whitelisting

Fred Krogh · Posted: Mon Apr 25, 2016 10:23 pm Post subject: whitelisting

Without knowing what I'm doing I've collected a bunch of email addresses that I thought I would put in a whitelist. I started to use these with sqlgrey and discovered that you can only use domain names there. I see that amavisd will allow email addresses in a whitelist, but I'm not clear on when things get done. When I go on vacation I like to forward mail to gmail so I can read mail from a browser. But I don't want all my spam to go to my gmail account (google complains). I'm concerned that I have conflicting desires.

1. Mail from my known senders comes through all the time and quickly and is not using greylisting.
2. Other mail uses greylisting.
3. The vast majority of spam will get blocked both from my mail server and when forwarded to gmail.

If this is not possible, is greylisting going to impact mail that currently is received with no problems?
Many thanks,
Fred

NeddySeagoon · Posted: Mon Apr 25, 2016 10:54 pm Post subject:

Fred Krogh,

I use Spamdyke in front of qmail. Everything gets greylisted.
The only problem I've hand is with Mercedes-Benz. That wasn't greylisting, it was reverse DNS lookups.

I also use a Real Time Blackhole service and reverse DNS, along with greylisting

The greylist delay seems to be minimal but its not something you can control, unless you refuse a message for a set time.
Its up to the sender when they retry.
From my logs, spammers never retry. I have the greylist duration minimised.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

Fred Krogh · Posted: Mon Apr 25, 2016 11:17 pm Post subject:

Sorry, I should have mentioned that I'm using postfix (and amavisd and clamd). Does your solution work with postfix. I'm not clear on how one would get something "in front of it". Thanks.

NeddySeagoon · Posted: Tue Apr 26, 2016 4:22 pm Post subject:

Fred Krogh,

Spamdyke is a qmail preprocessor. To incoming emails, it looks like qmail. However, messages are only actually passed to qmail once the spam checks have passed. It probably won't work with other mail programs but I've not tried.

The main thing I was trying to say in that greylisting appears to be harmless and I accept immediate retries.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

cboldt · Veteran Joined: 24 Aug 2005 Posts: 1046

I whitelist using procmail, which is AFTER your MTA (postfix, exim, qmail, etc.).

You can use procmail to copy and forward mail to another address, such as your gmail.com address; but I wonder how you get your mail now. I use fetchmail to fetch from gmail.com and assorted other sources and place that collection on my local server (after sorting the incoming with procmail). My local server is also running dovecot, so I can read mail on my local server, from remote.

I'm not advocating you run your system like that, just saying that resolving your question can involve the entierty of the scheme that you use to collect/receive email. Procmail can be used to sort incoming at your local end, no matter what.