[UPHPU] load balanced file-based sessions

[Lonnie Olson]

On Tue, 2008-05-06 at 11:21 -0600, Wade Preston Shearer wrote:
> > Storing sessions on an NFS share is usually your only choice.
> 
> What are the downsides to this? The mount failing? anything else?

Even worse performance than local disk storage, mount failing, network
performance impact, etc.

> > Unless you can configure your load balancer to map to servers by  
> > source
> > IP, and not randomly.
> 
> This is one of the options that I was exploring. If I can keep the  
> user on the same node, then I can keep file-based sessions on that web  
> server and everything will be peachy. Are there any downsides to this?

If a node dies, that group of users will lose their sessions and
possibly connectivity too depending on the quality of the load balancer.

> How would a SAN work?

A SAN is a special separate network, usually FiberChannel or iSCSI, that
can share hard disks to several servers at once.  Very expensive startup
costs, but very reliable and fast.

--lonnie