Re: active/active vs active/passive?

[Paul Clements <paul.clements@steeleye.com>]

Dan Stromberg wrote:
> The lecturer at the recent NG storage talk at Usenix in Anaheim,
> indicated that it was best to avoid "active/active" and get
> "active/passive" instead.
> 
> Does anyone:
> 
> 1) Know what these things mean?

In the clustering world, active/active means 2 or more servers are 
active at a time, either operating on separate data (and thus acting as 
passive failover partners to each other), or operating on the same data 
(which requires the use of a cluster filesystem or other similar 
mechanism to allow coherent simultaneous access to the data).

> 2) Know why active/passive might be preferred over active/active?

Well, if you're talking about active/passive vs. active/active with a 
cluster filesystem or such, the active/passive is tons easier to 
implement and get right. Plus, depending on your application, the added 
complexity of a cluster filesystem might not actually buy you much more 
than you could get with, say, NFS or Samba (CIFS).

--
Paul