Table of Contents
Functionality and architecture
Libraesva ESG 5.3 introduces a new Distributed Setup deployment composed of up to 66 nodes capable of managing the heaviest mail flows.
Distributed setup is composed of a master-master cluster and up to 64 worker nodes:
The distributed setup supports geographic placement of nodes, providing extra high availability and load balancing across different datacenters. Both the master nodes and each worker can be placed in a different geographical datacenter.
The master nodes are used to configure, manage and monitor all the worker nodes. All workers will inherit the same configuration from the master nodes and are all identical.
Each worker receives, analyses and delivers email messages, all the information about messages processed by workers is consolidated to the cluster.
You can easy add new worker nodes from admin area > high availability > setup as worker.
How to upgrade all nodes
The upgrade procedure follows the same steps as a simple cluster.
You can start the update from one of the master nodes and the workers will be automatically updated to the latest version available.
Quarantine management
All quarantined messages are consolidated into the master cluster.
Workers maintains only the current and the previous day of quarantined messages. The web console of each worker allows to manage the quarantine messages stored on the same node.
How to manage mail flow
With the standard DNS load balancing, every worker IP address is published in the MX record.
Technically the two master nodes are also capable of receiving and processing email but this configuration is discouraged except during the migration process from a two-nodes cluster to a distributed setup.