TL;DR: I want to pull emails from 5 accounts on to my homeserver to anti spam them and have my clients pull from there
I currently have like 5 major email accounts on different providers which I use for 100s of accounts on many platforms.
Some of these accounts are very old and come with the added bonus of no spam filter on the free tier.
Now, if you use outlook, you can define anti spam rules there, I know. But since I‘m using many different devices and different mail clients, I can’t be bothered to make anti spam rules for all of them.
So I thought it should be doable to pull all the emails from all my accounts and have them go through anti spam on my home server. Sidenote: I have anti spam on some email providers but I can’t redirect the one address to there as to use that accounts anti spam.
One solution would be to just get rid of this one account but I‘m a little anxious about the consequences since it is my oldest account with unthinkable amounts of accounts linked to it.
Does anyone have a similar scenario or an idea for a solution?
My advice - do not fall into the trap that you can run e-mail better than a provider who does that for a living.
The easiest way imo is to pick a provider who specializes in this sort of thing. Then begin to rotate your accounts from the old account to the new one, utilizing aliases or masks as needed and desired.
as you do so , archive old emails off your old account. Periodically check but remove it from your daily driver. At some point, all will be left is spam at which point you can … let that mail provider manage for you.
Many mail providers have excellent spam protection so you are right - get it at the source.
Depends how much your time is worth? For some it is easily worth the $1-$5/USD Month to let your mail provider handle the bulk of it.
I might be wrong, but for me OP is not trying to actually run email, rather have a staging ground that pulls all emails from their accounts on actual providers, apply some treatment to said emails and pull them from client-side apps on their devices.
Yeah I get that, but the way that usually works is by running a mail host that relays to upstream accounts.
Such things are a stairway to heaven to malware & Trojan horses…nothing says “check me out” like a bot finding out smtp is open on a local domain behind a firewall. That moves the attack from auto crypto mal to “how can we control this dudes email”.
I get the intention just be very very careful.
Dovecot + Postfix + Rspamd can do it. Instead of pulling emails you can simply forward those providers to your homeserver account. You may also setup Postfix in a way that would allow you to use our @gmail @hotmail addresses as “from” addresses / aliases to your local account and it will automatically submit the email through the provider SMTP server when you send something.
If you really want to pull email instead of setting up forwards (have your server offline more time and whatnot) there are a few options:
- https://www.fetchmail.info/ - the classic tool for the job
- https://github.com/getmail6/getmail6 - another classic solution
- https://github.com/mback2k/go-getmail - probably what I would use today
To route the outgoing email through the right provider / external SMTP server based on the “from” address you may configured it like this:
smtp_sasl_auth_enable = yes smtp_sender_dependent_authentication = yes smtp_sasl_password_maps = mysql:/etc/postfix/virtual/mysql-external-alias-credentials.cf sender_dependent_relayhost_maps = mysql:/etc/postfix/virtual/mysql-external-alias-relay-hosts.cf smtp_sasl_security_options = noanonymousmysql-external-alias-credentials.cf:
user = XXXXX password = XXXXXX hosts = 127.0.0.1 dbname = mailserver query = SELECT concat(relay_user, ':', relay_passwd) AS credential FROM `Virtual_Alias_External` WHERE alias='%s' AND active = 1;mysql-external-alias-relay-hosts.cf:
user = XXXXX password = XXXXXX hosts = 127.0.0.1 dbname = mailserver query = SELECT relay_host AS transport FROM `Virtual_Alias_External` WHERE alias='%s' AND active = 1;MySQL table structure:
CREATE TABLE `Virtual_Alias_External` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `alias` varchar(70) NOT NULL, `owner` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL, `active` tinyint(1) NOT NULL DEFAULT 0, `relay_host` varchar(70) NOT NULL DEFAULT '', `relay_user` varchar(70) NOT NULL, `relay_passwd` varchar(70) NOT NULL, PRIMARY KEY (`id`) USING BTREE ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci ROW_FORMAT=COMPACT;Create an entry like this:
alias: [email protected] owner: [email protected] active: 1 relay_host: [smtp.gmail.com]:587 relay_user: [email protected] relay_passwd: your-gmail-password-or-app-passwordNow when you send and email and the
fromis set asyour-emai@gmail.comPostfix will route the email through Gmail’s SMTP server with credential stored on that table. If done correctly (smtpd_sasl_authenticated_header = no) no references tolocal-email-address@homeserver.example.orgwill show up on the email headers.Wow! Thanks for elaborating! I‘ll look into this! Looks like a ton of useful advice.
