Create an Availability Group (SQL Server PowerShell)

This topic describes how to use PowerShell cmdlets to create and configure an AlwaysOn availability group by using PowerShell in SQL Server 2012. An availability group defines a set of user databases that will fail over as a single unit and a set of failover partners, known as availability replicas, which support failover.

Note

For an introduction to availability groups, see Overview of AlwaysOn Availability Groups (SQL Server).

• Before you begin:  

  Prerequisites, Restrictions, and Recommendations

  Security

  Summary of Tasks and Corresponding PowerShell Cmdlets

  To Set Up and Use the SQL Server PowerShell Provider

• To create and configure an availability group, using:  Using PowerShell to Create and Configure an Availability Group

• **Examples: ** Using PowerShell to Create an Availability Group

• Related Tasks

• Related Content

Note

As an alternative to using PowerShell cmdlets, you can use the Create Availability Group wizard or Transact-SQL. For more information, see Use the New Availability Group Dialog Box (SQL Server Management Studio) or Create an Availability Group (Transact-SQL).

Before You Begin

We strongly recommend that you read this section before attempting to create your first availability group.

Prerequisites, Restrictions, and Recommendations

• Before creating an availability group, verify that the host instances of SQL Server each resides on a different Windows Server Failover Clustering (WSFC) node of a single WSFC failover cluster. Also, verify that your server instances met the other server-instance prerequisites and that all of the other AlwaysOn Availability Groups requirements are meet and that you are aware of the recommendations. For more information, we strongly recommend that you read Prerequisites, Restrictions, and Recommendations for AlwaysOn Availability Groups (SQL Server).

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Security

Permissions

Requires membership in the sysadmin fixed server role and either CREATE AVAILABILITY GROUP server permission, ALTER ANY AVAILABILITY GROUP permission, or CONTROL SERVER permission.

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Summary of Tasks and Corresponding PowerShell Cmdlets

The following table lists the basic tasks involved in configuring an availability group and indicates those that are supported by PowerShell cmdlets. The AlwaysOn Availability Groups tasks must be performed in the sequence in which they are presented in the table.

Task	PowerShell Cmdlets (if Available) or Transact-SQL Statement	Where to Perform Task*
Create database mirroring endpoint (once per SQL Server instance)	New-SqlHadrEndPoint	Execute on each server instance that lacks database mirroring endpoint. Note To alter an existing database mirroring endpoint, use Set-SqlHadrEndpoint.
Create availability group	First, use the New-SqlAvailabilityReplica cmdlet with the -AsTemplate parameter to create an in-memory availability-replica object for each of the two availability replicas that you plan to include in the availability group. Then, create the availability group by using the New-SqlAvailabilityGroup cmdlet and referencing your availability-replica objects.	Execute on the server instance that is to host the initial primary replica.
Join secondary replica to availability group	Join-SqlAvailabilityGroup	Execute on each server instance that is hosts a secondary replica.
Prepare the secondary database	Backup-SqlDatabase and Restore-SqlDatabase	Create backups on the server instance that hosts the primary replica. Restore backups on each server instance that hosts a secondary replica, using the NoRecovery restore parameter. If the file paths differ between the computers that host the primary replica and the target secondary replica, also use the RelocateFile restore parameter.
Start data synchronization by joining each secondary database to availability group	Add-SqlAvailabilityDatabase	Execute on each server instance that hosts a secondary replica.

* To perform a given task, change directory (cd) to the indicated server instance or instances.

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To Set Up and Use the SQL Server PowerShell Provider

• SQL Server PowerShell Provider

• Get Help SQL Server PowerShell

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Using PowerShell to Create and Configure an Availability Group

Note

To view the syntax and an example of a given cmdlet, use the Get-Help cmdlet in the SQL Server PowerShell environment. For more information, see Get Help SQL Server PowerShell.

1. Change directory (cd) to the server instance that is to host the primary replica.

2. Create an in-memory availability-replica object for the primary replica.

3. Create an in-memory availability-replica object for each of the secondary replicas.

4. Create the availability group.

   Note

   The maximum length for an availability group name is 128 characters.

5. Join the new secondary replica to the availability group. For more information, see Join a Secondary Replica to an Availability Group (SQL Server).

6. For each database in the availability group, create a secondary database by restoring recent backups of the primary database, using RESTORE WITH NORECOVERY.

7. Join every new secondary database to the availability group. For more information, see Join a Secondary Replica to an Availability Group (SQL Server).

8. Optionally, use the Windows dir command to verify the contents of the new availability group.

Note

If the SQL Server service accounts of the server instances run under different domain user accounts, on each server instance, create a login for the other server instance and grant this login CONNECT permission to the local database mirroring endpoint.

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Example: Using PowerShell to Create an Availability Group

The following PowerShell example creates and configures a simple availability group named MyAG with two availability replicas and one availability database. The example:

1. Backs up MyDatabase and its transaction log.

2. Restores MyDatabase and its transaction log, using the -NoRecovery option.

3. Creates an in-memory representation of the primary replica, which will be hosted by the local instance of SQL Server (named PrimaryComputer\Instance).

4. Creates an in-memory representation of the secondary replica, which will be hosted by an instance of SQL Server (named SecondaryComputer\Instance).

5. Creates an availability group named MyAG.

6. Joins the secondary replica to the availability group.

7. Joins the secondary database to the availability group.

# Backup my database and its log on the primary
Backup-SqlDatabase `
    -Database "MyDatabase" `
    -BackupFile "\\share\backups\MyDatabase.bak" `
    -ServerInstance "PrimaryComputer\Instance"

Backup-SqlDatabase `
    -Database "MyDatabase" `
    -BackupFile "\\share\backups\MyDatabase.log" `
    -ServerInstance "PrimaryComputer\Instance" `
    -BackupAction Log 

# Restore the database and log on the secondary (using NO RECOVERY)
Restore-SqlDatabase `
    -Database "MyDatabase" `
    -BackupFile "\\share\backups\MyDatabase.bak" `
    -ServerInstance "SecondaryComputer\Instance" `
    -NoRecovery

Restore-SqlDatabase `
    -Database "MyDatabase" `
    -BackupFile "\\share\backups\MyDatabase.log" `
    -ServerInstance "SecondaryComputer\Instance" `
    -RestoreAction Log `
    -NoRecovery

# Create an in-memory representation of the primary replica.
$primaryReplica = New-SqlAvailabilityReplica `
    -Name "PrimaryComputer\Instance" `
    -EndpointURL "TCP://PrimaryComputer.domain.com:5022" `
    -AvailabilityMode "SynchronousCommit" `
    -FailoverMode "Automatic" `
    -Version 11 `
    -AsTemplate

# Create an in-memory representation of the secondary replica.
$secondaryReplica = New-SqlAvailabilityReplica `
    -Name "SecondaryComputer\Instance" `
    -EndpointURL "TCP://SecondaryComputer.domain.com:5022" `
    -AvailabilityMode "SynchronousCommit" `
    -FailoverMode "Automatic" `
    -Version 11 `
    -AsTemplate

# Create the availability group
New-SqlAvailabilityGroup `
    -Name "MyAG" `
    -Path "SQLSERVER:\SQL\PrimaryComputer\Instance" `
    -AvailabilityReplica @($primaryReplica,$secondaryReplica) `
    -Database "MyDatabase"

# Join the secondary replica to the availability group.
Join-SqlAvailabilityGroup -Path "SQLSERVER:\SQL\SecondaryComputer\Instance" -Name "MyAG"

# Join the secondary database to the availability group.
Add-SqlAvailabilityDatabase -Path "SQLSERVER:\SQL\SecondaryComputer\Instance\AvailabilityGroups\MyAG" -Database "MyDatabase"

Related Tasks

To configure a server instance for AlwaysOn Availability Groups

• Enable and Disable AlwaysOn Availability Groups (SQL Server)

• Create a Database Mirroring Endpoint for AlwaysOn Availability Groups (SQL Server PowerShell)

To configure availability group and replica properties

• Change the Availability Mode of an Availability Replica (SQL Server)

• Change the Failover Mode of an Availability Replica (SQL Server)

• Create or Configure an Availability Group Listener (SQL Server)

• Configure the Flexible Failover Policy to Control Conditions for Automatic Failover (AlwaysOn Availability Groups)

• Specify the Endpoint URL When Adding or Modifying an Availability Replica (SQL Server)

• Configure Backup on Availability Replicas (SQL Server)

• Configure Read-Only Access on an Availability Replica (SQL Server)

• Configure Read-Only Routing for an Availability Group (SQL Server)

• Change the Session-Timeout Period for an Availability Replica (SQL Server)

To complete availability group configuration

• Join a Secondary Replica to an Availability Group (SQL Server)

• Manually Prepare a Secondary Database for an Availability Group (SQL Server)

• Join a Secondary Database to an Availability Group (SQL Server)

• Create or Configure an Availability Group Listener (SQL Server)

Alternative ways to create an availability group

• Use the New Availability Group Wizard (SQL Server Management Studio)

• Use the New Availability Group Dialog Box (SQL Server Management Studio)

• Create an Availability Group (Transact-SQL)

To troubleshoot AlwaysOn Availability Groups configuration

• Troubleshoot AlwaysOn Availability Groups Configuration (SQL Server)

• Troubleshoot a Failed Add-File Operation (AlwaysOn Availability Groups)

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Related Content

• **Blogs: **

  AlwaysON - HADRON Learning Series: Worker Pool Usage for HADRON Enabled Databases

  Configuring AlwaysOn with SQL Server PowerShell

  SQL Server AlwaysOn Team Blogs: The official SQL Server AlwaysOn Team Blog

  CSS SQL Server Engineers Blogs

• **Videos: **

  Microsoft SQL Server Code-Named "Denali" AlwaysOn Series,Part 1: Introducing the Next Generation High Availability Solution

  Microsoft SQL Server Code-Named "Denali" AlwaysOn Series,Part 2: Building a Mission-Critical High Availability Solution Using AlwaysOn

• **Whitepapers: **

  Microsoft SQL Server AlwaysOn Solutions Guide for High Availability and Disaster Recovery

  Microsoft White Papers for SQL Server 2012

  SQL Server Customer Advisory Team Whitepapers

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See Also

Concepts

The Database Mirroring Endpoint (SQL Server)

Overview of AlwaysOn Availability Groups (SQL Server)