Access Server Admin Guide: Cluster Configuration
About the Page
The Configuration: Cluster page allows you to define the settings for the Access Server within a cluster architecture. If you have not installed a MySQL client in your server, you will not be able to configure the settings but will instead receive the message as seen below. If you wish to configure your server as a cluster of nodes, please read the Setting Up an OpenVPN Access Server Cluster guide.
The Cluster Page for an Access Server without a MySQL client installed.
Please refer to Setting up an OpenVPN Access Server cluster for more information about installing the MySQL client into your server and how to set up the necessary database. Once you have completed this setup, you are now ready to use this UI to finalize and synchronize your new cluster nodes.
The Cluster Page for an Access Server with a MySQL client installed.
Cluster Setup
To configure the Access Server as clusters, you can create a new cluster or join an existing cluster.
Selecting either option displays the following sections:
Node Name
A setting for Status display. You define the name for the cluster node that will display in the GUI. You have the option to give this whatever identifier you prefer.
MySQL Settings
Recalling the Setting Up an OpenVPN Access Server Cluster guide, you were required to set up a MySQL database. The guide provides step-by-step instructions for setting up an Amazon RDS database. This section assumes that you leave the default port as 336 and encourages you to record the Endpoint, Master Username, and Master Password. These credentials will be what you input respectively.
It is not required that you use Amazon RDS nor is it required that your port is 336. You have the option to use any MySQL compatible database (i.e MySQL, Amazon RDS, MariaDB). As long as you have the necessary credentials and the correct port, you can use these for the Cluster Configuration.
Inter-node communication Settings
It is necessary to set up an internal channel for inter-node communication to occur in the Cluster. This setup requires an IP/Hostname and a port. By default, Inter-node communication uses the same hostname that the VPN Server listens for VPN clients; the port used is 945. However, if there is an internal IP/hostname for this node, then Inter-node communication can be configured to use that instead. Make sure that the port you are using is open.
More Options For a New Cluster
When you have selected Setup a New Cluster, found in the Cluster Setup section, a few sections should appear at the bottom of the page.
Additional sections for setting up a new cluster:
Global cluster client connection endpoint
This is the default DNS hostname used when a client attempts to connect to an Access Server node. Unless specified in the configuration for a particular cluster node, this hostname will be used for the Round-Robin DNS, which chooses a semi-random cluster node for the client to connect to.
Cluster-wide Profile
When creating a new cluster, this defines a configuration profile you can use for additional nodes to inherit the same settings. The selected configuration settings can always be changed for each individual cluster. The selected profile only acts as the default setting when adding a new cluster or when settings are not defined for an existing cluster.
UI for a Cluster Access Server
The following UI fields are relevant to an Access Server that is part of a network of nodes.
After the Access Server has reset, the following header displays:
The side menu will have sections that are inaccessible. Certain settings can only apply to specific nodes while other settings apply to the entire Access Server as a whole.
Cluster Overview
These following changes in functionality now affect the Status Overview page. The name in the sub-menu remains the same but when you click it, you navigate to the Cluster Overview page. This page consists of a table listing relevant information for each node in the cluster.
Cluster Overview Table for a cluster with one node:
This table provides an overview of the node(s) while also providing an interface that allows executing actions on that particular node.
Status/Node Name
This column shows if the node is active and lists the general name of the node.
Clicking on the column will provide you with more information about the node.
Node IP Address Port
Displays the host IP address of the node and the port that it is using.
Version
Displays the version of the Access Server for the node (i.e 2.7.4, 2.6.1).
VPN Connections
Lists the total amount of VPN connections that the node is permitted to have based on the subscription purchased.
More Info
Clicking on this button displays additional information about the node. It is the same table provided when you click the node's name.
View Node
This button allows you to configure the settings of the specific node. Here, you can view the status of the node, view the current users, generate logs, and configure the routing settings. However, certain settings are unavailable such as Authentication since these are handled by the Cluster instead of the individual nodes.
Restart
Clicking on this button restarts the node.
Remove
Clicking on this button removes the node from the cluster.
Summary
Clustering gives you multiple Access Servers that communicate and act as a larger Server. It requires a configuration of a MySQL database with necessary information about the Access Server and it provides the information for when failover is necessary. When you have a successfully-configured cluster, your UI changes to reflect the new configuration. If you configure your Access Server as a network of clusters, certain settings pertain to individual nodes and other settings apply to the entire entity of the Access Server.