1. SQL Server AlwaysOn Availability Groups DrillDown
4/20/2018
SQL Server AlwaysOn Availability Groups DrillDown
Ross Loforte
Technology Architect
Microsoft Corporation
© 2012 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.

2. Setting the Stage AlwaysOn ≠ Availability Groups
AlwaysOn = { SQL Server Failover Cluster Instances, Availability Groups }
Availability Groups ≠ Database Mirroring
© 2012 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.

3. Agenda Looking Back Mission-Critical Availability
4/20/2018
Agenda
Looking Back
Mission-Critical Availability
SQL Server 2012 HA/DR Technologies
Availability Groups
Benefits
Concepts
Architecture
Flexible Failover Policy
Readable Secondaries and Backup on Secondaries
Application Connectivity and Failover
Considerations
Summary
© 2012 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.

4. SQL Server 2008 High Availability & Disaster Recovery Technologies
4/20/2018
SQL Server 2008 High Availability & Disaster Recovery Technologies
Database Mirroring
Transactional Replication
Log Shipping
Windows Clustering
© 2012 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.

5. Looking Back HA/DR Topology
Backups
Database
Mirroring
Log
Shipping

6. Mission-Critical Availability
Reliable
Detects failures reliably
Able to handle multiple failures
Unified solution
Easy to configure, manage, and monitor
Integrated
Flexible
Reuse existing investments
SAN/DAS environments
Efficient
Allows using HA hardware resources
Fast seamless failover

7. AlwaysOn What is AlwaysOn?
4/20/2018
AlwaysOn
What is AlwaysOn?
A new comprehensive high availability and disaster recovery solution in SQL Server 201 provides
Instance level protection: Failover Cluster Instances
Primary/Secondary server
Each node shares a copy of the DB
Database level protection: Availability Groups (AG)
Unit of failover
Databases belong to an AG
© 2012 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.

8. AlwaysOn SQL Server 2012 HA/DR technologies Failover Cluster Instances
for servers
Availability Groups
for groups of databases
Failover Cluster Instances
for servers
Availability Groups
for groups of databases
Pre-existent
Server failover
Minutes
Useful in consolidation scenarios
Shared Storage (SAN / SMB)
Failover takes minutes
Multi-Node Clustering
Passive secondary nodes
SQL Server 2012 EE
Multi-database Failover
Seconds
Direct attached storage
Failover takes seconds
Multiple Secondaries
Active Secondaries

9. Benefits Higher Data Protection Higher Availability
Multiple sync (no data loss) secondaries
Automatic Page Repair
Lower RPO for DR secondaries through continuous log synchronization (w/ compression)
Higher Availability
Fast app failover to any secondary through Listener
More Cost-Effective
Active Secondaries: Read Workloads & Backups
Near real-time data through continuous log synchronization (no snapshots)
Easier Configuration, Management, and Monitoring
Single solution
Multiple databases
Multiple replicas
Unified configuration, management, and monitoring

10. Availability Group Concepts
Databases: No limit (recommended: max 100 DBs in AGs, max 10AGs)
Availability Replicas: 5 (including primary)
Failure Condition Level: 1 (simple failures) to 5 (simple & complex failures)
Listener Virtual Network Name
Availability Replica
Role: Primary / Secondary
Availability Mode: Sync / Async
Failover Mode: Automatic / Manual / Force
Allow Connections: Read_Write, Read_Only, No

11. AG HA/DR Topology DR HA Reports Backups Sync Log
AlwaysOn-SRV5
Reports
AlwaysOn-SRV3
Backups
AlwaysOn-SRV4
AlwaysOn-SRV2
Sync Log
Synchronization
Async Log Synchronization

12. HA/DR Topology – WF Cluster Configuration
Witness File Share
Vote = 1 DR HA
AlwaysOn-SRV5
Vote = 0
Reports
AlwaysOn-SRV3
Vote = 1
Backups
AlwaysOn-SRV4
Vote = 0
AlwaysOn-SRV2
Vote = 1
Sync Log
Synchronization
Async Log Synchronization

13. Availability Groups use Windows Server Failover Cluster
WSFC is Microsoft’s Availability Platform
Hyper-V, Exchange, MSMQ, SQL Server AlwaysOn, 3rd party apps
What for?
Inter-node health detection
Distributed store for settings
State change notifications
Failover coordination
© 2012 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.

14. Cluster Considerations
Cluster Members must be in same Windows domain
Cluster needs quorum to avoid split brain
The number of voting members determines the cluster tolerance to failures
Configuring cluster quorum:
Select cluster members to vote
Primary
Auto failover target
Other nodes in local data center (not necessarily hosting SQL Server instances)
Select quorum type:
Odd number of votes, use “Node Majority”
Even number of votes
a) Add an additional node and use “Node Majority”
b) Add a file share and use “Node and File Share Majority”
© 2012 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.

15. Flexible Failover Policy
Failure level for automatic failover (cumulative)
1 – SQL Server process is down
2 – SQL Server is unresponsive (configurable threshold to receive health diagnostics exceeded - default 30s)
3 – Critical SQL Server errors (e.g. Write AVs, orphaned spinlocks, etc)
4 – Moderate SQL Server errors (e.g. persistent OOM conditions)
5 – Any internal SQL Server error (e.g. unsolvable deadlock)
© 2012 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.

16. Flexible Failover Policy - FailureConditionLevels
5 – Failover/restart on any qualified failure conditions
Query Processing errors
4 – Failover or restart on moderate SQL Server errors
Resource errors
3 – Failover or restart on critical SQL Server errors
System errors
2 – Failover or restart on server unresponsive
No response from sp_server_diagnostics
1 – Failover or restart on server down
Service is down
0 – No Automatic Failover or restart
© 2012 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.

17. Availability Group Architecture
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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.

18. AG Considerations Failover of dependencies outside User Databases
Logins
Use Users w/Passwords (Contained Databases)
Linked Servers
Create in all replicas
Agent/Replication Jobs
Add condition to exit if not primary
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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.

19. Offloading Read Workloads - Before
Database Mirroring
Transactional Replication
Run on a subscriber
Pros:
Large number of subscribers
Targeted indexes
Cons:
Separate solution to configure/manage
Replication latency
No failover of read workloads
Run on primary
Impacts workload
Run on mirror w/snapshots
Data Staleness
Additional management
No failover of read workloads
© 2012 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.

20. Offloading Read Workloads - Now
SQL Server
Primary
DB2
DB1
Up to 4 secondaries
Sync or async
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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.

21. Readable Secondary – Data Latency
DB1
DB1
Log Capture
Network
Log Capture
Log Receive
Primary
Secondary
Log Pool
Commit/Log Block Write
Redo Thread
Log Cache
Log Cache
Redo Pages
Log Flush
Log Hardened
DB1 Log
DB1 Data
Acknowledge Commit
DB1 Log
DB1 Data
Secondary read is always behind primary during transaction activity
© 2012 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.

22. Readable Secondary: Considerations
DB1
Log Apply
Impact on RTO
Reporting workload can take resources away from REDO thread
Can impact the recovery time(RTO)
Redo Thread
Log Cache
Mitigation
User resource-governor to control resources taken by reporting workload
If using combination of sync/Async secondary, offload reports to Async Secondary.
Redo Pages
DB1 Log
DB1 Data
Reports
Resource Intensive
(IO, Memory, CPU)
© 2012 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. Query Optimization on Active Secondary
Query optimization relies on statistics
Created by indexes and read workloads
Statistics created on primary are redone on secondary
But, read workloads at secondaries are different from
primary workloads
Auto-create statistics on secondary
Store on TempDB
Remove on failover, restart, or DROP STATISTICS
© 2012 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.

24. Creating Backups - Before
Database Mirroring
R/W workload
Failed
Backups
Backups
Primary
Secondary
Only on primary
Impacts primary workload
Fails after failover
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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.

25. Backups on Secondaries - AG
Active
Secondary
Backups
R/W workload
Active
Secondary
Backups
Backups
Primary
© 2012 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.

26. Backup Capabilities Recovery Advisor Backups from any replica
Synchronous or asynchronous secondaries
Primary backups still work
Adds capacity to primary server by off- loading backups to a replica
Log backups done on all replicas from a single log chain
Recovery Advisor makes restores simple
Differential backups are not supported on secondary
Only Copy-only full backups are supported on secondary; only distinction is the differential bitmap clearing
© 2012 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.

27. Client Connectivity Read / Write Workload Read Only Workload
4/20/2018
Client Connectivity
Read / Write Workload
Connecting using AG Listener
Read Only Workload
Connection using VNN and ApplicationIntent=ReadOnly
Connection to the secondary instance directly
ReadOnly Routing
Multi subnet failover scenario:
New client libraries => MultiSubnetFailover=True
Client
AG Listener
Read/Write Workload
If you already have FAILOVER_PARTNER in the connection string, and can’t change the connection string, it will continue to work, provided:
There are only two replicas – primary and one secondary, and
The replicas have been set to NOT “Allow All Connections” in secondary role
If using new client libraries, use MultiSubnetFailover=True in the connection string
Read Only Workload
If using legacy client libraries:
Set the “Connection Mode in Secondary Role” for the AG replicas to “Allow All Connections”
Connect directly to the secondary instance
If using new client libraries:
Set the “Connection Mode in Secondary Role” for the AG replicas to “Allow ReadOnly Connections”
Define Routing List for the AG (to take advantage of ReadOnly Rerouting)
Use the AG VNN (Listener) to connect to the Availability Group, AND
Specify ApplicationIntent=ReadOnly in the connection string
If using new client libraries, use MultiSubnetFailover=True in the connection string
Primary
Secondaries
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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.

28. Client Connectivity 1 Virtual IP per subnet Part of AG resource group
Seamless connectivity to primary through Listener
Virtual Network Name
1 Virtual IP per subnet
Cluster resource
Part of AG resource group
Fails over with AG (binds to network interface)
ServerA
ServerB
ServerC HR DB HR DB HR DB
AG_HR
AG_Listener
Primary
Secondary
Primary
Secondary
Secondary
Connection retries
Data Source=HR_VNN;
Initial Catalog=HRDB
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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.

29. Configuring Secondary as Readable
ALLOW_CONNECTIONS setting NO
Don’t allow connections
ALL
Allow all connections
READ_ONLY
Only allow connections specifying READ_ONLY intent
ALTER AVAILABILITY GROUP ag_name
MODIFY REPLICA ON 'server_name'
WITH (
SECONDARY_ROLE (
ALLOW_CONNECTIONS = { NO | ALL | READ_ONLY } ) )
© 2012 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.

30. Configuring Routing of Read-Only Connections
Configure Routing URL for each secondary
Endpoint for read-only connections
ALTER AVAILABILITY GROUP ag_name
MODIFY REPLICA ON 'server_name'
WITH (
SECONDARY_ROLE (
READ_ONLY_ROUTING_URL = ‘TCP://system-address:port’ ) )
© 2012 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.

31. Configuring Routing of Read-Only Connections
Create Routing List at each replica that can be primary
List of readable secondaries
Primary returns first one available
Load balancing not offered
ALTER AVAILABILITY GROUP ag_name
MODIFY REPLICA ON 'server_name'
WITH (
PRIMARY_ROLE (
READ_ONLY_ROUTING_LIST = {'server_name' [,..n]} ) )

32. Replication And AlwaysOn
4/20/2018
Replication And AlwaysOn
What is supported?
Server roles
Publisher: yes
Distributor: no
Subscriber: yes
Types of replication
Transactional: yes
Peer to peer, bi-directional: no
Queued and immediate updating subscribers: no
Merge: yes
Snapshot: yes
Republishing topologies: no
© 2012 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.

33. AlwaysOn Monitoring Catalog View DMV are named sys.dm_hadr_*
sys.availability_groups
sys.availability_replicas
DMV are named sys.dm_hadr_*
Provides detailed information about data movement states and replica states
Performance Monitor Counter Objects
SQLServer:Database Replica
SQLServer:Availability Replica
AlwaysOn Dashboard provides the aggregated view across the layers and is built on top of the above infrastructure

34. Availability Groups Dashboard

35. System Center Availability Groups

36. System Center Availability Replicas

37. System Center Database Replicas

38. Summary for Availability Groups
All SQL servers (including the secondary in the DR site) in the same Windows domain
One Windows Server Failover Cluster spreads over the primary and DR sites
All the databases must be in FULL recovery model
The unit of failover (for local HA, as well as DR) is at the AG level, i.e., group of databases – not the instance
Consider using Contained Database for containing logins for failover
For jobs and other objects outside the database, simple customization needed
No delayed apply on the secondary like log shipping
Regular log backup job is required to truncating the log
AlwaysOn Dashboard
System Center Operations Manager
New Tools for Monitoring & Alerting

39. for attending this session
Thank you
for attending this session

40. Resources AlwaysOn Team Blog http://blogs.msdn.com/b/sqlalwayson/
SQL Server 2012 Whitepapers
© 2012 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.

41. 4/20/2018
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista 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.
© 2012 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.