vpruthi/doc-exports
1
0
Fork 0
forked from docs/doc-exports
Code Pull Requests Activity
doc-exports/docs/dcs/umn/dcs-faq-0730058.html
Chen, Junjie 748ac2c008 DCS UMN 20230811 version 
Reviewed-by: Mützel, Andrea <andrea.muetzel@t-systems.com>
Co-authored-by: Chen, Junjie <chenjunjie@huawei.com>
Co-committed-by: Chen, Junjie <chenjunjie@huawei.com>
2024-01-24 14:13:13 +00:00

2.2 KiB
Raw Blame History

When Does a Master/Standby Switchover Occur?

A master/standby switchover may occur in the following scenarios:

  • A master/standby switchover operation is initiated on the DCS Console.
  • If the master node of a master/standby instance fails, a master/standby switchover will be triggered.

    For example, running commands that consume a lot of resources, such as KEYS commands, will cause CPU usage to spike and as result triggers a master/standby switchover.

  • If you restart a master/standby instance on the DCS console, a master/standby switchover will be triggered.
  • If you scale up a single-node or master/standby instance, a master/standby switchover will be triggered.

    During scale-up, a new standby node with the new specifications is created. After full and incremental data on the master node is synchronized to the standby node, a master/standby switchover is performed and the original node is deleted.

After a master/standby switchover occurs, you will receive a notification. Check whether the client services are running properly. If not, check whether the TCP connection is normal and whether it can be re-established after the master/standby switchover to restore the services.