Server services are the roles in the Scalability module:
- Apcahe – web server;
- Memcached – data caching;
- MySQL - database;
- Sphinx – full text search.
Note: One more role is available on the main server of the pool, the Balancer, which is a system role managing all the servers and services of the pool.
When hovering over a role, the menu with the option Add a role appears:
Following the execution of the role adding wizard (it may take a long time), the page will be loaded and a role selected on this server will be displayed.
The procedure to Delete role is similar:
When creating a role MySQL slave the system will prompt you to create a back-up copy of the database:
If you select OK at this stage, the page of Back-up copy will open; if you choose Cancel, the creation of the role MySQL slave will be continued.
Once the MySQL role is added, this base will play the role of a slave base, i.e. data will be written to the master base and read from the slave base, thus the workload between these databases will be split.
In order to change the role MySQL slave to MySQL master, select Make master in the action menu of the role MySQL slave:
Thus, the new simple tool Scalability permits creating a server pool with the necessary roles, monitoring, and workload distribution using the steps described above.
The execution of the commands may take a rather long time (from one minute to 2-3 hours and more) depending on the complexity of the task, volume of data used in these tasks, and server capacity and workload. During the execution of the command, other functionality will be unavailable, and a warning about it will be displayed.