[Beowulf] Which do you prefer local disk installed OS or NFS rooted?

[Tim Mattox]

Hello,
You missed a 3rd option, a RAMdisk as rootfs.  For many years I've done
diskful clusters and nfsroot clusters.  The RAMdisk approach is
head and shoulders above the other two approaches.

Check out Warewulf at http://warewulf-cluster.org/ to see one good
approach for doing RAMdisks as the rootfs on the nodes.

Disclaimer: I liked Warewulf so much, I became one of its developers.

> What benefits and drawbacks have all of you seen by doing either?

The drawback to nfsroot is that the nodes are so dependent on the NFS
server, that they tend to fail or have problems if the server is rebooted
or is down for any length of time.

With Warewulf, I can do maintenance on the server while jobs are running
on the nodes, and if I'm careful, the parallel runs won't even notice the
server was gone for awhile.

There are other benefits to the Warewulf approach, but I'll leave that for
others to discuss...  Suffice to say that it's so much better that I'll never go
back to full OS installs or NFS root for clusters that I'll agree to sysadmin.
-- 
Tim Mattox - tmattox at gmail.com - http://homepage.mac.com/tmattox/