Server specification

how large is a growing user base ?
and expect to replace server at around 5 year time..

idealy if its a very small net work you might want to repace sooner. but 5 years should be what you are aiming at..

looking further ahead than that and you would have to spend silly money. not looking that far ahead and you will need to buy new server very soon..

so how many users are u thinking of supportying. first to start of with. and how quick do you expect to grow?

We have been purchased by a bigger company and we will be expanding to around 200 users in the next 12 to 24 months.  New users are joing every other week although curently we only have around thirty IT users.

Thus I need to purchase an IT solution which can accomodate this rate of growth.

   

I think DevilWAH said it all there, not much to add really. Don't think you have to be too worried about performance, 200 users will be handled just fine by most servers. But spend a few extra bucks on the exchange server, and don't be cheap when it comes to RAM on either of them.

Dell 2950's are very solid server, but I prefer HP Proliant DL series myself.

yep makes are a very much personal thing ;) you can argue all dave over which ones better and i am sure some people will tell you horror stories about any make. but to be fair we have few problems with our dells.  and prices arnt bad..

also i would get at least two raid cards in the exchange server. so each array can run on its own card.. again not required but allows for future expansion.

Thanks for that.  

I am new to setting up raid configuations.  Please be patient.  What configuration would you suggest I use for Exchange.

e.g. 2 * mirrored boot drives (C drive).  3 * Raid 5 hot swap drives for Exchange database (D drive).  3 * Raid 5 hot swap drives for Exchange log files (E drive).

actualy i would not suggest raid 5 unless you are suing at least 6 drives (5 for the array and one hot spare)

raid 5 is actauly not as ggood proformance as striped by a long shot. And even two mirrored drives wil out proform a raid 5 array with three drives..

i would suggest using a mirrored striped array.

which is 4 drives. you make two sets of mirror arrays each with t disks.. and then stripe accross them.

or you can do it the otehr way and set up two striped arrays and mirrror them..

this will give you much better proformance and deffently what i would go for for the log's as they should be quite static in size giving you time to expand when you need to.

the data base you should be ok with a raid 5, although if possible use more drives..

and yep jsut a mirror for the OS drive would be fine..

but i agree with the 3 seperate arrays deffently

sorry the mirrored striped sets or striped mirroed arras are know as raid 0+1 / 1+0 or even some times as raid 10 or raid 01.

but if you know what a mirror and strip set are jsut think about stacking them on top of each other. However with this you do lose half your disks..

The real bottle neck in an exchange server is the log file array as this is recording every transaction as it happens on the CPU... so it has to be fast. you want 15k disk with fastest access speed possible. the os can be quite slow. and the data base whould be ok running on raid 5 which offers good all round proformace with less loss of disk space..

How does this sound.

1) Mirror the OS drive.  Raid One.  Use 2 drives.
2) Exchange database.  Raid 0+1.  Use 4 drives.
3) Exchange log file.  Raid 0+1.  Use 4 drives.

10 drives in total.  Three raid controllers.

For 200 users RAID 1 rather than RAId 10 is fine for logs, that would cut it down to 8 disks which can fit in 1 2U server. I can't see much need for multiple RAID controllers, one will do.

There's a Proliant sizer for Exchange 2003 at http://h71019.www7.hp.com/activeanswers/Secure/80663-0-0-0-121.html, you'll need to cerate a free account to download it. Then, if you want Dell, you can simply convert to another server with similar performance specs.

I would agree that raid 1 would do. however i would suggest that it would be better to cut back on the data base proformance than the log files.... seeing as these are normaly more of a bottle neck..

i suggest two raid controlers for another reson as well..

if you have one and the card goes you are a bit stuck...
if you have two. and they are multi channel. you can open the server move a cable accross and reboot and you back up and running ;)

Always think redundence..

Well, your milage may vary but the sizer doesn't start using RAID 10 for logs until there are about 12 data disks

what ? that comment is lost on me...

but any way i think we can both agree the specs i suggest would happily be sufficent for a while yet to come and lots of growth.

we could argue for days as to what is the best specs for a server for this (as is the case with most of IT stuff ;) ). but i would think you should look to spend up to about £4,000 a server.

and make sure you have redundency in every system..

Again i also think you should look at having two Domion controlers..  (for a while we had  a desktop with 2 gig ram and a raid 1 array as a seconday DC, ok it wasnet amazing. but it did mean if the primary one failed at least we would still be able to let users log on and work.. might have been slow but better then taking the whole company out!!)

I have a budget of around £5,000.

Just to confirm then I need three raid configured drives (as follows) and two raid cards will cover this?

1 for Boot drive, 1 for Exchange database, 1 for Exchange log files

well you could get away with one if nessery but yes you do really want 3 raid arrays.

Logs must be seperat from the database/os.. Logs are writen as a singel continous stream of data. so are written most efficently on there own were the write head dosent have to jump around between log files and data base..

you could if you wanted run a raid 5. and split it in to two partitions. one for OS and one for data base if you wished..

I do suggest two raid cards.. but make sure each one can support the number or arrays you need.. some raid cards only support one array. so if you go for three arrays you will need duel channel raid cards..

HP don't do controllers that only support one array and I don't think Dell do either, P400 for example goes up to 32 logical drives, PERC4e/dc supports 40 logical drives.

but they are not the only controlers you can buy on the market! and the PER4e/DC is not the only card Dell do??

there are many cards out there that dont support mulitply arrays. and even some that do will not be very good.

the dell PER 4e/DC has the added benifit of being duel channel so it has two u320 scsi channels. meaning each channel has its own dedicated path in to the system.

Well, I think they ought to go for a controller that supports multiple arrays and logical units then rather try to use multiple controllers. If they can get it to fit on 8 disks then a DL380 G5 or a Poweredge 2950 III will take 8 SFF disks internally in which case they can only have one or two controllers due to the disk backplane wiring unless they expand to external storage. They obviously want HP or Dell since it says that in the tags in the question.

I think the previous comments are good but here is a little low level look at things.  Two controllers is good for redundancy but if you purchase a 4 hour 7x24 contract, you don't need the redundancy.  If you use two controllers, the performance benefit will be minimal.  The arrays would be using different scsi buses which would lead you to expect better performance.  However, typically you don't have more than 2 pci buses on the system board.  That means that both controllers will most likely be operating on the same pci bus and bottlenecking the gains from using two controllers.  To sum it up, two controllers is good but only if you want the added redundancy.  Since price is a factor, I would recommend spending the money on the best warranty rather than the added components.

Also, raid 10 is the closest you can get to a raid 0 performance and have redundancy so I don't want to take away from the previous comments but I don't think you will need that for 200 users.  I think 7 disks would be good.  2 in raid 1 for the OS.  2 in raid 1 for the database.  2 in raid 1 for the log files.  1 hotspare.  Shelf stock is always good too but only as the budget allows, of course.  You may want to think about how many users the new comany adds each year.  You are expanding to 200 for them but are they growing at 30 people a year?  If so, you should plan for the extra 150 users (30/yr x 5 yrs).

I can't really see any benefit of having a redundant RAID controller, if you have to take the lid off to swap the cables you might as well swap the whole board, it only takes about 20 seconds longer than swapping just the cables.

I guess you get twice the cache with 2 controllers but, at least with a Proliant, if you then moved both sets of disks to one controller you can end up not booting at all since one array will be renamed Array B and you can only boot from array A.

I'd start with a single quad core, you can always add another one later and they'll probably be cheaper next year, similarly with RAM and disks, you can always add 300 external disks to a DL380 if you want with external enclosures :)

As far as RAM is concerned which version of Exchange is in use? And 32 bit or 64 bit? Exchange 2003 will only use 3GB RAM max anyway.

i agree with andyalder with 4 gig in the system you can give exchange 3gig and leave 1 gig for the OS.
ITs a little bit of an over kill but it still not to expensive and i think worth it..

and sifuedition a "Two controllers is good for redundancy but if you purchase a 4 hour 7x24 contract, you don't need the redundancy" means you will be of line for up to 4 hours!!! not sure about your company but 4 hours for us is 4 hours to long! + a second raid card will be a lot cheaper than that service contract!

as for warenty i think its actuly cheaper to know how todo your own repais and keep some spares around. I accept it may be different with only a few servers. but i'm afraid i am use to 80 odd servers. for us its better to stock spare parts and jsut replace them our selves. we can have an in house support that does a lot quicker then 4 hours, But i supose that comes for having a lot of experince here. and getting to play with servers all day..

Thanks for all the comments which are very much appreciated.   Can anybody recommend a third server model to go with the Dell PowerEdge 2950 and HP Proliant DL380?  I would like to compare three models based around the specification discussed here.

own build maybe...

its not that hard these days. and in fact if you havent built a server before i would suggest that you give it a go. it wont be much cheaper but it will teach you a lot about the different compnents.

you say you are a bigginer on servers and this would be a great way to learn a bit more.. and belive me once you get a few more servers after this it might be a long time before you get to get your hands dirty again ;)

as for other makes i dont really know. i have only used dell and compaq (now hp i belive we dont use them any more) so i dont want to suggest any others as i cant vouch that they are any good. these two are the two market leaders of microsoft servers. IBM i think still make servers. and there are others but i will leave it to some one else to suggest them..

IBM 3650 would be equivalent, there's an 8 disk SFF model. Don't compare prices on the web, Dell sell primarily through the web and the online prices reflect that, HP and IBM sell through the channel so the web price is higher than you will get from a reseller.

VLA using Dells? Have to get one of our salesmen in there; HP have some special offers for converting Dell houses to HP houses ;)

you know the VLA??? (hangs head in shame!!)

And i dont have any thing to do with purchases!! only in playing with them :)

Not directly; one of our salesmen asked me to meet him for a pre-sales at "the" veterinary labs in in Surrey so I went to your place and he went to Pirbright!

aww cool

i work on the main site.. if it was in the last three or four years you probable walked past my desk if you came in the it unit.. !