Upgrade overview

OceanBase Database supports cluster upgrades by using upgrade scripts. During the upgrade process, applications are not affected, and no write or service stoppage operations are required on the server side. OceanBase Database upgrades clusters in the order of zones. During the upgrade, the partition leader actively switches between zones and redirects the business traffic of the zone to be upgraded to other zones for execution.

This topic describes the upgrade process, considerations, limitations, and impacts of upgrading an OceanBase cluster.

Limitations

OceanBase Database has the following limitations during an upgrade:

• DDL operations are disabled during the upgrade. They are enabled after the upgrade is completed.
• The major freeze operation is disabled during the upgrade. It is enabled after the upgrade is completed.
• Migration replication and load balancing are disabled during the upgrade.
• Physical backup and restore are disabled during the upgrade. Physical baseline backup (log archiving continues) and physical restore are not initiated.
• New tenants cannot be created during the upgrade.

Considerations

During the upgrade of an OceanBase cluster, consider the following points:

• Log archiving is disabled during the upgrade from OceanBase Database V4.0 to V4.1.

• If the ADD SERVER or DELETE SERVER operation is required during the upgrade, contact technical support.

• You cannot directly upgrade an OceanBase transitional version. You must follow the upgrade sequence specified in the oceanbase_upgrade_dep.yml file.

• You must directly connect to the observer process that hosts the Root Service to run the upgrade script. You cannot connect to the Root Service through OceanBase Database Proxy (ODP).

• The following parameters may change during the upgrade. Back up these parameters before you upgrade the cluster:

  • server_permanent_offline_time
  • enable_rebalance
  • enable_rereplication

• Starting from OceanBase Database V4.2.2, OceanBase Database no longer supports the zlib_1.0 compression algorithm. During the upgrade, the following checks are performed:

  • The zlib compression algorithm is no longer supported as the value of the log_transport_compress_func parameter. You must use another compression algorithm instead of the zlib compression algorithm.
  • If some tables use the zlib compression algorithm during the upgrade, you must replace the compression algorithm of these tables with another supported compression algorithm, or disable compression during the upgrade.
  • The zlib compression algorithm is no longer supported as the compression algorithm for Table API connections. You must set the table_api_transport_compress_func parameter to specify another compression algorithm.

• When you upgrade a V4.x cluster to a V4.2.5 or later cluster, the standby tenant of the lower version cluster cannot parse the logs generated by the higher version cluster. In this case, an error is returned when the standby tenant submits logs (the error is not persisted to logs).

• If the cluster contains a large number of tablets, the restart of the OBServer process during the upgrade may take a long time. For example, if the cluster contains more than 3 million tablets, the restart may take about 20 minutes. In such a case, you must reserve sufficient time for the upgrade.

• Starting from OceanBase Database V4.2.5 BP3, V4.2.5 BP4, V4.2.5 BP5, V4.3.5 BP1, V4.3.5 BP2, and V4.3.5 BP3, the instruction set requirements for X86 architecture environments are added. Before the OBServer process starts, it checks whether the current environment supports the AVX instruction set. If the AVX instruction set is not supported, the OBServer process cannot start. If you upgrade the OBServer process of an X86 server that does not support the AVX instruction set to the above versions, the OBServer process cannot start and cannot be rolled back. Pay attention to this issue.

  Note

  Starting from the following versions, OceanBase Database no longer requires the AVX instruction set:

  • Starting from V4.3.5 BP4, the AVX instruction set is no longer required for V4.3.5.
  • Starting from V4.2.5 BP6, the AVX instruction set is no longer required for V4.2.5.
  • Starting from V4.4.1, the AVX instruction set is no longer required for V4.4.0.

• You cannot restore a backup of OceanBase Database V4.3.2 to OceanBase Database V4.3.3.

Version compatibility

• You can upgrade an OceanBase cluster of a version earlier than V4.2.1 BP10 to V4.2.5 BP7 by first upgrading it to V4.2.1 BP11.
• You can upgrade an OceanBase cluster of V4.2.2 to V4.2.5 BP7 by first upgrading it to V4.2.2.1.
• You can directly upgrade an OceanBase cluster of V4.2.3, V4.2.4, or V4.2.5 to V4.2.5 BP7.

Upgrade path

The following table describes the upgrade path:

• For V4.2.x versions:

  • A V4.0.0.0, V4.1.0.0, V4.1.0.2, or V4.2.0.0 version can be upgraded to a V4.2.1.11 version, and then further to a V4.2.5.7 version.
  • A V4.2.2 or V4.2.4 version can be upgraded to a V4.2.5.7 version directly, or upgraded to a V4.2.5.0-V4.2.5.6 version first, and then further to a V4.2.5.7 version.
  • Barrier versions: V4.2.1.11 and V4.2.5.7.

• For V4.3.x versions:

  • All V4.3.x versions can be upgraded to a V4.3.5.5 version.
  • Upgrading from V4.2.x or earlier versions to V4.3.x versions is not supported.

• For V4.4.x versions:

  • A V4.4.0, V4.4.0.1, or V4.4.1 version can be upgraded to a V4.4.2 version.
  • A V4.2.5 BP7 version can be upgraded to a V4.4.2 version.

What to do next

Upgrade OceanBase cluster

Reference

For information about how to upgrade an OceanBase cluster on OceanBase Cloud Platform (OCP), see Upgrade version.