Data is protected from viruses by a scanning service, vscan, that uses various scan engines. A scan engine is a third-party application, residing on an external host, that examines a file for known viruses. A file is a candidate for virus scanning if the file system supports the vscan service, the service has been enabled, and the type of file has not been exempted. The virus scan is then performed on a file during open and close operations if the file has not been scanned with the current virus definitions previously or if the file has been modified since it was last scanned.
The vscan service can be configured to use multiple scan engines. Best practice is to use a minimum of two scan engines. The requests for virus scans are distributed among all available scan engines.
The vscanadm show command lists scan engines configured on the system.
# vscanadm show max-size=1GB max-size-action=allow types=+* no scan engines configured