Letting Go Is Hard
Welcome to No Disk Nirvana
Tuesday, August 15th, 2006
Last month, I talked about what goes into cluster nodes. In particular, I tried to make it clear that diskless booting of cluster nodes doesn’t exclude hard drives from those nodes. You can still provide local storage and use the Network File System (NFS) to share files among all nodes. If you grasp this idea, you may mutter the word “Aha! ” as you read the next few pages. If a bulb fails to light, well, read the article again.
This month, in classic “Cluster Rant” style I want to push diskless booting even further and see where it goes. As you’ll see, there are important advantages gained by removing the distribution from your nodes. Moreover, there are some things you cannot accomplish installing a classic Linux distribution on every node. I won’t mention any diskless booting package in particular, but I’m mostly thinking about the Warewulf Toolkit (http://www.warewulf-cluster.org/) and The Scyld Beowulf Distribution (http://www.scyld.com/. Both have the nuts and bolts to accomplish what I describe below.
The Diskless Way
