[Discuss] HA storage

[tmetro+blu at gmail.com (Tom Metro)]

Derek Martin wrote:
>  - provide redundant, replicating data storage (expensive: think
>    redundant replicating disk array, such as the expensive solutions
>    EMC provides for this purpose)
>  - connect your storage to all of the nodes in your cluster
> 
> The only hard part is paying for the redundant storage.  My now-
> defunct former employer was developing a (relatively) cheap solution
> that replaced the expensive EMC array with cheaper redundant RAID
> arrays, but that product was subsumed by Red Hat.

Rich Braun wrote:
> I'm posting this after a frustrating 24 hours with old technologies
> AoE (ATA over Ethernet)...  AoE comes up OK but by itself
> accomplishes nothing beyond a collection of universally accessible
> raw disk blocks.

How about iSCSI? Is that any more solid on Linux than AoE?

You'll still need a clustering file system to layer on top if you're are
going to have multiple storage nodes, which is assumed. I guess once
you've take on that complexity, then there is less to be gained by
separating your storage nodes from your compute nodes (from an HA
perspective; may still make sense from a performance perspective).

(The old way to address this was with a dual-headed NAS, but clustering
file systems with multiple nodes seems to be the way the cloud providers
are heading. Software is cheaper than hardware...)

 -Tom

-- 
Tom Metro
The Perl Shop, Newton, MA, USA
"Predictable On-demand Perl Consulting."
http://www.theperlshop.com/