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Galera Cluster

Multi-master cluster for MySQL

Galera Cluster offers database clustering and high availability with synchronized multi-master replication for MySQL and MariaDB.

Galera Cluster

Multi-Master Cluster Management

Galera Cluster ist eine leistungsfähige Open-Source-Software für Datenbank-Clustering und Hochverfügbarkeit. Es basiert auf der Galera-Replikationstechnologie und wurde speziell für Datenbanken wie MySQL und MariaDB entwickelt. Das Ziel von Galera Cluster ist es, eine synchronisierte Multi-Master-Replikation zu ermöglichen, bei der mehrere Knoten als aktive Datenbankmaster fungieren und Änderungen in Echtzeit auf alle anderen Knoten repliziert werden.


High-availability database environments

Galera Cluster provides synchronized multi-master replication for databases like MySQL and MariaDB. The main features are high availability, real-time synchronization, scalability, conflict resolution, rolling upgrades and zero downtime schema changes. It enables the uninterrupted operation of databases even in the event of node failures and always ensures up-to-date data on all nodes.


Synchronized multi-master replication

Galera Cluster enables real-time and synchronized replication of databases on multiple nodes. Any node can act as a master and changes to the data are automatically and instantly replicated to all nodes.

High Availability

Galera Cluster offers high availability because there is no single point of failure. If one node fails, the remaining nodes automatically take over processing the requests without the database failing.

Active-Active Architecture

Each node in the Galera Cluster is an active participant and can process both read and write operations. This allows the load to be distributed across all nodes, improving database scalability and performance.

Conflict resolution

Galera Cluster provides conflict resolution for concurrent write operations on different nodes. In the event of a conflict, a rule is automatically applied to prioritize transactions and ensure database consistency.

Rolling Upgrades

Galera Cluster enables rolling upgrades, where nodes can be upgraded one at a time without impacting database availability. This is particularly useful for maintenance and upgrades to new versions of the database.

Zero downtime schema changes

Galera Cluster supports zero-downtime schema changes, so database schemas can be changed without downtime. This enables flexible and efficient management of the database structure.


The components of Galera

Galera Cluster architecture is based on Galera replication technology and is designed to enable synchronized multi-master replication for databases.

Cluster Nodes

Each node in the Galera Cluster is a standalone database instance that acts as an active participant. All nodes are interconnected and communicate via a network protocol to exchange changes to the databases.

Galera Replication

Galera Cluster uses the WSREP (Write Set Replication) protocol to enable real-time replication of the databases. WSREP captures the write operations (Write Set) on one node and replicates them to all other nodes in the cluster.

Quorum Mechanism

Galera Cluster uses a quorum mechanism to ensure consistency and availability. A cluster requires a majority of nodes (quorum) to remain functional and perform write operations. If the majority of nodes fail, the remaining node goes into read-only mode.


Gcache (Galera Cache) is a cache that records writes and replicates them to other nodes to improve replication performance and efficiency. The RingBuffer file used for this is predefined when the server is started.


To initialize a new node or synchronize with the cluster, Galera Cluster uses either IST (Incremental State Transfer) or SST (State Snapshot Transfer). IST only transfers the changes since the last state, while SST transfers a complete record from an active node.


Galera Cluster Consulting

We help you with the conception, installation and integration of your environment – for more power, know-how, peace of mind!


Years of experience

We have been supporting our customers in operating their IT infrastructures for many years. Industries, tools, operating systems – we’ve seen, operated and built everything. We know the best practices with MySQL, Galera, MariaDB & Co. and many topics related to Open Source and Linux.

Know How

Full Understanding

We not only understand your IT systems and services, but the big picture and the countless aspects of operating complex IT infrastructures. There is often a lack of time and personnel with increasing complexity and a rapidly changing IT world.

Peace of Mind

Targeted Reinforcement

As Linux generalists and open source experts, we have a broad base and are well integrated into the open source communities. With us you are never alone! Whether as an IT consultant, engineer, support or architect – we strengthen your team and relieve you of work.

Everything from a single source

The holistic portfolio of NETWAYS

You need support with the planning, implementation and operation of Galera Cluster. NETWAYS supports you in all matters relating to consulting, outsourcing and, of course, training.

IT Outsourcing

As an external IT department, we take over the complete operation of entire environments. We take care of all the necessary systems from the open source world and work with you.


With us you get quick help from your personal systems engineer. Whether by phone, chat, email or ticket: we are always there for you! Galera not doing what it’s supposed to? Get in touch with us!


We are happy to pass on our extensive and profound practical knowledge to you in our training courses and workshops. Of course, as face-to-face and of course online training.


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