What is the RTO / RPO of a SafeKit high availability cluster?

Evidian SafeKit

What is the recovery time (RTO) of a mirror cluster?

RTO is the time during which the application is unavailable in case of failure. RTO of the SafeKit mirror cluster is in the order of 1 mn and can be decreased if you configure the heartbeat timeout.

For a hardware failure, RTO = heartbeat timeout (default 30 s, can be changed in userconfig.xml) + time to restart the application.

For a software failure or an administrator restart, RTO = time to (cleanly) stop the application + time to restart it.

Be careful, with solutions that reboot a full virtual machine in case of failure, the RTO includes the reboot time of the virtual machine.

What is the data loss (RPO) of a mirror cluster?

RPO reflects the data loss in case of failure. RPO of the SafeKit mirror cluster is 0 as the replication is synchronous and real-time.

Be careful, with asynchronous replication, RPO is not 0 and there is data loss in case of failure when the application restarts on the secondary server.

What is the recovery time (RTO) of a farm cluster?

RTO is the time during which the application is unavailable in case of failure. RTO of the SafeKit farm cluster is in the order of a few seconds on hardware failure.

For a hardware failure, RTO = failure detection timeout through monitoring channels (default a few seconds): after the timeout the load balancing filters are reconfigured.

For a software failure or an administrator restart, RTO = time to (cleanly) stop the application + time to restart it.

What is the data loss (RPO) of a farm cluster?

N/R. A farm cluster does replicate any data.

SafeKit Modules for Plug&Play High Availability Solutions

What are the advantages of a mirror cluster?

  • Low Complexity
  • Plug&Play deployment with no specific skills
  • Suitable for large deployments in many sites (very simple to deploy)
  • 2 physical or virtual nodes
  • No shared storage requirement
  • No Domain Controller requirement
  • Same solution on Windows and Linux
  • Support Windows Server and Client OS editions
  • Well documented API and support
  • Synchronous data replication (no data loss in case of failure)
  • Replicated directories can be in the system disk
  • Supports multiple heartbeats and vitual IP addresses
  • Offers configurable software, hardware and network checkers
  • For the split brain problem and the quorum, does not require a special disk or a third machine or a dedicated link between both servers
  • Automatic failover of application with a recovery time in the order of one minute
  • Automatic failback when a server comes back after a failure (no manual operation)
  • A very simple console to deploy the solution and to maintain it afterwards for end-customer
  • Supports hardware and environment failures (20% of causes of unavailability), including the complete failure of a computer room with 2 nodes in two remote sites
  • Supports software failures (40% of causes of unavailability): software bug, regression on software update (N and N+1 versions can coexist)
  • Supports human errors (40% of causes of unavailability) : the simplicity of use avoids the administration error of the critical application

What are the advantages of a farm cluster

  • Low Complexity
  • Plug&Play deployment with no specific skills
  • Suitable for large deployments in many sites (very simple to deploy)
  • 2 physical or virtual nodes or more
  • No network load balancers requirement
  • No proxy server requirement (above the farm cluster)
  • No Domain Controller requirement
  • No restriction in VMware due to multicast or unicast address
  • Same solution on Windows and Linux
  • Support Windows Server and Client OS editions
  • Well documented API and support
  • Supports multiple monitoring channels on multiple networks for server failure detection
  • Supports multiple vitual IP addresses
  • Offers configurable software, hardware and network checkers
  • Offers the mirror cluster with synchronous real-time replication and failover to implement a farm+mirror 3-tiers architecture
  • Automatic failover with a recovery time in the order of a few seconds
  • Automatic failback when a server comes back after a failure (no manual operation)
  • A very simple console to deploy the solution and to maintain it afterwards for end-customer
  • Supports hardware and environment failures (20% of causes of unavailability), including the complete failure of a computer room with 2 nodes in two remote sites
  • Supports software failures (40% of causes of unavailability): software bug, regression on software update (N and N+1 versions can coexist)
  • Supports human errors (40% of causes of unavailability): the simplicity of use avoids the administration error of the critical application

SafeKit High Availability Differentiators against Competition

Demonstrations of SafeKit High Availability Software

SafeKit Webinar

This webinar presents in 10 minutes Evidian SafeKit.

In this webinar, you will understand:

  • mirror and farm clusters
  • cost savings against hardware clustering solutions
  • best use cases
  • the integration process for a new application

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