On Friday, February 22, 2013, Jared Biel wrote:
> > As a counter argument though, anyone running a C* cluster on the Amazon > cloud is going to be using SAN storage (or some kind of proprietary storage > array) at the lowest layers...Amazon isn't going to have a bunch of JBOD > running their cloud infrastructure. However, they've invested in the > infrastructure to do it right. > > This is certainly true when using EBS, however it's generally not > recommended to use EBS when running Cassandra. EBS has proven to be > unreliable in the past and it's a bit of a SPOF. Instead, it's recommended > to use the "instance store" disks that come with most instances (handy > chart here: http://www.ec2instances.info/). These are the rough > equivalent of local disks (probably host level RAID 10 storage if I'd have > to guess.) > > -Jared > > On 22 February 2013 00:40, Michael Morris <michael.m.mor...@gmail.com>wrote: > > I'm running a 27 node cassandra cluster on SAN without issue. I will be > perfectly clear though, the hosts are multi-homed to different > switches/fabrics in the SAN, we have an _expensive_ EMC array, and other > than a datacenter-wide power outage, there's no SPOF for the SAN. We use > it because it's there, and it's already a sunk cost. > > I certainly would not go out of my way to purchase SAN infrastructure for > a C* cluster, it just doesn't make sense (for all the reasons others have > mentioned). Any more, you can load up a single 2U server with multi-TB > worth of disk, so the aggregate storage capacity of your C* cluster could > potentially be as much as a SAN you would purchase (and a lot less hassle > too). > > As a counter argument though, anyone running a C* cluster on the Amazon > cloud is going to be using SAN storage (or some kind of proprietary storage > array) at the lowest layers...Amazon isn't going to have a bunch of JBOD > running their cloud infrastructure. However, they've invested in the > infrastructure to do it right. > > - Mike > > > On Thu, Feb 21, 2013 at 6:08 PM, P. Taylor Goetz <ptgo...@gmail.com>wrote: > > I shouldn't have used the word "spinning"... SSDs are a great option as > well. > > I also agree with all the "expensive SPOF" points others have made. > > Sent from my iPhone > > On Feb 21, 2013, at 6:56 PM, "P. Taylor Goetz" <ptgo...@gmail.com> wrote: > > Cassandra is designed to write and read data in a way that is optimized > for physical spinning disks. > > Running C* on a SAN introduces a layer of abstraction that, at best > negates those optimizations, and at worst introduces additional overhead. > > Sent from my iPhone > > On Feb 21, 2013, at 6:42 PM, Kanwar Sangha <kan...@mavenir.com> wrote: > > Ok. What would be the drawbacks J**** > > ** ** > > *From:* Michael Kjellman [mailto:mkjell...@barracuda.com] > *Sent:* 21 February 2013 17:12 > *To:* user@cassandra.apache.org > *Subject:* Re: Cassandra with SAN**** > > ** ** > > No, this is a really really bad idea and C* was not designed for this, in > fact, it was designed so you don't need to have a large expensive SAN.**** > > ** ** > > Don't be tempted by the shiny expensive SAN. :)**** > > ** ** > > If money is no object instead throw SSD's in your nodes and run 10G > between racks**** > > ** ** > > *From: *Kanwar Sangha <kan...@mavenir.com> > *Reply-To: *"user@cassandra.apache.org" < > >
