Microsoft Exchange Architecture & Sizing

1. Exchange Architecture &
Sizing
Dave Stork
Architect @ OGD ict-
diensten
Exchange MVP
Mail: dave.stork@ogd.nl
Twitter: @dmstork
Blog: https://dirteam.com/dave
Podcast: www.theUCarchitects.com

2. Agenda
Fundamentals
Preferred Architecture
Sizing
Virtualization

3. Fundamentals

4. Fundamentals
On-prem, full cloud or Hybrid?
I’ll assume on-premises for this talk ;-)
Which version?
Exchange 2007 & 2010
– Extended Support until 2017 & 2020
– Lowest coexistence with Exchange 2000 & 2003
Exchange 2013
– Mainstream support until 2018
– Lowest coexistence with Exchange 2007
Exchange 2016
– not yet released
– Lowest coexistence with Exchange 2010

5. Fundamentals
What is necessary to run Exchange?
Active Directory
DNS
– Active Directory integrated
Certificates
– Use SHA2 certificates
Windows Server
– Use highest supported version
– Enterprise or Standard?
Server resources
– CPU & Memory
– Storage
– Network

6. Fundamentals
What might be necessary?
Load Balancer
– When more than one (Client Access) server
Reverse Proxy
– Extra security layer
– Pre-authentication
Office Web App Server
Others from business requirements

7. Outer DMZ
public IP adressing
Inner DMZ
private IP adressing Datacenter Zone
Users (Outlook, Mobile, OWA)
Exchange DAG
Reverse Proxy
(TMG)
Load balancer
File share
Witness
Office Web
App
(Optional)
Users (Outlook, Mobile, OWA)
IP-PBX
(Optional)
Lync
(Optional)
SharePoint
(Optional)
Anti
Malware

8. Fundamentals
Exchange 2010 Roles
Client Access
– HTTPS: OWA Rendering, ActiveSync etc.
Hub Transport
– SMTP transport and handling
Mailbox
Unified Messaging
– Voicemail and Auto-Attendant
Best practice: Multi role (CAS, HUB, MBX)
Edge Transport
– Perimeter network SMTP cleaning
– Non-domain joined

9. Fundamentals
Exchange 2013 Roles
Client Access
– “Just a proxy”
Mailbox
– Alle business logic; SMTP, HTTP, UM, Database
Best practice: Multi role
Edge Transport
– Perimeter network SMTP cleaning
– Non-domain joined
– Since SP1 (CU4)

10. Fundamentals
Exchange 2016 Roles
There is just one role
– However, the concept of Client Access Proxy is still
present in Exchange 2016.
– Consider 2016 an automatic 2013 multi-role
Edge Transport
– Perimeter network SMTP cleaning
– Non-domain joined

11. Infrastructuur
Database Availability Group (DAG)
“Clustering” for High Availability and Disaster Recovery
There is always one Active Copy
There can be multiple Passive Copies of a database
Max 16 (Mailbox) servers in a DAG
– Theoretically max 16 copies of DB (including Active)
Lagged DB
Recommended max 2TB per DB in DAG
– I prefer smaller database sizes even in a DAG (~300GB)
File Share Witness
– Tie breaker: the majority of votes of interconnected servers wins

12. DAG

13. Preferred Architecture

14. Preferred Architecture
What is the Preferred Architecture (PA)?
“The PA is the Exchange Engineering Team’s prescriptive approach
to what we believe is the optimum deployment architecture for
Exchange 2013, and one that is very similar to what we deploy in
Office 365”
There are two versions, one for 2013 and one for 2016
My advice: stay as close as possible to PA with your design.
Describe any deviations and why this deviation is required.

15. Namespace design

16. DAG design

18. mail.contoso.com

19. Sizing

20. Sizing
Design and validate your Exchange
environment according to business
requirements and usage.
What information do you need?
User activity
Business requirements
– High available and disaster recovery? RTO/RPO
– Growth and lifecycle of environment
– Physical or virtual?

21. Sizing
What steps are involved?
Gather user statistics
– Generate-MessageProfile.ps1
Have a general design idea including server
resources
– Find SPECInt 2006 rate of the CPU of your choice
Use the Exchange Server Role Requirements
Calculator
– Note: version and update specific
– Input user statistics
– CPU information
– Other

23. Server Configuration
/ Primary Datacenter Server
(Single Failure)
Recommended RAM Configuration 24 GB
Number of Processor Cores Utilized 2
Server CPU Utilization 18%
Server CPU Megacycle Requirements 4821
Server Total Available Adjusted Megacycles 26430
Possible Storage Architecture RAID
Recommended Transport Database Location System Disk
Host IO and Throughput Requirements / Database / Server / DAG
Total Database Required IOPS 1 66 133
Total Log Required IOPS 0 15 29
Database Read I/O Percentage 60% -- --
Background Database Maintenance Throughput Requirements 1.0 MB/s 58 MB/s 116 MB/s

24. Sizing
What steps are involved?
Adjust your design
– Other processor (or server)
– More Exchange servers
– Different quota’s
– Etc.
Use the sizing calculator again
– Evaluate, repeat, evaluate, repeat…
– Choose your optimal supported sizing

25. Sizing
And then?
Build your servers up until installing Exchange
– including all patches/updates, Exchange requirements,
antivirus, back-up agent etc..
Validate your storage with Jetstress
– This can take several days
Resolve any issues
Remove Jetstress and install Exchange
Monitor

26. Virtualization

27. Virtualization
What to consider when virtualizing?
Design as if physical, but…
Hypervisor is validated in SVVP
No dynamically expanding disks
– Exception VHDX on Hyper-V
No dynamic memory
No overcommit of memory on host
Maximum CPU overcommit ratio of 1:2 of host
– Every 1 physical core is assigned 2 times max

28. Virtualization
Hyper Threading doesn’t count
Loosened heartbeat
– If there is a requirement for migration of the host while
running etc.
Anti affinity rules
– Don’t put Exchange servers and supporting infrastructure
on the same host
No save state moves
No snapshot back-up (Only VSS)

29. Virtualization
Take NUMA boundary into account
– non-uniform memory access (NUMA)
– Fastest complex of processing unit and memory
Sometimes more smaller servers is a better fit
with virtualization
– This is also true when physical. Find your acceptable
optimal point.

30. Virtualization
Don’t deploy more Exchange VMs than
Hypervisor hosts
Consider capacity management for your
virtualization environment
– I’ve seen a lot of issues when CPU ratio was higher than
1:2
Consider physical deployment
– Total cost of ownership/operation could be lower than with
virtual

31. Microsoft Ignite 2015 sessions
Meet Exchange Server 2016
Exchange Server Preferred Architecture
Deploying Exchange Server 2016
Exchange on IaaS: Concerns, Tradeoffs, and
Best Practices
https://channel9.msdn.com/Events/Ignite/2015

32. Questions?
Mail: dave.stork@ogd.nl
Twitter: @dmstork
Blog: https://dirteam.com/dave
Podcast: www.theUCarchitects.com