F-Secure Internet Gatekeeper for Linux/Administrator’s Guide
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10.4
Scanning Viruses Before Saving Mail to the Mail Server
By default, virus scans are performed on all inbound e-mails that are sent to the mail server by using
the specified POP protocol. For this reason, you do not need to make any changes to the mail server.
It is also possible to check inbound e-mails in SMTP before they are saved to the mail server.
The following example uses a single F-Secure Internet Gatekeeper for Linux server to check both
outbound and inbound e-mails for viruses.
Overview of operations:
•
Without virus scanning
If F-Secure Internet Gatekeeper for Linux is not implemented, outbound e-mails are transferred
through an internal mail server to the destination mail server. Inbound e-mails are stored in an
internal mail server, and users can retrieve them by using the POP protocol.
•
With virus scanning
If F-Secure Internet Gatekeeper for Linux is implemented, the product scans outbound e-mails for
viruses. After that the e-mails are delivered to the destination mail server by using the internal mail
server. After the product has scanned inbound e-mails for viruses, the e-mails are stored on an
internal mail server. Users can retrieve them by using the POP protocol. In addition, restrictions
are applied to outbound e-mails to prevent open relays (third-party relays) and e-mail abuse.
Setting Example
Internal mail server (mx)
External mail server
Client
F-Secure Internet
Gatekeeper for
Linux (mx)
Internal mail server
(mx2)
Client
POP
SM TP
SM TP
SM TP
SM TP
SM TP
SM TP
POP
M ail received
M ail sent
External mail server
M ail received
M ail sent
Without virus scanning
With virus scanning