SPP high availability


My question is.
Is it possible to create a cluster of 2 SPPs to use the high availability features?
In the documentation are reported solutions to 3 or more appliances.
My aim is to use a cluster of 2 SPP appliances in HA. Connected to 2 SPS already in high availability.
Are there any special instructions to follow?


Thanks for your help

  • Hi Armando

    The simple answer to your question is no. The SPP cluster operation requires a minimum of 3 appliances for correct operation.

    While a cluster of 3 appliances will tolerate the failure of a single appliance (effectively giving you the configuration you are looking for) this is not a supported configuration.

    SPP operations require "Consensus" or "Quorum" to operate correctly and this is where the requirement for an odd number of cluster members comes from.

    Quorum is based on a voting algorithm with each node in the cluster having a vote. The cluster keeps working while more than half of the voters are online.

    A Cluster Quorum configuration specifies the number of failures that a cluster can support in order to keep working.
    So SPP appliances have to be deployed in odd numbers. Hence supported configurations are 3 or 5 Node Clusters.

    Best regards


  • Hi Tim,

    Can I then create a 3-node cluster even if an appliance is located in another region? For example 2 nodes in Frankfurt and one in Turin?


  • Hi Armando

    Yes this is possible as long as you can meet the network requirements to ensure that cluster communications are not affected. You can find details of the requirements in the documentation.

    Also in a two site deployment it is recommended that you should deploy the Primary and a Replica in the DC creating the most traffic with the single SPP on the far site.

    You can enable Offline working to allow the single appliance at the remote site to continue to provide passwords in the event of a network outage. Again the documentation will give you details of this.

    Best regards