Commands › Exchange Online

Start-DatabaseAvailabilityGroup

Exchange Online ExchangeOnlineManagement Start-*

Reincorporate one or more previously failed members of a database availability group (DAG).

Quick start script

# Start-DatabaseAvailabilityGroup — quick start (serv365.ai)
# 1. Connect (app-only shown; interactive: omit the certificate parameters)
Connect-ExchangeOnline -CertificateThumbprint $thumb -AppId $appId -Organization $org

# 2. Run and inspect
Start-DatabaseAvailabilityGroup -Identity <DatabaseAvailabilityGroupIdParameter> -ActiveDirectorySite <AdSiteIdParameter> -MailboxServer <MailboxServerIdParameter> | Format-List

# 3. Export for evidence / drift tracking
Start-DatabaseAvailabilityGroup | Export-Clixml .\DatabaseAvailabilityGroup-$(Get-Date -Format yyyyMMdd).xml

Syntax — 2 parameter sets

Identity

Start-DatabaseAvailabilityGroup [-Identity] <DatabaseAvailabilityGroupIdParameter> -ActiveDirectorySite <AdSiteIdParameter>
 [-ConfigurationOnly]
 [-Confirm]
 [-DomainController <Fqdn>]
 [-WhatIf]
 [<CommonParameters>]

MailboxSet

Start-DatabaseAvailabilityGroup [-Identity] <DatabaseAvailabilityGroupIdParameter> -MailboxServer <MailboxServerIdParameter>
 [-ConfigurationOnly]
 [-Confirm]
 [-DomainController <Fqdn>]
 [-WhatIf]
 [<CommonParameters>]

Parameters (7)

Parameter	Type	Required	What it controls
-Identity	DatabaseAvailabilityGroupIdParameter	yes	The Identity parameter specifies the name of the DAG being started.
-ActiveDirectorySite	AdSiteIdParameter	yes	The ActiveDirectorySite parameter specifies whether to start all DAG members in the specified site.
-MailboxServer	MailboxServerIdParameter	yes	The MailboxServer parameter specifies whether to start a single DAG member.
-ConfigurationOnly	SwitchParameter		The ConfigurationOnly switch specifies whether to update the Active Directory properties with the start action, but doesn't perform a start of the DAG or any members. You don't need to specify a value with this switch.
-Confirm	SwitchParameter		The Confirm switch specifies whether to show or hide the confirmation prompt. How this switch affects the cmdlet depends on whether the cmdlet requires confirmation before proceeding.
-DomainController	Fqdn		The DomainController parameter specifies the domain controller that's used by this cmdlet to read data from or write data to Active Directory. You identify the domain controller by its fully qualified domain name...
-WhatIf	SwitchParameter		The WhatIf switch shows what the command does without making any changes. You don't need to specify a value with this switch.

Reference facts derived from Microsoft documentation, © Microsoft, licensed CC BY 4.0; restructured with original guidance by serv365.ai.