How many Exchange servers do I need? 2

[irbk]

I'm preping for the migration to Exchage 2007 from Exchange 2003. I was reading an online article called Installing Exchange 2007 from msexchange.org (here is the link

http://www.msexchange.org/tutorials/Installing-Exchange-2007-Part2.html)

and I'm startled by one of the statements. I'm not sure if I'm missunderstanding what the author is saying or what. Hope you can help me clarify this. In the article the author says

If you are running a multi-site AD environment you need to install a Hub Transport and Mailbox server in each AD Site.

Now, I have 9 different sites in AD Sites and Services. Some small 2 people offices that don't even have a server all the way up to our corporate HQ. Even though we have 9 sites, we only have about 200 users. Currently our single exchange server, located at our corporate HQ, hosts all of our mailboxes and exchange services. The way I'm reading this artilce, if I migrate to Exchange 2007 am I going to need 8 more exchange servers?!? Or can I continue to run in a single server environment as I have in the past?

Thanks in advance.

 

[cajuntank]

You can continue to run a single server. I believe he might have been eluding to having multiple Active Directory Domains, although off the top of my head, I don't see why that would be an issue either especially with only 200 users. I can see in a rather large environment having hub and mailbox server(s) at each site, but not for 200 poeple.

I'm sure someone can offer a more technical explanation on the "multi-site AD environment" terminology he used, but I and many others are just like you with one domain, multiple sites, and one multi-role server.

 

[theravager]

Basically you need a server with the hub role in any AD site that has a mailbox server.

Clients can connect from anywhere.

 

[58sniper]

Single server is fine, technically. You need to think about availability and resiliency to determine if only one server is adequate.

Pat Richard MVP
Plan for performance, and capacity takes care of itself. Plan for capacity, and suffer poor performance.

http://www.ucblogs.net/blogs/exchange/

 

[irbk]

You need to think about availability and resiliency to determine if only one server is adequate.

Yeah, I can tell you don't work for my company. I believe our corporate policy is to not pay for any redundancy or disaster recovery and then when something goes awry (that having some redundancy or disaster recovery plan would have covered) management should complain about how long it takes to get things back on-line.... As a matter of fact, our disaster recovery plan matches Dilbert's to the letter!!!

http://content.volomedia.com/media/ringtales/content/d042.m4v

 

[irbk]

Thanks for all your help folks! It looks like I can continue to have a single server. I appreshate the help!

 

[Zelandakh]

Single server but get disk redundancy at least.

 

[irbk]

Oh, yeah, that's a given. I'll probally use the... uh, what's it called.... I think it's either called Raid 10 or Raid 1+0. 4 disks, supposed to have the redundancy of a RAID 5 with out the write latency.

 

[Zelandakh]

Yes, that will be good. If you have good links between the sites, 1 server will work but a GC in any site over about 20 people (ish).

 

[58sniper]

200 users on a single RAID 1+0 array? How big are the mailboxes? You have another array for the transaction logs, and an array for the OS, right?

Pat Richard MVP
Plan for performance, and capacity takes care of itself. Plan for capacity, and suffer poor performance.

http://www.ucblogs.net/blogs/exchange/

 

[Zelandakh]

You could get a mirror for the OS and at a push a mirror for the TLs.

Depends on usage stats really.

 

[irbk]

Haven't decided if the OS would be on the same RAID 1+0 or on a simple Mirrored drive. Ideally, OS on a 2 disk Mirror, Exchange DB on the RAID 1+0, and transaction logs on a 2nd set of mirrored disks, or at the very least on a single disk. I don't know for sure what the budget will allow me though.

It's not actually 200 users, were only about 150. We would be upping the mailbox size from 500mb to 1gb. 90% of our users keep a pretty clean mailbox, the other 10% run it up to the limit. My assumption is 150 users with a 1gb mailbox will make my priv.mdb ~ 75 to 100 gig.

 

[baddos]

My assumption is 150 users with a 1gb mailbox will make my priv.mdb ~ 75 to 100 gig.

EEK! I haven't followed up on 2007 but is it cool for a single mailbox store to be that large?

Also 1gb for a mailbox? You are the coolest IT admin ever.

 

[58sniper]

Well, 150 @ 1GB each means you end up with more data than is recommended in a single database. Making some assumptions:

Deleted item retention: 14 days
No High Availability
150 users @ 1GB
10% growth in mailbox count
all users in cached mode
no Blackberry units
no journal based archiving

You'd need 2 storage group LUNs of ~139GB each each with a single database in each holding ~83 mailboxes
You need 2 transaction log LUNs of 12GB each
You need a Recovery Storage Group LUN of 145GB

Now you'd have to figure out what RAID levels and how many spindles in each you'll need in order to meet your needs.

Pat Richard MVP
Plan for performance, and capacity takes care of itself. Plan for capacity, and suffer poor performance.

http://www.ucblogs.net/blogs/exchange/

 

[Zelandakh]

1GB mailbox? Very small...

Transaction logs...single spindle...DON'T. You have to have resilience there.

 

[irbk]

Also 1gb for a mailbox? You are the coolest IT admin ever.

Not really. IMHO 1 Gig is kind of the standard.

150 @ 1GB each means you end up with more data than is recommended in a single database.

Really? Where did you get that information from? Last time I read through the information, I didn't see any maximum numbers.

http://technet.microsoft.com/en-us/library/bb738147(EXCHG.80).aspx

seems to have no problem with creating a 144 GB LUN. Please, let me know where you've seen the recomended LUN size so that I can plan accordingly. Also, I understand that I need to plan for a capacity of 220 GB (200 users at 1 GB + 20% overhead). I'll be more then happy to take additional information into consideration when I'm planning the deployment.

 

[58sniper]

Not really. IMHO 1 Gig is kind of the standard.

Not even close. Many surveys show it's still in the 100MB range.


The recommended mailbox store size is 100GB if there is no continuous replication and 200GB if there IS continuous replication (and I believe your MS link discusses it being a CCR environment). Straight from the product group. This is for performance, reliability, and backup/recovery purposes.

Pat Richard MVP
Plan for performance, and capacity takes care of itself. Plan for capacity, and suffer poor performance.

http://www.ucblogs.net/blogs/exchange/

 

[irbk]

Many surveys show it's still in the 100MB range.

I'd love to see these surveys. Something to show management when they balk at having "only" 1 GB.

 

[irbk]

The recommended mailbox store size is 100GB if there is no continuous replication and 200GB if there IS continuous replication

Can you provide me with a link on that?

 

[irbk]

Now you'd have to figure out what RAID levels and how many spindles in each you'll need in order to meet your needs

Ok, here is what is going to sound like a dumb question, define for me what the difference between a disk and a spindle is. I always thought that the spindle is what the platters of the hard disk spin on, but I'm reading this thing on exchange 2007, and it says "Invest in high performance disks and spindles" which to me means they need to be 2 different things, right?