PHP Memcached Failover Setup Guide
To achieve automatic failover for Memcached master-slave replication, you can follow these steps:
- Set up Memcached master-slave replication: Configure Memcached on both the master server and the slave server, and replicate the data from the master server to the slave server. Utilize tools such as Memcached Repcached or Twemproxy to simplify this process.
- Monitor the main server’s status: By regularly monitoring the main server, you can determine if it is functioning properly. Monitoring tools like Nagios or Zabbix can be utilized for this purpose.
- The main server failure has been detected: in the event of main server failure, a switch operation needs to be triggered. This can be done by monitoring the response time of the main server, or by using Memcached monitoring commands (such as the stats command) to check the availability of the main server.
- Switching to a standby server: In the event of a primary server failure, the standby server can be promoted to the primary server and redirect client requests to the new primary server. Tools such as HAProxy or Keepalived can be used to automate this switch.
It is important to note that Memcached itself does not provide automatic master-slave failover functionality, so other tools are needed to achieve this. Additionally, the replication delay in master-slave setups may lead to data inconsistency issues, so it is essential to assess the situation and decide if additional synchronization measures are needed.
