1. Clusters Your Way.™Clusters Your Way.™
Highly Available SQL Deployments in the Cloud -
What You Need to Know
Moving business critical applications, such as Microsoft SQL
Server, to virtual server and cloud environments, requires high
availability and a solid disaster protection plan.
2. Clusters Your Way.™
Author
ClusteringForMereMortals.com
MSDN Press Blog
Microsoft Cloud and Datacenter MVP 2010-Present
Multisite Clusters, Azure, SQL Server
SIOS Technology Senior Technical Evangelist
Focused on High Availability and Disaster Recovery since
2004
Contact
Twitter @daveberm
Email david.bermingham@us.sios.com
Who is Dave Bermingham?
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3. Clusters Your Way.™
Business Critical Workloads
Moving Rapidly to The New Data Center
IT Flexibility
& Agility
Traditional Data Center The New Data Center
Physical Virtual Cloud
Private
Cloud
Public
Cloud
Hybrid
Cloud
Physical
4. Clusters Your Way.™
Gartner predicts that the bulk of new IT
spending by 2016 will be for cloud
computing platforms and applications and
that nearly half of large enterprises will have
cloud deployments by the end of 2017.
High availability and disaster protection in
cloud environments is a critical need.
Source: Gartner Newsroom
Critical applications are moving
to the cloud
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5. Clusters Your Way.™
The myth: Public cloud
deployments are automatically
high availability environments
where application downtime is
negligible.
The truth: Clouds are not high
availability environments unless
you add HA protection.
Myth #1: Clouds are HA environments
“The average unavailability
of cloud services is 10 hours
per year or more, while the
average availability is
estimated to be 99.9% (9
hours or more than a day of
downtime), far less than the
expected availability of
business critical
applications.” – Josh Whittaker, ZDNet
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10. Clusters Your Way.™
Redundancy is not enough.
Web and application services
in different geographic
locations in the cloud
Load balancers in front of
Web or Application servers
Fault Domain Fault Domain
What about the Data Tier?
Microsoft SQL Server
cannot be made redundant
with a simple load balancer
and multiple instances in
different “Fault Domains”
Databases such as SQL Server
need additional configuration
11. Clusters Your Way.™
What can you do?
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Azure
Update
Domain
SQL1
Update
Domain
SQL2
Virtual Network
Replication
Transactional applications
such as SQL, Oracle,
MySQL, SAP, etc. require
additional configuration
Some applications can
simply be load balanced
across multiple Availability
Zones/Fault Domains.
WEB1 WEB2
Load Balancer
12. Clusters Your Way.™
The Enabling Technology
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https://azure.microsoft.com/en-us/documentation/articles/virtual-machines-windows-sql-high-availability-dr/
13. Clusters Your Way.™
AlwaysOn
Availability
Groups
#SANLess
Cluster
Support SQL Standard Edition 0 4
Distributed Transactions 0 4
Unlimited Databases 0 4
Protects System Databases
(Master, MSDB, etc)
0 4
Eases Database Administration 0 4
Support more than 2-nodes in
failover configuration
0 4
Replicates Data other than SQL 0 4
Readable Secondary 4 0
#SANLess Cluster vs. Availability Groups
14. Clusters Your Way.™
The myth: You cannot protect business critical applications in
a public or private cloud by using a cluster.
The truth. Traditional HA in a physical deployment is with a
failover cluster using a shared storage (SAN). Public clouds
(ie, Amazon EC2, Azure) have no concept of a cluster-aware
shared storage.
You can create a SANLess cluster for HA and DR protection in
a cloud environment.
Myth #2: You can’t have failover cluster
protection in a cloud
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15. Clusters Your Way.™
Traditional failover clustering
requires shared storage
High Availability Clusters in Cloud
Environments
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SQL
SERVER
FAILOVER
SQL
SERVER
storage
storage storageREPLICATION
SQL
SERVER
REPLICATION
SANLess clusters provide
synchronized redundant storage
for cloud environments without SAN
SANLess cluster software
presents cloud storage to
WSFC as a SAN
But shared storage is not
available in public clouds or
practical in private clouds
16. Clusters Your Way.™
It comes with Windows Server
Familiar to Windows IT Admins
Easy to Create a Failover Cluster
No Additional Training or Specialized Skills
Compatible with SQL Server and other Windows
Applications
Why Do Customers Like Failover
Clustering?
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17. Clusters Your Way.™
The myth: Creating an HA environment in a cloud requires
complex scripting, specialized skills, or added complexity.
The truth: A SANless HA cluster in a cloud takes can be built
in minutes without specialized skills.
Use Standard Edition instead of costly Enterprise Edition of
SQL
Failover Clustering comes included with Windows Server
2012/2012R2
Cluster Validation Wizard eliminates the need for the
Hardware Compatibility List
Azure Resource Manager Deployment Templates
Myth #3: HA in a cloud is costly
and complicated
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18. Clusters Your Way.™
What About Failure of Entire Regions?
Azure East
Update
Domain
Update
Domain
Web
Application
Web
Application
SQL Server Failover Cluster Instance
SQL1 SQL2Replication
Azure West
Update
Domain
SQL3
In the event an entire
region fails you will need a
way to rapidly recover with
minimal data loss
High
Availability
Locally
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19. Clusters Your Way.™
What About Failure of “The Cloud”?
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Azure East
Fault Domain Fault Domain
Web
Application
Web
Application
SQL Server Failover Cluster Instance
SQL1 SQL2Replication
Menlo Park Data
Center
SQL3
Virtual Private Network
In the event of a
“Cloud Wide” outage
you will need a way
to recover quickly
with minimal data
loss
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20. Clusters Your Way.™
What About Failure of “The Cloud”
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Azure West
Fault Domain Fault Domain
Hybrid Cloud Multisite Cluster
SQL1 SQL2Replication
Amazon West
SQL3
Virtual Private Network
You may consider
spanning multiple
cloud providers
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