On Apr 5, 2009, at 2:53 AM, Paweł Leśniak wrote:
A bit different situation is with spamcannibal. It's "normal" RBL,
but in my place it was giving 10 to 50 false positives daily. A
month ago spamcannibal was stopping some backscatter. Now I get
rarely any hits, but it's used as the very last RBL to check emails
from <> ans postmaster. Soem citation from their site:
Agree with your both of your comments but in the interest of brevity
only quoted the above. One has to be super careful in checking against
RBLs - understand their criteria! I've ended up doing three:
1) Barracuda's BRBL http://www.barracudanetworks.com/ns/news_and_events/index.php?nid=305
- This is fantastic, and as a Barracuda customer I've always had
access to it - it's now free.
2) Spamcop.net
3) Spamhaus
Another thing to watch for is if your particular RBL has a blacklist
of dynamic IP addresses, that you either disable deep header scanning,
or disable it just for that one RBL. It's one thing to refuse mail
from hosts whose reverse DNS points to
254.1.168.192.dynamic.adsl.bellsouth.net, but if you are scanning all
headers, you might find an address like that from somebody who
legitimately sends mail through their from a mail client.
Backscatter looks very interesting, though, I was not aware of it and
will check into it immediately.
