High Availability Architectures Overview

Evidian SafeKit

What are the different high availability architectures and the different software clusters with SafeKit?

Mirror cluster

File replication at byte level and failover in a SafeKit mirror cluster

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Farm cluster

SafeKit farm cluster with network load balancing and failover

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Farm+mirror cluster

SafeKit clustering with load balancing and mirroring

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Active/active cluster

SafeKit active active cluster with real-time replication

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N-1 cluster

SafeKit N-1 redundancy cluster

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How to build high availability clusters with SafeKit?

Use high availability modules

A high availability module is a customization of SafeKit for an application. There are two types of modules: the mirror module with real-time data replication and failover and the farm module with load balancing and failover.

If you deploy a mirror module on 2 servers, then you create a mirror cluster and if you deploy a farm module on N servers, then you create a farm cluster.

Several application modules can be deployed on the same servers. Thus, advanced clustering architectures can be implemented like those presented previously (farm+mirror, active/active, N-1).

What is a module?

In practice, an application module is a “.Safe” file (zip type) including:

1 - the configuration file userconfig.xml which contains:

  • names or physical IP addresses of the servers,
  • name or virtual IP address of the cluster,
  • file directories to replicate in real time (for a mirror module),
  • network load balancing criteria (for a farm module),
  • configuration of software and hardware failures detectors

2 - the scripts to start and stop the application.

Plug and play deployment of high availability modules

Once an application module is configured and tested with an application, deployment requires no specific IT skills:

  1. install application on 2 standard servers (physical or virtual),
  2. install the SafeKit software on both servers,
  3. install the application module on both servers.

SafeKit: an ideal solution for a partner application

This platform agnostic solution is ideal for a partner with a critical application and who wants to provide a redundancy and high availability option easy to deploy to many customers.

This clustering solution is also recognized as the simplest to implement by our partners.

SafeKit Modules for Plug&Play Redundancy and High Availability Solutions

SafeKit Modules for Plug&Play High Availability Solutions

Network load balancing and failover

Windows farm

Linux farm

Generic Windows farm   > Generic Linux farm   >
Microsoft IIS   > -
Apache   >
Amazon AWS farm   >
Microsoft Azure farm   >
Google GCP farm   >
Other cloud   >

Advanced clustering architectures

Several modules can be deployed on the same cluster. Thus, advanced clustering architectures can be implemented:

SafeKit High Availability Differentiators against Competition

Demonstrations of Redundancy and High Availability Solutions

SafeKit Webinar

This webinar presents in 2 minutes Evidian SafeKit.

In this webinar, you will understand SafeKit mirror and farm clusters.

Microsoft SQL Server Cluster

This video shows a mirror module configuration with synchronous real-time replication and failover.

The file replication and the failover are configured for Microsoft SQL Server but it works in the same manner for other databases.

Free trial here

Apache Cluster

This video shows a farm module configuration with load balancing and failover.

The load balancing and the failover are configured for Apache but it works in the same manner for other web services.

Free trial here

Hyper-V Cluster

This video shows a Hyper-V cluster with full replications of virtual machines.

Virtual machines can run on both Hyper-V servers and they are restarted in case of failure.

Free trial here

SafeKit Training


  1. Overview / pptx

    • Features
    • Architectures
    • Distinctive advantages
  2. Competition / pptx

    • Hardware vs software cluster
    • Synchronous vs asynchronous replication
    • File vs disk replication
    • High availability vs fault tolerance
    • Hardware vs software load balancing
    • Virtual machine vs application HA

Installation, Console, CLI

  1. Install and setup / pptx

    • Package installation
    • Nodes setup
    • Cluster configuration
    • Upgrade
  2. Web console / pptx

    • Cluster configuration
    • Configuration tab
    • Control tab
    • Monitor tab
    • Advanced Configuration tab
  3. Command line / pptx

    • Silent installation
    • Cluster administration
    • Module administration
    • Command line interface

Advanced configuration

  1. Mirror module / pptx

    • userconfig.xml + restart scripts
    • Heartbeat (<hearbeat>)
    • Virtual IP address (<vip>)
    • Real-time file replication (<rfs>)
  2. Farm  module / pptx

    • userconfig.xml + restart scripts
    • Farm configuration (<farm>)
    • Virtual IP address (<vip>)
  3. Checkers / pptx

    • Failover machine (<failover>)
    • Process monitoring (<errd>)
    • Network and duplicate IP checkers
    • Custom checker (<custom>)
    • Split brain checker (<splitbrain>)
    • TCP, ping, module checkers


  1. Support tools / pptx

    • Analyze snapshots
  2. Evidian support / pptx

    • Get permanent license key
    • Register on support.evidian.com
    • Call desk


  1. Technical documentation

  2. Presales documentation