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.

 

[Zelandakh]

A spindle is part of the disk drive. Increasing spindle count increases performance.
A disk is part of the disk drive. Increasing disk I/O increases performance.

Yes, they are part and parcel of the same thing but some people would be better off with 10 IDE disks where others would benefit from 2 fibre disks (deliberately exaggerated).

Spindles to me are number of disks and their spin speeds.
Disks to me are types like IDE, SATA, SCSI etc.

 

[irbk]

So is it really possible to purchase a high performance disk that doesn't have a high performance spindle or vice versa?

 

[Zelandakh]

7,200rpm IDE is fast spindle for IDE but IDE is slow transfer.
7,200rpm SCSI if you can still get them is relatively slow spindle speed for a faster transfer.

Repeat as you will. You can't really get slow spindle and fast disk but all things are relative.

I like SAS as it is a fast disk but it isn't good for IO intensive operations like Exchange unless you really throw spindles at the problem but then again, 10 SAS disks will be a lot cheaper than 5 disks off a NetApp SAN.

 

[58sniper]

I like SAS as well. 15,000 RPM for the logs, 10,000 RPM for the databases is typically what I use (although I do have some installs with 15k all around).

As for the 100MB mailbox limits, I know of at least two of the major automakers who limit EVERYONE to 35MB. THIRTY FIVE MEGS!

Even my wife's law firm, which deals with intellectual property law, and sends/receives big attachments, uses 35MB. I feel sorry for her.

I've had the same mailbox for ~15 years. I get over 1000 legitimate messages a day, and my mailbox is south of 500MB.

Giving people large mailboxes just because you can isn't the answer, as it doesn't get the user to be responsible for their contents. Now, Nick will say that large mailboxes aren't a big deal. They aren't - when they're needed.

My favorite analogy is a woman's purse (and this isn't meant to sound sexist). If you give a woman a small purse, she crams the needed items into it. It's full to the top. Now - give her a big purse, and she'll cram more stuff into it - to the top. Why? Because SHE CAN. Life was fine when she had the small purse. People weren't dying, and the world didn't collapse.

The same applies to users. Give them more space, and they'll cram more stuff into their mailboxes - much of it non-job related. IMHO.

Should the business bear the cost of letting users keep emails with 10MB of pictures of their kids playing baseball, or the endless "where do you want to go for lunch?" emails? No. Get the users to keep only relevant business related data in there, and mailbox sizes drop considerably. And then, so do backup and restore times. And AV scanning times. And nightly management times. And then performance increases.

This doesn't mean they can't receive those 10MB of pictures or the lunch emails. Just that they need to get rid of the black hole mentality when it comes to keeping email.

Just my .02.

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]

Ahh. ok. Thanks.

Now one last question (ok, it probally won't be my last question).
I'm looking at the exchagne calculator, and it recomends that I have 3 databases on 3 different LUNS.
My assumptions (that could be totally wrong and please correct me if I am)
1. A simple way to see a LUN is like a drive letter, such as "E:\"
2. A physical drive set such as a raid 5 or raid 10 can have several LUNs, like E:\, F:\ and G:\ (all on the same RAID)

So, here is my question. If LUNs are all located on the same RAID, just different drive letters, how does this improve the performance of my Exchange server? For example, lets say my 3 mail databases for exchange are located on E:\, F:\ and G:\. E:\, F:\ and G:\ are all located on the same physical RAID. E:\ can't write or read from the disk while F:\ or G:\ is, so how does this get better performance then just having 1 large mail database? Isn't X amount of "mail in/mail out" going to be the same amount of I/O's regardless of if your DB is in 1, 2, 3, or more databases?

 

[58sniper]

XMSRE is the best person to answer this, but your drive letters don't necessarily go on the same array. You need to determine what the array is capable of handling from an IOPS perspective to determine how many SGs you can pile onto it.

You could have one array for each SG if needed.

You also need to consider how long to restore a specific database will take as well.

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]

Giving people large mailboxes just because you can isn't the answer...

I totally agree. Most of my users can keep a clean mailbox. The rest can't. I believe the last time I did the math, 20% of our users were using 80% of the space. I know within days (if not hours) of raising the limits, the few that can't control their mailbox at 500mb will be right up to 1 GB. I can only do what management tells me too, and urge against the bad ideas, but I'm just the IT guy so what do I know. Part of the problem is that our project managers (most of the ones that can't keep a clean mailbox because they are far too busy) tell upper management that 500 MB is too small and if they can't get there job done then they will just start using Yahoo/G-mail/etc. Upper management doesn't want that so they then yell at us. God forbid that the PM would delete the 10MB e-mail of there kid playing baseball or any other message for that fact. After all, I might need to know that Kelly wanted to go for Mexican food today 6 months from now. Unfortunatly, a precedence has been set, and if a users mailbox gets full they just start offloading it to a PST and there isn't anything we can do about it becuase IT management has no power and upper management won't support and IT proclamation that we won't support PST files anymore and your mailbox size is your mailbox size so learn how to keep it clean... ARGUHHHHHH..........

*Sigh* Sorry, you hit a rather sore spot with that toppic. I look at it as an excuse to spend some good $$ on a server. If management wants everyone to have a 1 GB mailbox, fine, it's gonna cost them!

Thanks everyone for your posts. I don't know what it is about Exchange 2007 but I'm just having a hard time trying to wrap my head around all the recomendations.

 

[irbk]

your drive letters don't necessarily go on the same array

Sorry, I guess I should have specified that I do realize they don't HAVE to go on the same array, but they can, and in the case of the exchange calculator, they would.

 

[58sniper]

I totally agree. Most of my users can keep a clean mailbox. The rest can't. I believe the last time I did the math, 20% of our users were using 80% of the space. I know within days (if not hours) of raising the limits, the few that can't control their mailbox at 500mb will be right up to 1 GB. I can only do what management tells me too, and urge against the bad ideas, but I'm just the IT guy so what do I know. Part of the problem is that our project managers (most of the ones that can't keep a clean mailbox because they are far too busy) tell upper management that 500 MB is too small and if they can't get there job done then they will just start using Yahoo/G-mail/etc. Upper management doesn't want that so they then yell at us. God forbid that the PM would delete the 10MB e-mail of there kid playing baseball or any other message for that fact. After all, I might need to know that Kelly wanted to go for Mexican food today 6 months from now. Unfortunatly, a precedence has been set, and if a users mailbox gets full they just start offloading it to a PST and there isn't anything we can do about it becuase IT management has no power and upper management won't support and IT proclamation that we won't support PST files anymore and your mailbox size is your mailbox size so learn how to keep it clean... ARGUHHHHHH..........

*Sigh* Sorry, you hit a rather sore spot with that toppic. I look at it as an excuse to spend some good $$ on a server. If management wants everyone to have a 1 GB mailbox, fine, it's gonna cost them!

Thanks everyone for your posts. I don't know what it is about Exchange 2007 but I'm just having a hard time trying to wrap my head around all the recomendations.

My answer to management is rarely "No". It's usually "Yes, but this is how much it will cost...."

.pst files aren't the answer - ever. Management needs to understand the legal issues they bring up, not to mention the administrative headaches.

"Larger mailboxes? Sure, but we need a new SAN, and a larger tape drive, which will costs us $75,000. Getting users to clean up their mailboxes is free, and makes them more productive. Not only do we not have to spend more, we could potentially make more."

That gets them thinking.

Sorry, I guess I should have specified that I do realize they don't HAVE to go on the same array, but they can, and in the case of the exchange calculator, they would.

Yes, but with a single DB in each SG, backup and restore is easier. You can manage the users at the SG store level by putting users with the same limits in one DB.

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]

Ah, ok. From the aspect of backup that does make more since. Don't have to reastore an entire 150 GB database to recover 1 50k e-mail. I like that idea. Thanks 58Sniper! That makes SO much more since now! See, this is why I pay you the big stars!

 

[Zelandakh]

You can put the volumes into the same LUNs but you won't get a better performance - DR will be easier though.

One vol, one LUN is best.

 

[baddos]

Unfortunatly, a precedence has been set, and if a users mailbox gets full they just start offloading it to a PST and there isn't anything we can do about it becuase IT management has no power and upper management won't support and IT proclamation that we won't support PST files anymore and your mailbox size is your mailbox size so learn how to keep it clean... ARGUHHHHHH..........

You can do something... You can disable Outlook's ability to create .PST files from group policy.

.PST files are bad! They are insecure, probably not backed up, and portable so an ex employee can walk off with your company email, contacts, etc.

 

[Zelandakh]

PST files on a local machine are not backed up and prone to corruption.
PST files on a network waste space, are even more prone to corruption and are just bad especially for performance.

Just get mgmt to increase the limits. 6GB is good.

 

[irbk]

disable Outlook's ability to create .PST files from group policy

Except they already do use .PST files and if all of a sudden they can't then I'll be getting phone calls asking "Why can't I create a PST". I can't exctally reply with "We disabled that" because the users will whine to their managers who will whine to the higher ups who will yell at my manager who will then yell at me. I've already thought the situation through. The best that we can come up with is that when we migrate to 2007 PST files "won't be supported in 2007" thus the reason why we upped the mailbox limit to 1 GB.

 

[baddos]

Yeah if you just change something without telling management of course there will be some people getting emotional. However, if you brought the issue to management and laid out a resonable plan I'm sure you would have open ears.

 

[irbk]

We did bring a plan to management. Even laid out all the pros and cons in real small words so they could understand it. Didn't make any difference.

 

[58sniper]

We did bring a plan to management. Even laid out all the pros and cons in real small words so they could understand it. Didn't make any difference.

I hate to say this, but wait till it fails. Someone blows out a local .pst file. "Sorry, we told you it was a bad idea".

If you have .pst files on network shares, I'd fight really hard to get that changed, even shoving a copy of the KB article in their face.

As for the .pst GPO, you can restrict their ability to create NEW .pst files while they still have access to current ones.

Oh - and thanks for the star!

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]

Yep, we have to do a LOT of that around here. We basically do exctally that. The user wants it set up and we set it up and tell them that it's not backed up and if the file gets corrupt then they are out of luck.

You are welcome for the star, you earned it!