[CentOS] OT: Caching synchronous writes

Fri Apr 23 00:10:37 UTC 2010
Ray Van Dolson <rayvd at bludgeon.org>

On Thu, Apr 22, 2010 at 03:50:11PM -0700, John R Pierce wrote:
> Ray Van Dolson wrote:
> >> I think what you want is a proper storage array with mirrored write
> >> cache.
> >>     
> >
> > Which is what we have with ZFS + SSD-based ZIL for far less money than
> > a NetApp.
> >   
> not unless you have a pair of them configured as an active/standby HA 
> cluster, sharing dual port disk storage, and some how (magic?) mirroring 
> the cache pool so that if the active storage controller/server fails, 
> the standby can take over wthout losing a single write.

This is definitely tangental to what I was originally asking. :)

I'm not suggesting this perfectly replaces (or even comes close) a
clustered NetApp setup.  But it can provide similiar NFS write
performance and I can buy three of them and replicate data for DR needs
for far less than the price of a NetApp SnapMirror setup.