4. Configuring Database Availability Group Properties
You can use the Exchange Management Console or the Exchange
Management Shell to configure the properties of a database availability
group, including the witness server and witness directory used by the
database availability group. Using the Exchange Management Shell, you
can configure additional properties, such as encryption and compression
settings, network discovery, the TCP port used for replication,
alternate file share witness settings, and data center activation
coordination mode.
To view or modify the properties of an availability group, complete the following steps:
-
In the Exchange Management Console, expand the Organization
Configuration node and then select the related Mailbox node. In the
results pane, select the Database Availability Group tab to view
existing availability groups.
-
Right-click the database availability group you want to work with and then select properties.
-
In the Properties dialog box, shown in Figure 5
you'll see a list of member servers, the witness server's fully
qualified domain name, and the location of the witness directory on the
witness server.
-
Using the Witness Server text box, you can specify a new witness
server by entering the fully qualified domain name of the new witness
server. This server should be in the same Active Directory forest as
the member servers and cannot be a current or future member of the
database availability group.
-
Using the Witness Directory text box, you can specify a new witness
directory on the witness server. If the directory does not exist, it
will be created on the witness server.
-
Click OK.
In the Exchange Management Shell, you can configure properties of database availability groups using the Set-DatabaseAvailabilityGroup cmdlet. Example 6 provides the syntax and usage.
Example 6. Set-DatabaseAvailabilityGroup cmdlet syntax and usage
Syntax
Set-DatabaseAvailabilityGroup -Identity DAGName
[-DatabaseAvailabilityGroupIpAddresses IPAddresses]
[-DatacenterActivationMode {"Off"|"DagOnly"}]
[-DiscoverNetworks] [-DomainController FullyQualifiedName]
[-NetworkCompression {"Disabled"|"Enabled"|"InterSubnetOnly"|"SeedOnly"}
[-NetworkEncryption {"Disabled"|"Enabled"|"InterSubnetOnly"|"SeedOnly"}
[-ReplicationPort TCPPort] [-AlternateWitnessServer ServerName]
[-AlternateWitnessServerDirectory DirectoryPath]
[-WitnessServer ServerName] [-WitnessServerDirectory DirectoryPath]
Usage
Set-DatabaseAvailability -Identity "EastCampusDAG1"
-NetworkCompression "Enabled" -NetworkEncryption "Enabled"
-ReplicationPort 33898 -DatacenterActivationMode "Off"
Options for working with encryption, compression.
Options that weren't discussed include the datacenter activation
coordinator mode, the alternate witness server, and alternate witness
server directory. These options can be used as part of a datacenter
switchover process. The alternate witness server must not be a part of
the database availability group.
The data-center
coordinator mode should be set for all database availability groups
with three or more members that are extended to two or more physical
locations. This mode cannot be enabled for groups with less than three
members. When the datacenter coordinator is enabled, you can start,
stop, and restore member servers in an availability group individually
or collectively using the following:
-
Start-DatabaseAvailabilityGroup
Activates member
Mailbox servers in a recovered data center after a data-center
switchover, as part of the failback process to the recovered data
center. This command sets the configuration and state so that the
servers are incorporated into the operating database availability group
and joined to the group's cluster. You use the –MailboxServer parameter
to start a specific member server or the –ActiveDirectorySite parameter
to start all members in a particular site.
Start-DatabaseAvailabilityGroup -Identity DAGName
[-MailboxServer ServerName | -ActiveDirectorySite SiteName]
[-ConfigurationOnly <$true | $false>]
[-DomainController FullyQualifiedName]
Note
You can also reactivate servers
from a previously failed datacenter that has been restored to service.
Before you can reactivate member Mailbox servers in a primary data
center, the servers must first be integrated back into the operational
database availability group. You reintegrate servers by running the
Start-DatabaseAvailabilityGroup cmdlet and then using the
Move-ActiveMailboxDatabase cmdlet to activate databases in the primary
data center.
-
Stop-DatabaseAvailabilityGroup
Deactivates member
Mailbox servers after a datacenter switchover. You use the
–MailboxServer parameter to deactivate a specific member server or the
–ActiveDirectorySite parameter to deactivate all members in a
particular site.
Stop-DatabaseAvailabilityGroup -Identity DAGName
[-MailboxServer ServerName | -ActiveDirectorySite SiteName]
[-ConfigurationOnly <$true | $false>]
[-DomainController FullyQualifiedName]
-
Restore-DatabaseAvailabilityGroup
Activates member
Mailbox servers in a standby data center. Typically, this process is
performed after the failure or deactivation of the active member
servers in a primary data center. You use the –ActiveDirectorySite
parameter to activate all members in a particular site.
Restore-DatabaseAvailabilityGroup -Identity DAGName
[-ActiveDirectorySite SiteName]
[-AlternateWitnessServer ServerName]
[-AlternateWitnessDirectory DirectoryPath]
[-DomainController FullyQualifiedName]
