Operating Principles

The component is designed to establish connections to Doctor Web update servers to check for updates for virus databases and the Dr.Web Virus-Finding Engine scan engine, database of web resource categories, and the anti-spam component. The lists of servers which constitute an available update zone are stored in a special file (the file is signed to prevent modification). Only basic and digest authentication are supported for connection to Doctor Web update servers.

If Dr.Web for UNIX Mail Servers is not connected to the centralized protection server or is connected to the server in the mobile mode, Dr.Web Updater is automatically started by the Dr.Web ConfigD configuration daemon. The startup is performed at periods specified in the settings. The component can be also started by the configuration daemon if the appropriate command is received from a user (unscheduled update).

When updates become available on the servers, they are downloaded to the <var_dir>/cache directory (for GNU/Linux—var/opt/drweb.com/cache), after that they are moved to the working directories of Dr.Web for UNIX Mail Servers.

By default, all updates are performed from the updating zone which is common for all Dr.Web products. The list of the servers used by default, which are included to the updating zone, is specified in the files which are located in directories, defined in *DrlDir parameters, grouped by the update type: for virus databases and the scan engine, database of web resource categories (these files are grouped according to the component which is updated—virus databases and the scan engine, the anti-spam component). Upon user request the special update zone can be created (for each update type), the server list which is specified in separate file (named custom.drl, by default), located in directory specified in *CustomDrlDir parameter. In this case, the update component will receive updates only from these servers, without using servers from the default zone.

If you do not want to use the special updating zone, clear the *CustomDrlDir value of the corresponding parameter in the component settings.

The content of the files with server lists is signed, so that the files cannot be modified. If you need to create a special list of update servers, contact technical support.

The component can back up the updated files for the next rollback of the updates, performed at user request. You can specify the location and the detail level of the backed up files in the settings. To roll back updates, use the command-line tool for Dr.Web for UNIX Mail Servers for managing the solution from the Dr.Web Ctl Dr.Web Ctl command line (it is run by drweb-ctl command).

If Dr.Web for UNIX Mail Servers is connected to the local cloud of Dr.Web for UNIX products, and it is not connected to the centralized protection server, the Dr.Web Updater component is used to synchronize updates received by cloud hosts as well, that is, it transmits updates received from update servers to the cloud, and receives updates from the cloud, which allows to reduce the total load on the Dr.Web update server. This option can be enabled or disabled in the component settings.