[Beowulf] SATA II - PXE+NFS - diskless compute nodes

[John Hearns]

Joe Landman wrote:
> 
> Guy Coates wrote:
> 
>> At what  node count does the nfs-root model start to break down?  Does anyone
>> have any rough numbers with the number of clients you can support with a generic
>> linux NFS server vs a dedicated NAS filer?
> 
> If you use warewulf or the new perceus variant, it creates a ram disk
> which is populated upon boot.  Thats one of the larger transients.  Then
> you nfs mount applications, and home directories.  I haven't looked at
> Scyld for a while, but I seem to remember them doing something like this.
> 

I've booted up and run a 130 node cluster in ramdisk mode, with 
applications shared over NFS. I ran HPL benchmarks for the client across 
all nodes in the cluster in this configuration.
That's 130 Sun galaxy 4200s, the head node being a Galaxy 4200 also in 
this case.
I agree with what Joe says about a few hundred nodes being the time you 
would start to look closer at this approach.

> 
> Even better if you can load balance your NFS servers and set them up to
> mirror each other, or use a hardware unit like Panasas, and so on.
Second that.

-- 
      John Hearns
      Senior HPC Engineer
      Streamline Computing,
      The Innovation Centre, Warwick Technology Park,
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