Dave Graham’s Weblog

Obviously, I do actively read and/or manage my blog. To that end, one of the nifty little features of WordPress (and undoubtedly other blogging sites) is the ability to “see” what search terms people are using to land on your blog posts. One of the most fascinating searches had to do with the phrase “Centera vs. Symmetrix.” There are other good search metrics that I’ve seen but I thought I’d delve into this for a second.

As you’ve undoubtably read before, I did a quick drive-by of the Nextra and in it, promoted the concept that Nextra could become a significant competitor to EMC’s Centera. While this may be slighting the Nextra and Centera somewhat, it does point to the fundamentals of near-line archive being a significant battleground in the coming years. So, to flip this on its head a little, let’s look at the Centera vs. the Symmetrix as wholistic entities dedicated to storing YOUR information.The Symmetrix is a purpose-built, multi-tiered storage system with infinite expandability (well, finite, really, but hyperbole works well, right? ) , connectivity, and AT LEAST 3 tiers of discrete information storage (Tier 0 [SSDs], Tier 1 [fibre], Tier 2-5 [SATA]). The Symmetrix will connect to anything from mainframes to lowly Windows 2003 Servers. It has completely redundant pathways to your data and features a high speed internal bus interconnecting the blades.The Centera is a system based on the RAIN (Redundant Array of Independent Nodes) principle. By itself, the Centera is realistically nothing more than a purpose-built 1U server with specialized policy-based software sitting on top of a very stable Linux OS. (The Centera guys will more than likely want to harm me for distilling it down that far). However, moving the Centera “nodes” from standalone to clusters (aka 4-node “base” units) really changes things and highlights the power of the OS and hardware. Connectivity is limited to IP only (GigE, please!) and the nodes communicate with each other over IP (dedicated private LAN) as well. Not quite as flexible as to the front end connectivity and definitely not the champion of speed by any stretch of the imagination (thanks to SATA drives), but very servicable when using the API to communicate directly. Remember, the Centera is geared toward archive, not Tier 0-3 application sets (though, it appears to function quite well at the Tier 2-5 levels depending on the application).

Hopefully, you’re seeing a pattern here that will answer this particular tag search. If not, here’s the last distillation for you:
Symmetrix: multi-protocol, multi-Tier, high speed storage system
Centera: single protocol, single-Tier, archive storage systemCapiche?

SAS vs. Fibre Challenge

Again, as I’ve pontificated before, I challenge anyone to point out SAS’s shortcomings as it pertains to reliability and performance vs. fibre drives. I see the market turning to SAS as the replacement for Fibre drives and, well, we’ll see where that goes. To that end, I’ve got an interesting challenge for you readers:

The Challenge:
a.) I need someone with a CX3-10 and someone with an AX4-5 base array, with fibre drives and SAS drives respectively.
b.) I need the fibre and SAS drives in a RAID5 4+1 config with a single LUN bound across it (no contention of spindles
c.) I need you to run either the latest version of IOMeter or OpenSourceMark (the FileCopy Utility) against that LUN and report back the information.
d.) I’ll compile the table of data results and, if I receive valid results from multiple people, I’ll send you an EMC t-shirt for your time (to the first responders).Sound like a deal? GREAT!(I’d do it myself but I have no budget for these things…)

Checking out now…

Dave