Yesterday, In his blog posted entitled “Myth Busting: Storage Guarantees“, Vaughn Stewart from NetApp blogged about the EMC 20% Guarantee and posted a chart of storage efficiency features from EMC and NetApp platforms to illustrate his point. Chuck Hollis from EMC called it “chartsmithing” in comment but didn’t elaborate specifically on the charts deficiencies. Well allow me to take that ball…
As presented, Vaughn’s chart (below) is technically factual (with one exception which I’ll note), but it plays on the human emotion of Good vs Bad (Green vs Red) by attempting to show more Red on EMC products than there should be.
The first and biggest problem is the chart compares EMC Symmetrix and EMC Clariion dedicated-block storage arrays with NetApp FAS, EMC Celerra, and NetApp vSeries which are all Unified storage systems or gateways. Rather than put n/a or leave the field blank for NAS features on the block-only arrays, the chart shows a resounding and red NO, leading the reader to assume that the feature should be there but somehow EMC left it out.
As far as keeping things factual, some of the EMC and NetApp features in this chart are not necessarily shipping today (very soon though, and since it affects both vendors I’ll allow it here). And I must make a correction with respect to EMC Symmetrix and Space Reclamation, which IS available on Symm today.
I’ve taken the liberty of massaging Vaughn’s chart to provide a more balanced view of the feature comparison. I’ve also added EMC Celerra gateway on Symmetrix to the comparison as well as an additional data point which I felt was important to include.
I’ve included some footnotes in the chart to explain some of the results but I’ll explain a little here as well.
1.) I removed the block only EMC configuration devices because the NetApp devices in the comparison are Unified systems.
2.) I removed the SAN data row for Single Instance storage because Single Instance (identical file) data reduction technology is inherently NAS related.
3.) Zero Space Reclamation is a feature available in Symmetrix storage. In Clariion, the Compression feature can provide a similar result since zero pages are compressible.
I left the 3 different data reduction techniques as individually listed even though the goal of all of them is to save disk space. Depending on the data types, each method has strengths and weaknesses.
One question, if a bug in OnTap causes a vSeries to lose access to the disk on a Symmetrix during an online Enginuity upgrade, who do you call? How would you know ahead of time if EMC hasn’t validated vSeries on Symmetrix like EMC does with many other operating systems/hosts/applications in eLab?
The goal if my post here really is to show how the same data can be presented in different ways to give readers a different impression. I won’t get into too much as far as technical differences between the products, like how comparing FAS to Symmetrix is like comparing a box truck to a freight train, or how fronting an N+1 loosely coupled clustered, global cached, high-end storage array with a midrange dual-controller gateway for block data might not be in a customer’s best interest.
What do you think?
Chris
July 24, 2010 at 1:33 pm
If massaging data to positively reinforce your own agenda wasn’t possible and there was a single absolute way to properly interrupt the data then politicians, news agencies, and commercial statistics companies would be out of jobs.
All in all your re-representation of the chart is valid, but really just re-arranges things and cleans things up because you took issue with the way another person represented the information. You’re both correct in your own views of the data and the way you rearranged the chart isn’t necessarily demonstrating anything ground breaking or proving something false which another claimed to be true.
I think your headline is a bit sensationalist since you’re not actually calling anybody out on any lies that they’ve put forward. Instead you’ve just performed some clean-up and rearrangement of the data.
I only take issue with two of your footnotes and they’re pretty minor nits. I’m assuming your 2nd footnote is for the replication category, but your chart is missing the label. Also, you begin with RecoverPoint CRR and end stating just RecoverPoint. NetApp’s SnapMirror does compete/have the same features as a lot of the RecoverPoint pieces, but certain aspects of CRR or Application-level CDP don’t exist in their bag of goods. Both products perform asynchronous, semi-synchronous, and fully synchronous (restrictions apply) replication with data compression (again, restrictions apply), but there are certain RecoverPoint pieces that do go above and beyond in their functionality than what NetApp has to offer with SnapMirror and their SnapManager products as far as I know. Personally I’m a fan of both products for different reasons/applications.
In regards to the V-Series front-ending Symmetrix I think there’s a certain sanity check and common sense that applies. NetApp has their own HCL just like any other vendor and if you upgrade to something that isn’t currently on that HCL and supported then you obviously run the risk of running into issues. If NetApp says that version of code and that hardware is qualified, then they’re your point of contact for support – not EMC – assuming you have a support contract with them. In my opinion (so take it as you will) EMC never has to support a V-Series or any other third-party gateway device in front of any of their boxes if the other organization is going to offer you full support on it.
On a side note, at the end you talk about how front-ending a freight train with a box truck might not be in the end-user’s best interest. One would hope the end-user and the vendor, NetApp or other, have performance metrics to base a configuration on so those performance expectations are met before putting something in production. One could also argue that with the advent of virtualization and databases supporting NAS protocols along with larger Ethernet pipes that the market’s need for freight train SAN storage is becoming less and less important. That’s probably more for another discussion though…
Jonas Irwin
July 29, 2010 at 5:37 pm
Hi Richard-
Nice job. I’d love to see you add a few things to the chart including:
1) Sub LUN auto-tiering (FAST)
2) Ability to failover without losing access or requiring re-warm to extended cache (EFD in our case and PAM in ntap’s).
3) Ability to add ports on the fly with no outage (Ultraflex)
4) Integrated I/O splitting for CDP
5) N+1 Clustering for NAS without breaking other mainstream features like snapshots and replication
6) Dynamic LUN migration – (move a lun to any place RAID type or tier in the array without an outage)
7) Ability to manage the array through a single console (not a single console opened for every controller)
8) Space guarantee offering that doesn’t require 96 pages of caveats with things like reduction of databases and other common files to no more than 10% of the total data set.
9) Ability to extend cache with EFD for both reads and writes (and no, nvram isn’t always the answer when back to back CPs happen)
I could keep going but this is probable enough for now 🙂
Vaughn Stewart
July 30, 2010 at 1:26 pm
Richard,
Thank you for taking the time to share information with the community. there’s nothing like an open dialog.
I believe you have one error in your post. When you claim you can’t compare a unified array to a SAN. This is untrue, just compare the NetApp SAN to a Symmetrix or a Clariion. This allows cusomters to understand the differences in storage savings technologies.
I went into details here:
http://blogs.netapp.com/virtualstorageguy/2010/07/myth-busting-storage-guarantees—part-ii.html
Again, thanks for sharing. If you have any feedback, just ping me. I’m more than happy to advance my knowledge base.