Configuring High Availability

written by vdbdev on August 26, 2013 with no comments

VoltDB, when running on multiple hosts, can tolerate the failure of one or more hosts and continue running. To accomplish this, the database replicates partitions to multiple servers within a cluster. As long as at least one copy of each partition is available, the database can continue operation.

To enable high availability you must add some configuration to the deployment.xml file to specify the desired number of extra copies of each partition, your k-factor. The database will store k+1 copies of each partition. The default k-factor is 0.

Here is a simple deployment file that stores two extra copies of each partition.

<?xml version="1.0"?>
<deployment>
    <cluster hostcount="1" sitesperhost="2" kfactor="2" />
    <httpd enabled="true">
        <jsonapi enabled="true" />
    </httpd>
</deployment>

More Information

For more on availability in VoltDB, see the Availability chapter of Using VoltDB.