Dell EqualLogic iSCSI storage is designed to easily scale as the need for additional capacity and performance grows. This chat will focus on scalability of Dell EqualLogic iSCSI stoage, how it is accomplished, and why it works so well. Leading the chat will be iSCSI experts from Dell and Dell EqualLogic.

Chat Transcript

	DELL-ToddM	Welcome mgroft
	DELL-ScottH	hello !
	DELL-ToddM	We are waiting for others to join for today's iscsi chat
	DELL-ToddM	We usually have late arrivers and for the first 5 or 10 minutes
	DELL-ToddM	Today's topic is Scaling Equallogic iscsi storage - although we can stray into other iscsi topics if needed
	DELL-ToddM	Or other topics entirely if we run out of iscsi stuff to talk about
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	DELL-ToddM	mgroft - Do you have anything that you want to talk about today?
	DELL-ScottH	I can talk about Flexaddress and totally take us off topic :-)
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	DELL-ToddM	Hey slbrown - How goes it?
	DELL-ScottH	great you scared him away !
	slbrown	it goes well.
	DELL-ToddM	I guess that I scared mgroft!
	DELL-ScottH	you should get a medal for most consistent attendance !
	DELL-ScottH	what's your id on the site ?
	DELL-ToddM	Oh well - just trying to be friendly
	DELL-ToddM	slbrown - Are you a Dell employee?
	DELL-ScottH	no slbrown on the site .. .ohh well no medal for you !
	slbrown	yes
	DELL-ToddM	What group are you in / where are you located?
	DELL-ToddM	I am in Rr5
	slbrown	so am i
	DELL-ToddM	What floor?
	slbrown	1st
		DELL-TravisV joined.
		Dell-Marc joined.
	DELL-ToddM	Hey - It's the iscsi experts!
	DELL-TravisV	Hello
	Dell-Marc	what me worry?
	DELL-ToddM	How it going?
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	Dell-Marc	good, and you?
	DELL-ToddM	Welcome f5team
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	DELL-ToddM	Things are good - I enjoyed your coverage of the Diane Greene thing
	DELL-ToddM	Welcome Jeff
	Dell-Marc	That was the event of the month, right there.
	DELL-TravisV	That was a beautful picture, Marc.
	Dell-Marc	I can guess which one you are referring.
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	f5team	Thanks, I can't find the sound button though :) J/k
	DELL-TravisV	Yup
	DELL-ToddM	I did my own post as well on the Vmware Ceo change as well - http://www.delltechcenter.com/page/07-10-2008+guaranteed+better+vmworld+keynote+comments
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	DELL-ToddM	Opps - forgot to tell Travis about the clicking on links thing
	DELL-ScottH	hey Darin, how goes it ?
	DELL-ScottH	got one !
	DELL-ToddM	You should right click on links to avoid leaving the chat
	Dell-Marc	I saw it Todd, I thought it was funny - because it was true
	f5team	Good thanks! Looking 4 sum eye scuzzie info
		DELL-TravisV joined.
	DELL-ScottH	lol
	DELL-ScottH	looks like you need the 101 session !
	f5team	yes, I'm way behind, Master Yoda
	DELL-ToddM	At this point I believe that everybody on the chat is Dell - so we are kind of waiting for customers to join
	DELL-ScottH	that would be Marc, I am only at Star Wars episode iii luke ability
	Dell-Marc	Yeah, well I always like it when Travis is around!
	DELL-ScottH	yeah you guys always have "engaging" conversations
	Dell-Marc	no no no, he can correct my wayward wanderings!
	DELL-ToddM	We have a few more Equallogic shelves on order as of last week
	DELL-TravisV	Huh. I'm still recovering from looking at Marc's pictures...
	Dell-Marc	Good!
	DELL-ToddM	Looking forward to doing some Hyper-v Vm testing with Equallogic as the storage
	DELL-TravisV	: ::smoke
	DELL-TravisV	Good!
	DELL-TravisV	Hyper-v
	DELL-ToddM	As a followup to the chat from a couple of weeks ago - I posted a page this morning on Md3000i performance monitoring
	Dell-Marc	T-man, where did you get "smoking dude"? He's not in my pallette.
	DELL-ToddM	It turns out that it is possible to use the command line - smcli.exe - to gather array level perf stats
	DELL-ToddM	Here is a blog entry with a link to the page - http://www.delltechcenter.com/page/07-15-2008+array+level+md3000i+performance+monitoring+comments
	DELL-TravisV	: smoke
	DELL-ScottH	quick, customers needed !
	DELL-TravisV	Okay.
	DELL-TravisV	What's the rule? 10 minutes?
	DELL-TravisV	20 minutes?
	DELL-ToddM	Marc - What's the latest in equallogic land?
	Dell-Marc	We've got some very cool things coming up - that we can't discuss here, other than that, we are rolling along very nicely
	Dell-Marc	As more people see what the product can do, we have growing success.
	DELL-ToddM	I really like the Equallogic arrays that we have - and it was easy to add the second one to the first
	DELL-ToddM	But that is all that we have currently
	DELL-ToddM	Until the three additional shelves show up in about a week
	Dell-Marc	So that's a great cue,
	Dell-Marc	What are you using your arrays for now?
	DELL-ToddM	I'm using them for Vms - some Esx and some Hyper-v
	DELL-ToddM	The Vms are running Sql Server and Lamp stack (dell Dvd Store workloads)
	Dell-Marc	One of the things you ought to try when you get the new arrays is to add a new array to the group and then remove one of the exisitng ones.
	Dell-Marc	That shows how you can re-purpose older equipment
	DELL-ToddM	Currently one of our shelves has 7200 Rpm disks and the other has 15K Rpm disks
	DELL-ToddM	All of the new shelves will have 15K disks
	Dell-Marc	Yeah, so you could put in a new 15K array. and then evacuate the 7200 array and remove it from the group. It gives you a great perspective on how scalability works
	Dell-Marc	You can scale capacity or performance or both at the same time
	DELL-ToddM	And when I evacuate the older slower shelf - it will migrate the data to the new shelf?
	Dell-Marc	Yes, it actually spreads the data across the other arrays in the group. It restructures all the data over the remaining arrays in the group
	DELL-ToddM	Automagically? Are there any options that you have to specify?
	Dell-Marc	You have to add usable capacity to an exisitng volume first
	Dell-Marc	but then when you evacuate, the arrays work together to figure out what data goes where
	DELL-ToddM	Would it make sense to record a demo of this when I do it? Or does something already exist?
	Dell-Marc	There is no copy command, the system knows what data is most heavily accessed and spreads it out over the resources that are available
	DELL-ToddM	We could post on delltechcenter.com wih our other great demos - http://www.delltechcenter.com/page/demonstrations
	Dell-Marc	Its a great idea to record a demo - I don't think one exists
	Dell-Marc	you need to do it in time lapse though, because it takes several hours to do
	DELL-ToddM	That's cool - I will just leave the stuff that you actually click on in real time, and the rest will be time lapse
	Dell-Marc	It uses the systems algorithms for load balancing - which are designed to not over-react to sudden, temporary workloads
	DELL-ToddM	Scott is the demo recording master - so I may have to get his assitance
	Dell-Marc	One of the keys to load balancing is to take plenty of time to prevent thrashing
	DELL-ToddM	It will be interesting to see how it reacts to my testing workloads then - becuase they might seem like sudden temp type of workload
	Dell-Marc	Its a cool opportunity for channel partners to help their customers too
	DELL-ToddM	Is there a rule of thumb for how long you need to run a test?
	Dell-Marc	Not that I know of
	Dell-Marc	The whole idea of upgrading on the fly is such a foreign concept, most people don't believe it can be done that way, but when they see it, they are amazed
	Dell-Marc	The key to it is the distributed volume manager in the Ps5000 arrays
	DELL-ToddM	The software on the arrays is clearly the advantage of the Ps5000 arrays
	Dell-Marc	Todd, back to your question about "how long to run a test" There is some dependence on the amount of data stored in the system, but I don't have any "rules of thumb" for you.
	Dell-Marc	Another thing that really makes a difference is the way the Ps5000s use the iscsi redirect function
	DELL-ToddM	I'll figure it out, I'll be sure to run some warm-up tests that are long enough to ensure that the arrays have done what they want to do in terms of optimizing things
	Dell-Marc	Sounds good
	DELL-ToddM	In terms of scaling out with Equallogic arrays - Is there a limit or best practice for max number of shelves?
	Dell-Marc	That's a really good question. Some of our customers top out at 4 -5 arrays in a group. It can be higher, but I think it makes sense to limit the size of the groups.
	Dell-Marc	There aren't any defined best practices for this yet
	Dell-Marc	Btw, its a small thing, but we try not to call them shelves because they are complete systems, not just drives and connectors. Every system is complete with all the stuff, mirrored cache with battery backup, full software (including all future Sw, etc)
	DELL-ToddM	Sorry for using the wrong terms - Is it better to say Array?
	Dell-Marc	Its Ok, , but array is a better word.
	Dell-Marc	When people think of shelves, I think they think of a bunch of disks that connect to a controller somewhere. There are implications about that that don't fit the Equallogic design model
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	DELL-ToddM	I agree that it makes more sense to call them arrays
	Dell-Marc	If you can add lots of disks without adding controllers, you tend to boost capacity but hurt performance
	DELL-ToddM	Welcome Razec
	Dell-Marc	With a Ps5000 array, you add controllers, ports and cache along with disks, so that performance scales with capacity
	DELL-ToddM	And the beauty of the Equallogic software is able to make all the arrays work together easily
	Dell-Marc	Yep, that's a function of the distributed volume manager and higher level virtualization layers
	DELL-ToddM	Razec - We are just having a discussion about Equallogic and what it means to scale up
	DELL-ToddM	Feel free to jump in with any questions or comments
	RAzec	thanks,
	DELL-ToddM	Marc - It looks like I will be well positioned with the four Equallogic shelves
	DELL-ToddM	I mean arrays!
	DELL-ToddM	Old habits are hard to break sometime
	DELL-ToddM	As long as I don't refer to the management utility as Navi - I think we will be Ok....
	Dell-Marc	You'll be fine (I think) . We might have to shine the Mib light in your eyes. You'll be able to do an number of experiments in scaling - including using the systems's native thin provisioning
	DELL-ToddM	What does thin provisioning mean?
	Dell-Marc	Thin provisioning is a way to say you have more storage than you actually have
	Dell-Marc	The idea is to buy small knowing you'll need more later
	Dell-Marc	Its like credit - for storage capacity
	DELL-ToddM	So the hosts think that they have more storage than they do?
	Dell-Marc	exactly
	Dell-Marc	A lot of the times, admins don't have any idea how much capacity growth there will be and when, but they know its going to happen
	Dell-Marc	Thin provisioning allows them to spend less now and provision more later when they need it
	RAzec	and how it works , it is based based on predefined rules/thresholds?
	Dell-Marc	That way, they don't waste a bunch of valuable storage space waiting for an application (or system) to grow
	Dell-Marc	Its based on a couple things:
	Dell-Marc	The initial provision is based on a percentage of space you actually want to use
	Dell-Marc	Then there are thresholds, warnings and brakes that are applied as you reach capacity levels
	Dell-Marc	An admin has to add storage when needed, there is not an automated way to add more (that I know of)
	RAzec	right, probably you don't want to give to the system that level of automation..
	Dell-Marc	One thing that's cool about Equallogic's algorithm's is that if you want, you can take a volume that has been thin provisioned and turn it into a normal volume
	RAzec	on the fly?
	Dell-Marc	So if you start thin, then at some point add more - and say things stablilize or the application is not beiong used as much, you can convert it to a normal volume and remove the risk of over-extending "credit"
	Dell-Marc	Yes, on the fly
	Dell-Marc	Obviously there has to be sufficient space available.
	Dell-Marc	Another thing that you'll find interesting is the interlock between snapshot capacity and thinly provisioned volumes. Allocated capacity for snapshots are automatically adjusted as additional capacity is added to a thinly provisioned volume
	DELL-ToddM	Very cool - Does it include the check for the needed space for snapshots, when you add capacity to the thin provisioned volume?
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	Dell-Marc	Hey, todd is it ::beer time for you yet?
	DELL-ToddM	It is a bit past time for me!
	DELL-ScottH	it sure is when Stuart joins, then we know it;s beer time !
	Stuart	Hehehe
	DELL-ScottH	::beer
	DELL-ScottH	doh, that was loud !
	DELL-ToddM	This was the last of the three week series on iscsi chats - next week we are starting a series of Hyper-v management chat
	Stuart	7am over there.... so about 10hours to go for me... before /beer
	Dell-Marc	Cool
	Dell-Marc	I don't mean cool that you have to wait so long.....
	DELL-ScottH	We also have a special chat on tuesday for Flexaddress that is geared for the european timezones
	DELL-ScottH	9am our time Gmt-5
	RAzec	are you plan to cover vmware any time soon..
	DELL-ToddM	Yes - Techcenter Chats go global next Tues!
	DELL-ScottH	vmware mgmt ? or vmware in general ?
	RAzec	I;m intereseted on Esx/baldes...
	DELL-ToddM	We have done a number of Vmware related chats in the past and we are always looking for new topics
	RAzec	ok , I'll take a look..
	DELL-ToddM	Esx Blades - We are working on a Blades Extravangaza topic to follow the Hyper-v stuff
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	RAzec	ah nice..
	DELL-ToddM	So we will definately have a chat in that time frame that will cover you
	DELL-ScottH	I'd say do it, yes Blades topic starts aug 4th ... but don't wait until then, ask questions on the techcenter site anytime
	DELL-ToddM	In the mean time - you can submit questions on any Techcenter page - at the bottom in the comments area
	RAzec	thanks, I'm newbie.. so...
	DELL-ScottH	yes ! noobs rule !
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	DELL-ScottH	welcome to the site
	Dell-Marc	Todd, Btw, I just saw the Q on thin provisioning and snaps: The system add add'l snap space when space is added to a thinly provisioned volume
	DELL-ToddM	I would like to give a big thanks to Marc and Travis for helping out with the iscsi topics!
	RAzec	thanks
	Dell-Marc	Thanks for having us (well me anyway)
	DELL-ScottH	thanks for the good times and beers
	Dell-Marc	Travis, ::punk where are you?
	DELL-ToddM	I'm a recoverring Fibre Channel guy and they still talk to me :-)
	Stuart	Yeah guys, thanks! it was a great session!!!..... I only wish i had been here... :)
	Dell-Marc	Yes, you and your old world lexicon
	Dell-Marc	that was for todd
	DELL-ScottH	gutenberg would be proud
	DELL-ToddM	Ah the ole world
	Dell-Marc	go go gutenberg
	DELL-ScottH	thank ye for having us
	Dell-Marc	If only he had beer icons back in the day
	DELL-ScottH	he was so close to inventing the smiley
	DELL-ToddM	I've gotta drop off - But thanks to all for attending. (gotta go create some Hyper-v Vms)
	DELL-ScottH	bring out the farm animals !
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	DELL-ScottH	thanks !
	RAzec	:) testing, see ya..
	Dell-Marc	Thanks everybody
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	Stuart	Seeya guys :)
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