7 E-mail security begins at the gateway by controlling all incoming and
8 outgoing e-mail messages. {pmg} addresses the full spectrum of
9 unwanted e-mail traffic, focusing spam and virus detection. {pmg}
10 provides a powerful and affordable server solution to eliminate spam,
11 viruses and blocking undesirable content from your e-mail system. All
12 products are self-installing and can be used without deep knowledge of
15 image::images/Proxmox-Mailprocessing.png[]
23 {pmg} uses a wide variety of local and network tests to identify spam
24 mail. Here is a short list of used filtering methods:
26 Receiver Verification::
28 Many of the junk messages reaching your network are emails to
29 non-existent useres. Proxmox Mail Gateway detects these emails on SMTP
30 level, which means before they are transferred to your networks. This
31 reduces the traffic to be analyzed for spam and viruses up to 90% and
32 reduces the working load on your mail servers and scanners.
34 Sender policy framework (SPF)::
36 Sender Policy Framework (SPF) is an open standard for validating
37 emails and to prevent sender IP address forgery. SPF allows the
38 administrator of an Internet domain to specify which computers are
39 authorized to send emails with a given domain by creating a specific
40 SPF record in the Domain Name System (DNS).
42 DNS-based Blackhole List::
44 A DNS-based Blackhole List (DNSBL) is a means by which an Internet
45 site may publish a list of IP addresses, in a format which can be
46 easily queried by computer programs on the internet. The technology is
47 built on top of the Domain Name System. DNSBLs are used to publish
48 lists of addresses linked to spamming.
52 Exclude senders from SMTP blocking. To prevent all SMTP checks
53 (Greylisting, Receiver Verification, SPF and RBL) and accept all
54 e-mails for the analysis in the filter rule system, you can add the
55 following to this list: Domains (Sender/Receiver), Mail address
56 (Sender/Receiver), Regular Expression (Sender/Receiver), IP address
57 (Sender), IP network (Sender)
59 Bayesian Filter - Automatically trained statistical filters::
61 Some particular words have a higher probability of occurring in spam
62 emails rather than in legitimate emails. By beeing trained to
63 recognize those words, the Bayesian checks every email and adjusts the
64 probabilities of it beeing a spam word or not in its database. This is
67 Black- and Whitelists::
69 Black- and Whitelists are an access control mechanism to accept,
70 block, or quarantine emails to recipients. This allows you to tune the
71 rule-system by applying different objects like domains, email address,
72 regular expression, IP Network, LDAP Group, and others.
74 Autolearning algorithm::
76 Proxmox Mail Gateway gathers statistical information about spam
77 emails. This information is used by an autolearning algorithm, so the
78 system becomes smarter over time.
80 Spam Uri Realtime BlockList (SURBL)::
82 SURBLs are used to detect spam based on message body URIs (usually web
83 sites). This makes them different from most other Real-time
84 Blocklists, because SURBLs are not used to block spam senders. SURBLs
85 allow you to block messages that have spam hosts which are mentioned
90 Greylisting an email from a sender your system does not recognize,
91 means, that it will be temporarily rejected. Since temporary failures
92 are built into the RFC specifications for mail delivery, a legitimate
93 server will try to resend the email later on. This is an effective
94 method because spammers do not queue and reattempt mail delivery as is
95 normal for a regular Mail Transport Agent.
97 Greylisting can reduce e-mail traffic up to 50%. A greylisted email
98 never reaches your mail server and thus your mail server will not send
99 useless "Non Delivery Reports" to spammers.
101 SMTP Protocol Tests::
103 {postfix} is able to do some sophisticated SMTP protocol tests (see
104 `man postscreen`). Most spam is sent out by zombies (malware on
105 compromised end-user computers), and those zombies often try to
106 maximize the amount of mails delivered. In order to do that, many of
107 them violates the SMTP protocol specification and can thus be detected
114 {pmg} integrates {clamav}, which is an open-source (GPL) antivirus
115 engine designed for detecting trojans, viruses, malware and other
118 It provides a high performance mutli-threaded scanning daemon, command
119 line utilities for on demand file scanning, and an intelligent tool
120 for automatic signature updates.
123 Object-Oriented Rule System
124 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
126 The object-oriented rule system enables custom rules for your
127 domains. It’s an easy but very powerful way to define filter rules by
128 user, domains, time frame, content type and resulting action. {pmg}
129 offers a lot of powerful objects to configure your own custom system.
133 Defines the final actions.
137 Who is the sender or receiver of the e-mail?
141 What is in the e-mail?
145 When is the e-mail received by Proxmox Mail Gateway?
147 Every rule has five categories FROM, TO, WHEN, WHAT and ACTION. Every
148 of these categories can contain several objects and a direction (in,
151 Options range from simple spam and virus filter setups to
152 sophisticated, highly customized configurations blocking certain types
153 of e-mails and generating notifications.
159 Identified Spam mails can be stored to the user accessible Spam
160 quarantine. Thus users can view and manage there Spam mails by
167 The innovative Proxmox Message Tracking Center tracks and summarizes
168 all available logs. With the web-based and user friendly management
169 interface, the IT admins can easily overview and controll all
170 functions from a single screen.
172 The Message Tracking Center is very fast and powerful, tested on {pmg}
173 sites processing over a million emails per day. All different log
174 files from the last 7 days can be queried and the results are
175 summarized by an intelligent algorithm.
177 - Arrival of the email
178 - Proxmox filtering processing with results
179 - Internal queue to your email server
180 - Status of final delivery
183 High Availability with Proxmox HA Cluster
184 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
186 To provide a 100% secure email system for your business, we developed
187 Proxmox High Availability (HA) Cluster. The Proxmox HA Cluster uses a
188 unique application level clustering scheme, which provides extremely
189 good performance. Fast set-up within minutes and a simple, intuitive
190 management keep resource needs low. After temporary failures, nodes
191 automatically reintegrate without any operator interaction.
196 It is possible to query user and group data from LDAP servers. This
197 may be used to build special filter rules, or just to provide
198 authentication services for the Spam quarantine GUI.
201 Fetchmail integration
202 ~~~~~~~~~~~~~~~~~~~~~
204 {pmg} allows you to fetch mail from other IMAP od POP3 servers.
207 Flexible User Management
208 ~~~~~~~~~~~~~~~~~~~~~~~~
210 The administration interface uses a role based access control scheme,
211 using the following roles:
215 This role is allowed to do everything (reserved for user 'root').
219 Full access to mail filter setup, but not allowed to change network setup.
223 Is able to view and manage the Spam Quarantine.
227 Has read-only access to the whole configuration, can access logs and
231 Your benefit with {pmg}
232 -----------------------
234 * Open source software
237 * Fast installation and easy-to-use
238 * Web-based management interface
240 * Huge active community
241 * Low administration costs and simple deployment
244 include::getting-help.adoc[]