I use ordb.org besides sbl-xbl, there is still like spamcop, but I am quite afraid because I am running centralised servers, spamcop if one user spam the entire IP will be blocked.....so sticking to sbl-xbl and ordb.org. The combination is quite fantastic. Anyone got any other combination that would like to share?
Be careful using RBL's on CPanel boxes, you'll end up blocking clients from sending more than likely, especially the RBLs which block dynamic ranges, which kinda sucks since 80% of spam comes from those ranges too.
We went through virtually every one of the blacklists and tested them on four criteria:
1) Only blocks SINGLE IP addresses.
2) Responds fast to admin contact.
3) Has a speedy removal process.
4) Pings well from our servers.
When you are careful to use only tightly controlled (and frequently cleared) blacklists, it won't cut out nearly as much spam as the big lists, but in combination with other measures (local filters, etc.), you can do a great job reducing spam with almost no false positive blocks.
Originally posted by Allwin A Spamhaus
I don't recommend using Spamcop.net as a RBL source on hosting servers, it is an automated system that gets a LOT of false positives thanks to people reporting things like mailing lists they signed up for but can't figure out how to get off the list.
If you have any hosting clients from Mexico for example then you WILL have issues with them trying to send email to the server, or their friends trying to send to the server but finding their actual ISPs mail server is blocked. (taken from experience)
Spamhaus is good, the RBLs that block dynamic ranges are good at cutting back on the spam from trojan infected client machines. The latter will require an email server that can allow verified clients to send even if they're from a dynamic IP listed in RBLs, for what it's worth CPanel/Exim isn't one of those servers. Qmail can do it with some trickery though
Also be sure to have a whitelist if possible as you will run across times where a server is blocked at an RBL but shouldn't be, a whitelist will stop this from happening more than once.
How do you setup the RBLs, etc with cPanel, can someone share their recommendations for editing Exim from a host's perspective? I read a lot of you have specific host-related recommendations, can a host provide details on exactly what they're doing to prevent spam from being received?