Overview

OceanBase Database allows you to upgrade a cluster by using an upgrade script. The upgrade process is transparent to applications, so you do not need to stop or suspend your applications or services. OceanBase Database upgrades zones in sequence. During the upgrade, the system performs an active leader switchover between zones and diverts the business in the zone to be upgraded to other zones.

This topic describes the upgrade limitations, considerations, and paths of OceanBase Database.

Limitations

When upgrading OceanBase Database, keep in mind the following limitations:

• DDL is disabled: DDL is disabled during some stages of the upgrade. It will be automatically enabled after the upgrade is completed.
• major freeze is disabled: The major compaction is disabled during the upgrade. It will be automatically enabled after the upgrade is completed.
• Replication and load balancing are disabled: During the upgrade from some versions, replication and load balancing are disabled.
• Physical backup and restore are disabled: Physical baseline backup (log archive) and restore are disabled during the upgrade. However, ODP is not affected.
• Tenant creation is disabled.

Considerations

When upgrading OceanBase Database, keep the following considerations in mind:

• Log archive is disabled during the upgrade from V4.0 to V4.1.
• If an ADD SERVER/DELETE SERVER operation is needed during the upgrade, contact a technical expert for support.
• You cannot directly upgrade a transitional version. Refer to the upgrade version sequence in the oceanbase_upgrade_dep.yml file.
• The upgrade script must be executed directly on the observer process where the Root Service is located. It cannot be connected to through OceanBase Database Proxy (ODP).
• Back up the following parameters before the upgrade, as they may be modified during the upgrade:
  • server_permanent_offline_time
  • enable_rebalance
  • enable_rereplication

Upgrade paths

OceanBase Database supports an upgrade path from V4.0.0.0 to V4.1.0.0.

Upgrade process

The upgrade script for upgrading OceanBase Database V4.x depends only on the Python scripts in the RPM package of the target version. In other words, if the target version is V4.1.0 or later, only one upgrade process applies, and only the OceanBase RPM package of the target version is required. After decompressing the OceanBase RPM package, you will find the oceanbase_upgrade_dep.yml file, which records the version upgrade topology of OceanBase Database.

Upgrade notes

• An online upgrade from V3.x to V4.x is not supported.
• You can use OMS to migrate data from V3.x to V4.1.
• An online upgrade from V4.0 to V4.1 is supported.

Next steps

Start the upgrade

References

• server_permanent_offline_time
• enable_rebalance
• enable_rereplication