[2 days left] What’s wrong with your cloud strategy? Learn why multicloud solutions matter with Nimble Storage.Register Now


Advice about storage purchase decision - DAS vs NAS vs SAN

Posted on 2014-02-08
Medium Priority
Last Modified: 2016-11-23
Greetings and thanks in advance for taking the time to help us with this critical decision.

Currently we have: Windows 2008 Dell server connected by SAS cable to a MD3000 storage (DAS)
It works as a http server to server files that amounts to a total of 15TB so far.

We are running out of space quickly and need to act now.

The volume is at its maximum limit now due to the way it was formatted initially - so attaching a MD1200 to extend the storage wouldn't work (we'll not be able to extend the volume

We are evaluating if we should get the new unit to be NAS vs SAN vs DAS.

DAS seems the simplest of them all, least complex and the the one with least possibility of bad configuration.

It can support up to 8 servers connected with single cables.

So, would you recommend we switch to an ISCSI SAN, DAS or NAS?

I'll follow up with whatever details would help you give a relevant advice to our specific case.

Thanks again
Question by:Mohamed Hammad
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
  • 2
LVL 23

Assisted Solution

by:Patrick Bogers
Patrick Bogers earned 1000 total points
ID: 39844373

It depend on several things. A simple NAS which is attached to the network wont be fast enough to serve up to 8 servers simoultaniously.
DAS can, so could SAN but here the question lays "what is the budget?"

If budget is big and number of IOPS is very high i would say fibre optics and SAN.
If budget is not sufficient go for DAS.

Author Comment

by:Mohamed Hammad
ID: 39844468
If the budget is tight - would you recommend a cheaper SAN like the MD3xxi - or is it like, either an EqualLogic or better go to DAS?

We don't even have 8 servers yet - it is a single server which we aim to make high available by adding a 2nd.
LVL 23

Expert Comment

by:Patrick Bogers
ID: 39844476
If budget is an issue i would say more is better in terms of space.
So if the DAS solution has been performing ok there is no need for iscsi/fiber san.
Concerto's Cloud Advisory Services

Want to avoid the missteps to gaining all the benefits of the cloud? Learn more about the different assessment options from our Cloud Advisory team.

LVL 56

Expert Comment

ID: 39845093
DAS is cheapest but "It can support up to 8 servers connected with single cables." describes what most people would all a SAS attached SAN, not DAS. DAS is generally considered to be a dumb shelf connected to a RAID controller inside the server and is the cheapest and best solution for a single server.

The MD3000 is generally considered to be a SAS attached SAN as it's shared storage. Dell may describe it as DAS on their website but the real manufacturer describes it as SAN - http://www.netapp.com/uk/products/storage-systems/e2700/index.aspx (actually the MD3000 is LSI Engenio but they sold the range to NetApp who still make later versions for Dell, IBM etc).

You will not get better performance from a SAN than from a DAS, at least if you have the same disks in each. Why would separating the RAID controller from the server with a bit of fibre optic cable speed it up rather than plugging it directly into the PCIe bus?

As far as real DAS is concerned the MD1000 range of expansion enclosures run on Dell PERCs just as well as they run on MD3000s.

Author Comment

by:Mohamed Hammad
ID: 39845172
So what would you recommend David?

SAS attached SAN - MD ISCSI SAN - EqualLogic ISCSI SAN?

We would love to be able to remotely replicate the volumes to another site but I guess that can be done with a SAS attached SAN - right?
LVL 56

Accepted Solution

andyalder earned 1000 total points
ID: 39845178
I missed this bit - "We don't even have 8 servers yet - it is a single server which we aim to make high available by adding a 2nd."

If you're going to have two hosts attached to the same LUN with clustering an MD3000/3200 SAS attached SAN would be needed. There's no storage level replication though for a remote site, you would have to do that with software on one of the servers. www.visionsolutions.com/Products/DT-Avail.aspx would do that for you.

MD3260f does remote replication but that's a lot more expensive.

By the way, another slightly misleading description on Dell's site is the "up to 8 servers", it does indeed support 8 servers connected by SAS but because there are 4 ports on each controller you can only share a particular LUN between 4 servers, not that that will be a problem in your case.

Still can't quite see why you can't hang a couple of additional enclosures on your current MD3000. Even if you can't expand the current LUN due to some software restraint you can create another bigger LUN just like you would be doing with this new storage box.

Author Comment

by:Mohamed Hammad
ID: 39845607
It would work actually - thanks a lot :)

Featured Post

Learn Veeam advantages over legacy backup

Every day, more and more legacy backup customers switch to Veeam. Technologies designed for the client-server era cannot restore any IT service running in the hybrid cloud within seconds. Learn top Veeam advantages over legacy backup and get Veeam for the price of your renewal

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

AWS Glacier is Amazons cheapest storage option and is their answer to a ‘Cold’ storage service.  Customers primarily use this service for archival purposes and storage of infrastructure backups.  Its unlimited storage potential and low storage cost …
I previously wrote an article addressing the use of UBCD4WIN and SARDU. All are great, but I have always been an advocate of SARDU. Recently it was suggested that I go back and take a look at Easy2Boot in comparison.
This tutorial will walk an individual through the process of installing the necessary services and then configuring a Windows Server 2012 system as an iSCSI target. To install the necessary roles, go to Server Manager, and select Add Roles and Featu…
This Micro Tutorial will teach you how to reformat your flash drive. Sometimes your flash drive may have issues carrying files so this will completely restore it to manufacturing settings. Make sure to backup all files before reformatting. This w…
Suggested Courses

649 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question