PureMessage for Microsoft Exchange 2013 and 2016
13 Appendix A: Deploying PureMessage for Microsoft Exchange clusters
13.1 How PureMessage for Microsoft Exchange works with Exchange clusters
PureMessage for Microsoft Exchange incorporates a cluster-aware service that can be installed across multiple nodes. This allows PureMessage for Microsoft Exchange to be used with clustered
Microsoft Exchange servers and to take advantage of the increased resilience that a cluster offers.
Clustered systems are inherently more complicated than non-clustered systems and we recommend that you read the whole of this section before starting to install PureMessage for
Microsoft Exchange on a cluster.
If you still have questions about installing PureMessage for Microsoft Exchange on a cluster after reading this section, contact Sophos technical support.
13.2 Before you install
13.2.1 Database requirements
For cluster server installations, PureMessage for Microsoft Exchange cannot use a local MSDE or
SQL Server Express instance.
Alternatively, you may connect to any one of the following:
• A local clustered virtual SQL Server instance
• A remote SQL Server instance
• A remote MSDE or SQL Server Express instance
Note
In cluster scenarios, remote MSDE is not supported due to performance issues.
Note
PureMessage for Microsoft Exchange 4.0.4 and later supports TLS 1.2. Using TLS to connect to a
SQL Server database requires server side changes, see knowledge base article 132092 .
More than one PureMessage for Microsoft Exchange group or cluster can share a remote database.
13.2.2 Installation requirements
When installing PureMessage for Microsoft Exchange on nodes in a cluster, make sure that you meet the following requirements:
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PureMessage for Microsoft Exchange 2013 and 2016
• The path to the installation folder must be identical on each node.
• The IIS websites present on each node of the cluster must be identical. In particular, the allocated port numbers of each site must be the same across nodes.
13.3 Installation procedure on DAGs
Database Availability Groups (DAGs) are used for implementing high availability in Exchange.
• For DAGs, PureMessage for Microsoft Exchange uses DFS Replication (DFSR) to copy quarantine files between nodes. If you are using DAGs with Exchange in a high availability environment with multiple Transport Servers, these servers must be part of a Microsoft cluster. This allows
PureMessage for Microsoft Exchange to replicate quarantine files using DFSR.
• The PureMessage for Microsoft Exchange service should be installed on each DAG member one after another, but not simultaneously.
• If a DAG member has PureMessage for Microsoft Exchange installed and if it is added or removed from the DAG, then PureMessage for Microsoft Exchange must be reinstalled on that server. This is required so that the replication settings on the server are updated.
To maintain Exchange availability during the reinstallation of PureMessage for Microsoft
Exchange, the mailbox databases hosted on the server should be moved to an alternative server in the DAG.
13.4 Uninstalling PureMessage for Microsoft
Exchange from a cluster
All PureMessage for Microsoft Exchange administration consoles (if running) need to be closed
from all servers before uninstalling. Follow instructions in Uninstalling PureMessage for Microsoft
Exchange (page 26).
13.5 Administering PureMessage for Microsoft
Exchange on a cluster
Several PureMessage for Microsoft Exchange servers may be arranged into a group and administered together from a single PureMessage for Microsoft Exchange console. All
PureMessage for Microsoft Exchange servers in a group have the same policy settings applied to them, that is, when a policy change is made it is automatically applied to all the servers in the group.
13.5.1 Requirements and limitations
• The number of PureMessage for Microsoft Exchange servers in a group is limited by users' network bandwidth, and by SQL Server database resource limits.
• All group members need to also be members of the same domain.
• The ability to administer PureMessage for Microsoft Exchange servers from the remote console is directly dependent on the reliability of user network and database server connections.
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PureMessage for Microsoft Exchange 2013 and 2016
13.5.2 Using the PureMessage for Microsoft Exchange administration console
To manage a group of PureMessage for Microsoft Exchange servers, the PureMessage for
Microsoft Exchange console should connect to any server in the group. When policy changes are made, they will be automatically applied to all services in the group. Additionally, the activity monitor and dashboard screens will display status information for all the servers in the group:
To manage a different group of PureMessage for Microsoft Exchange servers from the same console, it is necessary to disconnect from the current group and reconnect to a server from the new group.
To do this, on the PureMessage for Microsoft Exchange toolbar, click on the Select server icon.
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