virtualizing Exchange 2003 / 2007 for 4.500 users ?

[pfuhli]

Hi there,

we plan to virtualize the "rest" of our servers we drive physically today.

Besides others there is our Exchange 2003 Cluster hosting around 6.000 Mailboxes of 4.500 users. Is there anyone outside who did a virtualization of an Exchange infrastructure in that size?

Any thoughts or experiences about that?

Regards,

daniel

[sbeaver]

It is all going to come down the number of spindals and speed of the disk. I am looking at doing EXCH 2007 for a total of 20K mailboxes

Steve Beaver

VMTN Forum Moderator

*Virtualization is a journey, not a project.*

[crazex]

Dell did a whole case study on this, and presented it at VMworld 2007. I was actually surprised with their results, as I didn't think Exchange would work well in a VM. Here is the link.

http://www.delltechcenter.com/page/Exchange and VMware?t=anon

-Jon-

[admin]

Hi

Have a llok to this technical paper... Microsoft Exchange Server 2003 Performance on VMware® ESX Server 3 ()

[pfuhli]

Yeah I know these papers but they all calculate max. 2.000 users 😕

[MikeTedescucci]

Questions I would ask if I were designing this environment:

• What does your back-end SAN environment look like? 2Gbps/4Gbps, FC/iSCSI, etc.

• Will this Exchange implimentation have its own dedicated SAN?

• What is your Exchange Server design?

I am of the opinion that most (95%) things will work in virtualization as long as it is designed properly, plus it introduces ease of DR/recovery and maximizes resources.

-Mike

[pfuhli]

Hi Mike,

we plan to build up a new infrastructure for our datacenters. Regarding Exchange the situation today looks like this:

- two physical nodes with Exchange 2003 Cluster

- dedicated SAN LUN RAID5 146GB HDDs 15k FC over 2GBit SAN

- Mailstores summarized size: 400GB

- 6.500 Mailboxes

- 4.500 users

We see performance problems which are mainly caused by massive I/O and less spindles.

They guys who are planning the basic infrastructure for our new environment will provide the following data:

- virtualize Exchange nodes to VI3

- migrating to new storage (we don't know the vendor today) to a LUN RAID5 146GB HDDs 15k FC over 4GBit SAN (that's what we know already)

I'm not quite sure if RAID5 will be enough and if we can handle the traffic of 4.500 users with VMs?

Would you say it is "mandatory" that we upgrade to Exchange 2007 and use RAID 1/0? They guys who are planning suggested to p2v our 2003 nodes to VI3.

[frank_wegner]

The page lists 11 technical papers from various sources which all talk about virtualizing MS Exchange (right column).Especially the EqualLogic Performance Paper: Storage Solution for Exchange 2007 talks about a tested configuration which can support the following:

• 60,000 users

• 0.32 I/O per second per user (MS Exchange 2007 "heavy" profile: 0.40 IOPS per user including 20% headroom)

• 300MB mailbox size

• 24 storage groups, 5 databases each

Maybe there are some valuable ideas for you in there...

Frank

[MikeTedescucci]

Hmmm.... I don't know if I would necessarily p2v your nodes, I think i would rather build clean ones and move the data over. in the long run, I think it would be better for your environment.

About your RAID question... I don't know if I would go with RAID5... Again, this is just an opinion, but if you are running a 4Gb SAN environment I don't know that your spindles are going to be about to pump out that data fast enough...

Is your SAN dedicated to Exchange 2007? How much cache is loaded in the SAN?

That EqualLogic paper is very good, I was talking to our EqualLogic SE (Or should I say, Dell SE :smileyblush:) about it. A very good read.

[EllettIT]

Oddly enough the topic at the users group meeting in my area was on Exchange 2007 in a VMware/SAN environment. The speaker was a rep with VMware who had previously worked with Microsoft's Exchange Team before joining up with VMware. Very informative presentation as I remember however I didn't take any notes I seem to remember that she gave a group of reasons for and against using Exchange on VMware. I'll try to round up some contact info and maybe more for you if I can, will post back in a bit.

*edit*

http://communities.vmware.com/thread/111953?tstart=0 user group listing

[DougBaer]

First off, I would probably lose the Microsoft cluster if you're going for a VI3 solution. I have virtualized Exchange 2003 environments around 1500 users without the ESX host breaking a sweat -- we moved from a clustered Exchange 2003 to VMs in order to reduce the management overhead and provide better DR capabilities. Using VMware HA provided acceptable hardware failure protection in that environment, and eliminated the nasty MSCS-on-ESX cluster limitations like storing Windows system drives on ESX local storage.

Second, I would look at the different roles that an Exchange 2007 server can take in the Exchange environment. The key considerations are around workload division. Many of the ancillary servers can be virtualized without issue, leaving you to spend time on the areas that matter. IMHO, this woudl be the servers with the Mailbox and Client Access roles due to the high IO requirements. Those two roles seem like good candidates to split onto separate VMs. I have seen studies from several vendors that indicate virtualizing these roles is definitely possible, as long as you follow the rules.

Consider that virtualizing the Mailbox role will definitely impact the disk and network utilization of the ESX host. Don't try to pile 30 other VMs on the same host and/or same LUNs used by the Mailbox server -- unless those VMs host low-I/O workloads and wouldn't impact or be impacted by the Mailbox server. Eliminate or reduce contention wherever possible and you should be fine.HTH

:smileylaugh:

[pfuhli]

I believe that starting with clean installations would be the better option.

Our SAN will not only serve for exchange but as well for our VI3. This will be around 50 physical servers. We also don't know about the cache yet.

[Simon4]

Hi,

We don't have the number of users you have, we are 1700 but we have virtualised our Exchange environment. We have four backend servers, 2 processor, 3.5GB memory, RAID 5 storage and two front end servers. They are hosted on 4 eight way single core servers along side 81 other VM's without any performance issues at all. If you want more detail let me know.

Kind regards

Si

[medvitz]

A few recommendations. If you have the resources, dedicate a pair of HBA ports on your ESX boxes to exchange. In addition, I'd make set up DRS so that only one Exchange Guest could reside on a given host. Both Dell and VMWare (and possibly others) have whitepapers on exchange performance in VM. Use those same configurations, if at all possible.

[jhanekom]

I'm curious about the recommendation for dedicating two HBA's to Exchange? Is this for cases where you cannot steer the paths down certain routes because of Active/Passive SANs forcing you to use MRU? Or do you foresee saturating a pair of 4Gb HBA's used for other purposes as well?

[medvitz]

This is more about dedicating some of the fiber bandwidth to exchange.

Exchange is very I/O intensive (2007 is supposed to be less so...), so

having dedicated channels could help alleviate possible bottlenecks.

This would be very dependent on your SAN config as well. For instance,

if you can't dedicate host ports on your storage arrays to this traffic,

this wouldn't make sense.

I hope this helps

Dave

[EllettIT]

http://nexus.realtimepublishers.com/SGES2K7SS.htm

Just ran across this link, might be of use... maybe?