The Mechanics of High Availability

The term “high availability” refers to a part of your infrastructure that has as close to 100 percent uptime as possible and is intended to offer uninterrupted access to this critical component. Sometimes it’s referred to as the “five 9s,” or 99.999 percent uptime.

If you don’t have continuous access to your databases, what happens to the rest of your systems that depend on this information? People couldn’t get their jobs done, applications would crash, help desk tickets would go through the roof, and customers might not be able to access client-facing resources.

High availability is one of those things that isn’t optional for an organization that wants to grow, expand and compete in today’s marketplace. Your database administration environment must offer reliable access, with downtime only occurring due to extraordinary circumstances or regularly scheduled maintenance periods. So how can you achieve this goal and meet the demands of a tech-forward company?

High Availability Tools for MySQL Databases

For this article, we’ll assume that you administer MySQL databases. You have several tools available that offer you high availability for your databases, ensuring access to crucial business data.

MySQL Group Replication uses group communication techniques and database replication, with group communication primitives, to accomplish this task. All the servers in the group have reliable messaging to eliminate a single point of failure. Even if one of the servers goes down, there is seamless failover to other replicated databases. This multi-master update-everywhere replication plugin uses automatic distributed recovery, group membership and conflict detection as its main feature set.

As you scale up and add new servers, you don’t have to devote precious resources to getting the databases replicated onto the new equipment. MySQL Group Replication automates this process and empowers your organization to execute rapid scaling strategies without compromising your data access.

This MySQL plugin has two operation modes. The Single-Primary mode designates one server as primary and gives it read-write capabilities. Every other server in the group is configured in read-only mode. Updates to the group occur on one server at a time, and if something happens to the current primary server, a remaining server moves into the primary group through an election process.

Multi-master mode differs by having all servers in read-write mode. Each one accepts updates, and an election process is not necessary.

Galera is another high availability solution for MySQL databases. It operates with a virtual synchrony QoS with the Totem Single-Ring Ordering protocol. This group communication system layer is proprietary, so you have limited migration options should you choose to use a different solution in the future.

Using an Experienced Managed Service to Get the Most Out of Your High Availability Tools

Whether you use MySQL Group Replication, Galera or another high availability solution, you need an experienced partner to get the most out of the solution you select. Datavail is a managed services company focused specifically on data management. We work with the leading technologies to help your organization achieve the high availability that you need for your most important data.

Let us help you choose the right MySQL high availability plugin and configure it to meet your company’s unique needs, so you can focus on other database administration tasks without having to worry about this deployment. For additional resources, please download our white paper: Features, Pros and Cons of MySQL Group Replication.