About SpamDuster
What is SpamDuster?SpamDuster filters spam, viruses and phishing out of your incoming mail before it reaches any mailbox. One SpamDuster server covers the domains and email addresses of its plan (more with expansion packs), sits in front of your existing mail server, and works with cPanel & WHM, Plesk and DirectAdmin.What SpamDuster Cloud includesSpamDuster Cloud includes a dedicated filtering server run by us, spam and phishing filtering, virus scanning (on every plan except Micro), attachment and archive inspection, SPF, DKIM and DMARC checks, review and release of blocked mail, allow and block lists, log search with delivery proof, alerts and automatic updates. It filters incoming mail only.SpamDuster Cloud plans and how to chooseSpamDuster Cloud comes in seven plans, from Micro to Enterprise Plus, which differ in the size of your dedicated server and so in how much mail it handles. Prices are monthly or yearly (10 months' price for 12), slightly higher for servers in Jakarta and São Paulo, with optional backups. Each plan includes a number of domains and email addresses on one gateway (mail) server; domain expansion packs add more. Micro does not include antivirus scanning.How SpamDuster Cloud billing worksYou pay us one charge per SpamDuster Cloud server, monthly or yearly. It covers both your dedicated server on Linode and SpamDuster, so there is no cloud account or separate cloud bill. Paying yearly costs the same as 10 monthly payments. Each plan includes a number of domains and email addresses; domain expansion packs add more.What you need to use SpamDuster CloudYou need your own mail server that receives your mail, access to change your domains' DNS (MX) records, and the ability to let your mail server accept mail from the SpamDuster server. No hardware or cloud account is needed.Security and how SpamDuster handles your mailYour mail is filtered and stored on your own dedicated SpamDuster server, which no other customer shares. The server sends us health and version information, never your messages, except copies sent to the SpamDuster Cloud Scan Engine for malware scanning.SpamDuster Cloud or On-Premise?Both run the same filtering; the difference is who runs the server. Cloud includes a number of domains and email addresses per plan, with expansion packs for more; On-Premise includes unlimited domains and mailboxes on each licensed mail server with a supported control panel, with domain packs for the rest. SpamDuster Cloud, run by us on Linode, and SpamDuster On-Premise Inbound, which you run yourself, are available now; On-Premise Outbound is coming soon.SpamDuster On-Premise InboundSpamDuster On-Premise Inbound is the SpamDuster inbound filter as an appliance you install from a single ISO on your own hardware or virtualization platform, licensed per mail server with unlimited domains and mailboxes. Listings on AWS, Google Cloud and Azure Marketplace are coming soon.SpamDuster On-Premise Outbound Coming soonSpamDuster On-Premise Outbound is not available yet. It will be an appliance that filters the mail your servers send, so a compromised account or a hijacked script cannot turn your network into a spam source and get your IP addresses blocklisted.SpamDuster frequently asked questionsShort answers to the questions customers ask most about SpamDuster: what it costs, what it filters, where it runs, how setup works, and what happens to blocked mail.
Getting started
Get started with SpamDuster CloudAfter you order, we build your own SpamDuster server and email you its address and a link to set your password. You then add your mail domains, tell the filter where to deliver clean mail, send a test message, and finally point your MX records at the filter.Sign in to the SpamDuster console for the first timeOpen the set-your-password link in the "Your SpamDuster instance is ready" email, request a reset link for the username admin, choose a password, then sign in at your console address. On first sign-in the console asks you to confirm your name and set a new password before anything else.Add your mail domainsOpen Mail domains in the console, type each domain and select Add domain. SpamDuster refuses mail for any domain that is not listed, so add every domain whose mail it should filter before you change MX records.Set your destination mail serverIn Advanced, enter the host name or IP address and port of the mail server that should receive clean mail, then select Save & test. SpamDuster checks live that the server answers and will accept mail for your domain; your mail server must accept mail from the SpamDuster server's IP address.Send a test message through the filterIn Advanced, enter a mailbox on your domain under Send a test message through the filter and select Send test. One real message goes through SpamDuster to your destination server, so you can confirm delivery before you change your MX records.Point your MX records at SpamDusterAt your DNS provider, replace each domain's MX records with one MX record pointing at the Mail host (MX target) from your welcome email. Mail starts flowing through SpamDuster as the old records expire from DNS caches.
How-to guides
Review blocked mailOpen Mail in the console and pick a folder: Spam, Phishing, Viruses or Discarded hold copies of mail the filter stopped; Accepted holds copies of mail it delivered. Search by sender or subject, open a message to see why it was blocked, and release it if it was wanted.Release a blocked messageOpen the message on the Mail page of the console and select Resend to deliver it to its recipients, or Release + not spam to deliver it and teach the filter that mail like it is wanted. The console asks you to confirm before anything is delivered.Teach the filter what is spamOn the Mail page of the console, use Mark spam on spam that was delivered and Not spam on wanted mail that was blocked. SpamDuster learns from every correction. Use Report phishing and Not phishing to record phishing detection mistakes.Allow a senderIn Allowed senders, enter the sender's address or domain and the domain or mailbox it may send to, then select Allow. Its mail skips the spam and phishing checks but is still scanned for viruses and malware.Block senders and IP addressesIn Allow & block, add a sender to Blacklisted senders or an IP address to Denied connection IPs, and SpamDuster rejects their mail every time. Whitelisted IPs on the same page lets a trusted sending server bypass filtering.Find a message and prove it was deliveredUse Log search in the console to find any message by sender, recipient, subject, date or id and see what happened to it. For delivered mail it shows your mail server's reply, and you can print a delivery receipt as proof.Connect a hosting control panelIn Control Panel Integration, enable the integration, add your control panel server with the IP addresses it calls from, and paste its two one-time tokens (tenant and sync) into the panel's SpamDuster settings. The panel then keeps its domains in sync with SpamDuster automatically.Install the cPanel & WHM pluginThe SpamDuster plugin for cPanel & WHM keeps a hosting server's domains in sync with SpamDuster, keeps their mail routing right, trusts SpamDuster in the server's firewall and mail checks, and can move each domain's MX record for you. Download it from Control Panel Integration in the SpamDuster console, install it as root, then connect it under WHM > Plugins > SpamDuster with the two tokens from the console. After that it installs its own updates.Manage filtered mail in cPanelWhen your hosting provider uses the SpamDuster plugin, cPanel has a Mail Filtering page under Email. It shows the mail SpamDuster held for your domains, lets you release messages and teach the filter, and keeps your own lists of allowed and blocked senders.Change the filter's detection settingsFilter config lists the main detection checks. Set each to Block, Score or Disabled and select Save; the change applies to the live filter straight away. It also holds greylisting, blocked attachment types and phishing detection.Use your own hostname for the filterCreate a DNS A record for a name on your domain, such as mxfilter.example.com, pointing at your SpamDuster server, then enter the name under Custom hostname in Advanced and select Save. A certificate for it is requested automatically; the original hostname keeps working.Change how long mail and logs are keptMail log retention is set in Log search. Copies of blocked and delivered mail are pruned by the daily maintenance in Advanced, with a maximum age per folder. When the disk is nearly full, the oldest files are removed first.Add and manage console usersIn Users, select Add user, enter a username, email and temporary password and choose a role. Admins can disable, re-enable, reset or delete accounts; disabling an account blocks its sign-in at once.Change your password or email addressSelect your name at the top right of the console to open My profile, enter the new password or email address, enter your current password, and select Save changes.Alerts and notificationsSpamDuster watches disk space, memory, the certificate and whether the filter is running. It raises an alert when one crosses a threshold, clears it when things are normal again, and emails the first administrator on each change.Check and restart the filter's servicesServices shows each part of SpamDuster, whether it is running and how much of the server it uses, with a Restart button for the filter engine, the DNS resolver and, where your server runs one, the virus scanner. Restarting never loses mail.How SpamDuster updates itselfSpamDuster Cloud updates itself: it checks for new releases by itself and installs them, including filter engine updates. Only signed releases are installed, and a failed update is rolled back automatically.
Troubleshooting
Mail is not arriving after I changed MX recordsCheck Log search for the missing message first: it shows whether the mail reached SpamDuster and what happened to it. The usual causes are a domain missing from Mail domains, the destination mail server refusing the SpamDuster server, or DNS changes that have not spread yet.Wanted mail was blockedFind the message on the Mail page of the console, release it with Release + not spam so the filter learns, and if the sender is trusted add them under Allowed senders. Check the Filter decision on the message to see which check blocked it.Spam is getting throughMark each spam message with Mark spam on the Mail page of the console so the filter learns, block persistent senders in Allow & block, and check that every MX record points at SpamDuster so spammers cannot go around the filter.Mail from new senders is delayedWhile greylisting is on, the first message from a sender SpamDuster has not seen before can arrive a few minutes late. Later messages from that sender are not delayed. You can shorten the delay or turn greylisting off in Filter config.The destination test failsThe destination test in Advanced reports exactly where it stopped. Most failures are a firewall blocking the SpamDuster server, or a mail server that does not yet accept mail from the SpamDuster server's IP address.A released message arrives incompleteSpamDuster can only release as much of a message as it stored. If Store complete mail in Advanced keeps only the start of each message, large messages are released cut off. Raise the limit for future mail; messages already stored cannot be completed.I can't sign in to the consoleSelect Forgot password? on the sign-in page and enter your username or email; a single-use reset link is emailed to the address on your account. If no email arrives, another administrator can reset your password in Users.My SpamDuster service is suspendedWhile a SpamDuster Cloud service is suspended, incoming mail is temporarily rejected, so senders keep retrying and nothing is lost. Mail resumes automatically, with your settings intact, as soon as the account is reactivated.
Reference
The SpamDuster console, page by pageA short guide to every page of the SpamDuster console: what each one shows and what you do there, with links to the step-by-step articles.Ports and hosts to allowYour SpamDuster server receives mail on port 25 and serves the console on port 443. Your mail server must accept connections from the SpamDuster server's IP address on the port you set as the destination, usually 25.SpamDuster glossaryPlain explanations of the mail and filtering terms used in SpamDuster's console and documentation, from MX record and destination mail server to greylisting, SPF, DKIM, DMARC and phishing.