory	The directory where the backup files are stored on the medium. Note The primary and standby tenants must have the read/write privileges on this directory.
     Domain	If you select OSS for Storage Type, enter the access domain name of the OSS bucket. You can append a port number to the domain name, such as oss.ap-shanghai.myqcloud.com:8080.
     User	If you select OSS for Storage Type, enter the username used to access the OSS bucket.
     AccessKey Pair	If you select OSS for Storage Type, enter the AccessKey pair for accessing the OSS bucket.

4. Click the task ID in the dialog box to view the task progress.

Method 2: Perform a switchover for all primary tenants in a cluster

If you require standby tenants to provide services to ensure service continuity during the O&M of a cluster, you can switch all primary tenants in this cluster to standby tenants before the O&M.

Prerequisites

You have created primary tenants in the current cluster, and the primary tenants have available standby tenants.

Procedure

1. Log on to the OCP console. In the left-side navigation pane, click Clusters. On the Clusters page, go to the Overview page of the target cluster.

2. Click the More icon in the upper-right corner and select Routine Tenant Switch from the menu.

3. In the dialog box that appears, select the tenants for which you want to perform a switchover and click Daily Switch.

   • If a primary tenant has multiple standby tenants, you must select one of the standby tenants as the new primary tenant from the New Primary Tenant drop-down list.

     Before you perform a switchover, the system will check the primary and standby tenants against the following conditions. If the check fails, you cannot perform a switchover for the selected tenants.

     • The primary and standby tenants are in the Running state.
     • The clusters of the primary and standby tenants are in the Running state and are of the same version.
     • The synchronization latency of the standby tenant does not exceed the threshold, which is 5,000 ms by default. You can choose System Management > System Parameters and change the value of ocp.standby.tenant.delay.threshold to adjust the threshold.

   • If the synchronization mode of the selected standby tenant is Archiving-based and archiving is not enabled for the standby tenant, you must first configure an archiving address. The following table describes the parameters for configuring an archiving address.

     Parameter	Description
     Storage Type	The type of the storage medium for backup files. Valid values: File: indicates the local file storage system, which is generally NFS. OSS: indicates Alibaba Cloud OSS, which is supported only in OceanBase Database V2.2.76 and later.
     Storage Directory	The directory where the backup files are stored on the medium. Note The primary and standby tenants must have the read/write privileges on this directory.
     Domain	If you select OSS for Storage Type, enter the access domain name of the OSS bucket. You can append a port number to the domain name, such as oss.ap-shanghai.myqcloud.com:8080.
     User	If you select OSS for Storage Type, enter the username used to access the OSS bucket.
     AccessKey Pair	If you select OSS for Storage Type, enter the AccessKey pair for accessing the OSS bucket.

   Note

   This operation may cause the cluster where the new primary tenant resides to be overloaded. Proceed with caution.

4. Click the task ID in the dialog box to view the task progress.