Use the Custom Installation option to install PureMessage on two or more servers. This option provides the flexibility to assign server roles (described below) to any number of servers in a network.
Server roles can be configured in a variety of combinations. You can distribute these roles among multiple servers however you choose. For example, in a two-server configuration, you may want to install the Centralized Server Manager and Database Server roles on the first server and the Mail Filter and Mail Transfer Agent roles on the second server. See the "Deployment Strategies" section of the Getting Started Guide for other configuration scenarios.
Select from the following roles:
Centralized Server Manager (CSM)
The Centralized Server Manager role installs the main interface for configuring the PureMessage network. The server running the CSM role must be the first server that is set up. This role must be installed on the same server as the Database Server role.
The Database Server role installs the PureMessage database for use with DBMS-based quarantines and for PureMessage reporting functions. TheDatabase Server role and the Centralized Server Manager role must be installed on the same server. Sophos does not recommend installing both the Database Server role and the Mail Filter role on the same server. In multi-server deployments, you must set up the Centralized Server Manager role and the Database Server role before installing any Mail Filter role to ensure proper synchronization of PureMessage resources.
End User Web Interface Server/Groups Web Interface Server
The End User Web Interface makes it possible for end users to manage their own quarantine, whitelists, and blacklists. Smaller PureMessage installations may run this role with the Database Server role, while larger installations should distribute these roles across multiple machines. The Groups Web Interface role, which is installed along with the End User Web Interface role, gives a global administrator the option of delegating administrative responsibilities to "group" administrators based on groups/domains and/or roles.
The Mail Filter role installs the PureMessage milter. This role is typically used in combination with the Mail Transfer Agent role to scan and filter mail for viruses and spam. Larger installations will likely have several mail filter servers.
Mail Transfer Agent
The Mail Transfer Agent server role installs the third-party mail transfer agent (MTA) software (sendmail or Postfix). The MTA receives incoming SMTP connections and sends the messages through the PureMessage mail filter. The Mail Transfer Agent role is typically installed on the same server as the Mail Filter role. In a multi-server deployment, the MTA role must also exist on the server where the CSM role is installed.
During a Custom Installation, you are prompted to choose either sendmail or Postfix as the mail transfer agent. The PureMessage installer only installs the versions of PureMessage and sendmail included with the PureMessage distribution. See "Configuring an External Sendmail Installation" or "Configuring an External Postfix Installation" in the Getting Started guide for instructions on configuring an existing sendmail, Sendmail Switch or Postfix installation. If you are not sure which type of installation to use, see "Which Mail Transfer Agent Should I Use?" in the PureMessage Sophos Knowledgebase.
The Oracle Communications Messaging Exchange Server mail transfer agent is not part of the PureMessage distribution and must be installed separately. For information about configuring this MTA, see "Configuring PureMessage for Oracle Communications Messaging Exchange Server" in the Sophos Knowledgebase.
During installation, PureMessage automatically adjusts the PostgreSQL database in an attempt to improve performance. If the adjustments are successful, PureMessage displays a confirmation message. Depending on the shared memory configuration of your system, however, additional manual steps may be required.
If your system settings are not within the recommended range, PureMessage tries to make the necessary adjustments. In some cases, the updated settings are saved to file named postgresql.conf.recommended. You can accept these settings by renaming the file to postgresql.conf. If your system does not meet even the minimum requirement for shared memory, a error message is displayed. For more information, see "Tuning PostgreSQL for PureMessage" in the Sophos Knowledgebase.