Ganeti is a cluster virtualization management system based on Xen. In this tutorial I will explain how to create one virtual Xen machine (called an instance) on a cluster of two physical nodes, and how to manage and failover this instance between the two physical nodes.

This tutorial shows how to set up a two-node Apache web server cluster that provides high-availability. In front of the Apache cluster we create a load balancer that splits up incoming requests between the two Apache nodes. Because we do not want the load balancer to become another "Single Point Of Failure", we must provide high-availability for the load balancer, too.

Today's tutorial will be on the infamous Quorum disk. When I first setup my GFS2 shared Cluster of 3 nodes, I was quite impressed with the fact that 3 nodes were sharing the same file system. Now that everything was up and running, I wanted to see what would happen if I brought down, 2 out of the 3 nodes in the cluster.

Openfiler is a Linux based NAS/SAN application which can deliver storage over nfs/smb/iscsi and ftp. It has a web interface over that you can control these services. The cluster we build will consist of two nodes replicating each other and taking over services and storage in case of emergency.

Now that I am done with the implementation of RHE Cluster with GFS2, I now need to setup monitoring. As you all know, monitoring is a vital part of any environment. Even though we have a cluster of nodes setup, we still need to be aware of what is happening. I created two new commands. The first command is to emulate clustat, but through python and SNMP.

This tutorial provides step-by-step instructions about how to create a highly available VMware Server environment on a Debian Etch system. With this tutorial, you will be able to create Virtual Machines that will be available on multiple systems with failover/failback capabilities.

If you have multiple servers with similar or identical configurations (such as nodes in a cluster), it's often difficult to make sure the contents and configuration of those servers are identical.

If a server goes down, essential services don't have to shut down along with it. To prevent downtime, Linux administrators can set up a Heartbeat cluster on Linux. Heartbeat adds the advantage of a cluster to Xen virtual machines (VMs), thus maintaining VMs' uptime when a server crashes.

In my last column, I mentioned the idea of disposable HPC. The concept is based on building clusters using low cost nodes (less than $500 each). Because lower cost nodes will run slower and have less cores than the big server nodes, they would need to be smaller and use much less power. They will also need a lowerThermal Design Power (TDP) to accommodate dense packaging designs.