What is the method for Hadoop active-standby failover?
The switch between primary and backup in Hadoop can be achieved through the following methods:
- Utilizing Automatic Failover: Hadoop has a feature that allows automatic failover, enabling a standby node to automatically switch to become the primary node when the main node fails. This requires setting up a monitoring process to track the status of the main node and trigger the switch operation in the event of a failure.
- Manual switch: If you do not use the automatic failover function, you can also manually switch between primary and backup nodes. This requires the administrator to manually switch the backup node to the primary node. The specific operation can be completed by shutting down the primary node service, adjusting the backup node to the primary node, and then restarting the service.
Whether using automatic failover or manual switch, it is important to ensure the consistency and reliability of data during the transition process. This can be achieved by techniques such as replicating data to backup nodes or using distributed file systems like HDFS to guarantee data redundancy and reliability.
It is important to note that the process of switching between primary and backup systems may result in some service interruptions, so caution should be taken during the switching operation to minimize the impact on users as much as possible.
