A synchronous approach to multi-master replication in the M-Vault directory server
Traditionally LDAP servers have implemented multi-master using an asynchronous eventual convergence model where changes are propagated across the network of servers and any conflicting changes resolved automatically, if possible.
The specific requirements of Isode’s customers were that changes be reflected in the entire replication network immediately and without delay, and so a multi-master model where changes are replicated synchronously was chosen. The benefits to the approach are twofold; that changes to the data at any node are immediately available to all clients connected to the service and that, in the absence of network partition, conflicting changes cannot be applied to the data.
This talk will provide an overview of the synchronous multi-master approach, covering the pros and cons of the design and also on future directions for improvement of the solution.
Damy Mahl is the lead engineer for the Isode M-Vault directory server product set. Prior to his involvement with M-Vault Damy worked at Brunel University on a number of directory related projects, including some of the earliest directory user agents and white pages services.