Cluster Software Installation

Highly Available, Scalable, Multi-tier Solution Architecture

Base packages

On both nodes, the following packages are the minimum that should be installed for the cluster exemplified in this document to function correctly:

  • rgmanager - Manages cluster resources defined by the user. It allows you to define services for high-availability on your cluster. Rgmanager monitors the services, and if a node fails, it will relocate the service to another node in the cluster.
  • cman - A symmetric, general-purpose, kernel-based cluster manager.
  • openais - The cluster manager (cman) locking scheme uses kernel modules to communicate cluster status and changes between nodes. OpenAIS uses userspace programs to accomplish the same thing.

In some setups, other Red Hat Clustering related packages may be required. Please consult the official Red Hat documentation portal and specific Clustering documentation for detailed instructions on how to install all the required packages for your specific case

To install the packages, please issue on all nodes involved in the cluster, the following command:

The openais package is automatically pulled by as a dependency of the cman package, so it's not necessary to specify it in the yum command line.

Cluster administration packages

Conga

Client (ricci)

The ricci package provides the client component of the Conga administrative interface needed to configure the cluster. It needs to be installed on all nodes involved in the cluster, using the command:

The modcluster package is automatically pulled by as a dependency of the ricci package.

The package also provides a daemon, which must be started via its corresponding initscript:

Server (luci)

The luci package provides the server component of the Conga administrative interface needed to configure the cluster. You can install it on any of the nodes involved in the cluster. In this example setup, we have installed it on the n1.cl.axilab.local node.

In order to install the luci package, please issue:

After installation, you need to set the password for the admin user needed to access the UI interface:

A (re)start is required for the password to be taken into account:

Then, the administrative interface can be accessed by typing into a browser the hostname or IP address of the node that contains the installed instance of the Conga web UI, via the secure https protocol on the 8084 port (default values).

Our specific example uses the https://n1.cl.axilab.local:8084 address to access the administrative interface.