1. ATC323
Architecting Highly Available, Geo-Redundant Cloud Solutions with Windows Azure
Graham Elliott
Asia Time Zone Director
Global Technical Evangelism and Development Team
Microsoft

2. Why? Stuff Happens You are ultimately responsible for:
Fault Tolerance
Disaster Recovery
High Availability
What do you want to protect against?

3. Recovery Point Objective (RPO)
Disaster
Last Backup or Point when data can be consistently rolled back
RPO
How far back?

4. Recovery Time Objective (RTO)
Disaster
Last Backup or Point when data can be consistently rolled back
RPO
How far back?
Systems fully recovered
RTO
How much time?

5. Other Considerations RPO RTO Performance Consistency
Geographic location
Cost
SLAs
Compliance
Last Backup or Point when data can be consistently rolled back
Systems fully recovered
Disaster
How far back?
How much time?
RPO
RTO

6. High Availability and Disaster Recovery
Hot HA
(Live/Live Config)
No Downtime
Hot DR
(Least Common)
> 5 Minutes
> 1 Hour
Warm DR
Local Fault Tolerance with Cold DR
> Few Hours $ $$
$$$
$$$$

7. Windows Azure Geo-DR Architectures

8. Cold DR (with local fault tolerance)
Client
Data Center 1
Redirect DNS
Data Center 2
Load Balancer
Load Balancer
Cloud Service …
Cloud Service
Cloud Service …
Cloud Service
Fault
Domain
Fault
Domain
Deployment
Package
Fault
Domain
Fault
Domain
Redeploy
SQL
Database
Azure
Storage
Azure
Storage
SQL
Database
Geo-Replication*
Restore BACPAC
Custom / 3rd Party
Backup
BACPAC
from DB Copy
BACPAC
from DB Copy

9. Demo
SQL Database Export
Storage Geo-Replication

10. Regions, Sub Regions and Data Centers
North America Region
Europe Region
Asia Pacific Area
N. Europe
Sub-Region
N. Central – U.S. Sub-Region
NE. China (via 21Vianet) Sub-Region
West – U.S. Sub-Region
East – U.S. Sub-Region
East Japan Sub-Region
W. Europe
Sub-Region
West Japan Sub-Region
E. China (via 21Vianet) Sub-Region
S. Central – U.S. Sub-Region
E. Asia Sub-Region
S.E. Asia
Sub-Region
Major datacenter
CDN node
Live sub-region
Announced sub-region
Partner-operated sub-region
East Australia Sub-Region
Southeast Australia Sub-Region

11. Other Building Block Business Continuity
TechEd 2013
5/12/ :09 AM
Other Building Block Business Continuity
virtual machines
Availability / load-balanced sets.
No charge if stopped.
SQL: Most HA/DR support in some form.
DR = Recreate from script/image/disk.
identity
HA and resilience within a single data center
ACS 1.0 (deprecated): Not recoverable.
ACS 2.0: Offsite daily backups provided.
Powershell based export/import.
web sites
Built in FT for Shared and Standard modes.
Failure detection and FT with single instance.
Automatic load balancing and autoscale.
DR = Redeploy.
HA and resilience within a single data center.
DB backend as per SQL Database.
DR = Redeploy.
mobile
caching
Caching: HA across fault domains.
Shared Caching: HA not supported.
DR = Redeploy.
media
HA and resilience within a single data center.
DR should focus on data stores.
DR = Redeploy.
service bus
Service namespaces cannot span DCs.
No Auto geo-replication.
Relayed: geo-replication of endpoints sample.
Brokered: Active & passive replication sample.
Client: Durable client side queue.
SQL Reporting
HA and resilience within a single data center.
DR should focus on data stores.
DR = Redeploy.
© 2013 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

12. Warm DR Client … … Geo-Replication* Restore BACPAC Custom / 3rd Party
Data Center 1
Traffic
Manager
Data Center 2
Load Balancer
Load Balancer
Cloud Service …
Cloud Service
Cloud Service …
Cloud Service
Fault
Domain
Fault
Domain
Fault
Domain
Fault
Domain
SQL
Database
Azure
Storage
Azure
Storage
SQL
Database
Geo-Replication*
Restore BACPAC
Custom / 3rd Party
Backup
BACPAC
from DB Copy
BACPAC
from DB Copy
SQL Data Sync

13. Demo
Traffic Manager
SQL Data Sync

14. Hot DR – Azure SQL Database
Client
Data Center 1
Traffic
Manager
Data Center 2
Load Balancer
Load Balancer
Cloud Service …
Cloud Service
Cloud Service …
Cloud Service
Fault
Domain
Fault
Domain
Fault
Domain
Fault
Domain
SQL
Database
Azure
Storage
Azure
Storage
SQL
Database
Custom Replication or
HA Proxy
Service Bus
Service Bus

15. Hot DR – SQL Server in a VM
Client
Data Center 1
Traffic
Manager
Data Center 2
Load Balancer
Load Balancer
Cloud Service …
Cloud Service
Cloud Service …
Cloud Service
Fault
Domain
Fault
Domain
Fault
Domain
Fault
Domain
SQL
Server in a VM
Azure
Storage
Azure
Storage
SQL
Server in a VM
Custom Replication or
HA Proxy
Backup to URL / Restore or Database Mirroring

16. SQL Server in Azure HA/DR - Scenarios
HA within Azure (single Data Center)
DR across Azure Data Centers
DR between On-Premise and Azure

17. SQL Server HA within Azure
Why?
Failure detection for SQL Server not just VM
Azure service healing
Azure upgrades S P S P VM VM
Windows Azure
(Single Data Center)

18. Technologies Supported
Technology
SQL Version
Zero Data Loss
Scope
# Secondaries
Automatic
Failover
Readable
Secondaries
Availability Groups
SQL Server 2012
Yes
(Sync Mode)
DB(s) 4
(w/ additional cluster member)
Database Mirroring
SQL Server 2008 R2
(High Safety Mode) DB 1
(w/ Witness)
Limited
(database snapshots)

19. SQL Server DR across Data CentersP
Why?
If you use multiple disks for SQL Server
If Azure storage DR doesn’t meet your needs
Freedom to test / execute DR
Windows Azure
Windows Azure

20. Technologies Supported
Technology
SQL Version
Zero Data Loss
Scope
# Secondaries
Automatic
Failover
Readable
Secondaries
Database Mirroring
SQL Server 2008 R2
SQL Server 2012
Yes
(High Safety Mode) DB 1
(w/ Witness) No
Backup to Url
SQL Server 2012 SP1 CU2
N/A
* Most customers use Async Mode (High Performance) to avoid impacting primary performance
**Async Mode only supports Force Failover to make DR (and potential data loss) a conscious decision

21. Thanks !! Large Scale failures in the cloud are rare, but happen.
Application Owners are ultimately responsible for availability and recoverability
Balance cost and complexity of HA against the risks you are willing to bear.
You also have the option to degrade features, and performance to add resiliency.

22. Resources Learning TechNet Developer Network 5/12/2019 10:09 AM
Sessions on Demand
Virtual Academy
TechNet
Developer Network
Resources for IT Professionals
Resources for Developers
© 2013 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

23. 5/12/ :09 AM
© 2013 Microsoft Corporation. All rights reserved. Microsoft, Windows and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.
© 2013 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.