First Steps

To run the demo cluster you will need a cluster enabled VMware Server version. You may download and apply for a free license key on VMware's web site: http://www.vmware.com/download/server/

Please ensure that your VMware host machine meets following requirements:

• 2GHz class CPU
• At least 256MB (Better: 512MB and more) physical memory for each virtual machine.
• Enough disk space to store the virtual machines for the demo cluster (3GB)
  
• Additional free disk space (2-3GB) to allow paging and dynamic resizing of the disks.
• Optional: internet connection if you want to update the installed packages,
• Linux as operating system (ideal: RHEL, CentOS, Fedora)
  

After you have downloaded the images, you should place them in a seperate hierarchy in the default directory for virtual machines, e. g.  /var/lib/vmware/Virtual Machines/shared-root-cluster exactly as they are stored on our server.

If you select a different directory you have to adjust the location for your virtual disks.

Please make sure that you do not create a new UUID or change the MAC address of the virtual machines. The MAC addresses are configured in the cluster.conf and determine the node id.

On some VMware setups there is an issue with virtual network interfaces that are configurated as NAT. You may try bridged if you have any problems.

Last Update of the VMware Images: 2007/07/08

Diskless Shared Root Cluster

The demonstration Diskless Shared-root Cluster includes following files (~2.9GB):

• http://download.atix.de/comoonics-images/vmware/shared-root-cluster/host1/host1.vmx
  Host configuration file for host1. Please note, that this host has no local disks and boots from a shared virtual disk.
• http://download.atix.de/comoonics-images/vmware/shared-root-cluster/host2/host2.vmx
  Host configuration file for host2. Please note, that this host has no local disks and boots from a shared virtual disk.
• http://download.atix.de/comoonics-images/vmware/shared-root-cluster/shared-boot/shared-boot.vmdk
  Virtual disk that emulates a shared disk which would be located in the SAN. It is formated with ext3 and is used to boot the comoonics boot-image.
  
• http://download.atix.de/comoonics-images/vmware/shared-root-cluster/shared-root/shared-root.vmdk
  http://download.atix.de/comoonics-images/vmware/shared-root-cluster/shared-root/shared-root-s001.vmdk
  http://download.atix.de/comoonics-images/vmware/shared-root-cluster/shared-root/shared-root-s002.vmdk
  http://download.atix.de/comoonics-images/vmware/shared-root-cluster/shared-root/shared-root-s003.vmdk
  http://download.atix.de/comoonics-images/vmware/shared-root-cluster/shared-root/shared-root-s004.vmdk
  http://download.atix.de/comoonics-images/vmware/shared-root-cluster/shared-root/shared-root-s005.vmdk
  Virtual disk (that emulates a shared disk which would be located in the SAN. It is formated with Red Hat's Global File System (GFS) and includes the shared root directory for all the cluster nodes.
• http://download.atix.de/comoonics-images/vmware/shared-root-cluster/isos/CentOS-4.4.ServerCD-i386.iso
  CentOS Server ISO used to install the cluster. You may want to optionally download this file if you want to follow the workshop instructions step by step.

After you load the virtual machines in the inventory of your VMware Server you can boot them. You will receive further instructions at the Linux login prompt. Please note, that you will have to type in YES when you get asked wether the cluster is in a quorate state at first boot. Then a new cluster will be formed and the other node may join.

If also the other node wants to form a new cluster there is a mistake in VMware's network configuration or maybe you block the traffic with your firewall rules.

While internet connection is optiona, the cluster nodes have to share the same cluster communication network.

The cluster setup includes a High Availability configuration for Apache and can be used as NFS Server with pseudo load balancing.

If you need more information please do not hesitate to contact us. If you want to learn how to setup and work with a Diskless  Shared Root Cluster you may want to visit a clustering workshop or look into the documentation on this site.

We are offering workshops at major Linux fairs or you can book us for inhouse training of your staff. See http://www.atix.de/events to see upcoming events.