Ricardo Kleemann <[EMAIL PROTECTED]> wrote: > I'm trying to understand how the RBL checking is working... > I have it setup to check spamcop, using bl.spamcop.net, but > it seems to me bl.spamcop.net doesn't resolve in DNS? > > I've tried using dig and nslookup to resolve the IP for > bl.spamcop.net and come up empty. So how does it seem to > work with the RBL checker in courier?
As with all DNS blacklists, the blacklist name (here 'bl.spamcop.net') is a DNS zone name, not a host name. Host names resolve as "A" records in the DNS, while zone names resolve as "NS" (and sometimes "SOA") records in the DNS. A DNS name may be a host name *and* a zone name, e.g. 'spamcop.net': $ dig +noall +answer spamcop.net A spamcop.net. 12 IN A 80.15.236.150 spamcop.net. 12 IN A 80.15.236.231 $ dig +noall +answer spamcop.net NS spamcop.net. 1811 IN NS ns1-93.akam.net. spamcop.net. 1811 IN NS ns1-109.akam.net. spamcop.net. 1811 IN NS ns1-117.akam.net. ... A zone name's NS records specify which DNS servers should be asked for names (host, zone, whatever) in that zone. That is, for names in the 'bl.spamcop.net' zone (e.g. '225.85.30.195.bl.spamcop.net', for the IP address 195.30.85.225), these DNS servers are responsible: $ dig +noall +answer bl.spamcop.net NS bl.spamcop.net. 1667 IN NS blns6.spamcop.net. bl.spamcop.net. 1667 IN NS blns8.spamcop.net. bl.spamcop.net. 1667 IN NS blns9.spamcop.net. ... To check whether an IP address is listed on a certain DNS blacklist, look up the "A" record(s) in the blacklist's zone like this: $ dig +noall +answer 225.85.30.195.bl.spamcop.net A There's no A record for '225.85.30.195.bl.spamcop.net', thus the IP address 195.30.85.225 is not listed on the blacklist. ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. Does SourceForge.net help you be more productive? Does it help you create better code? SHARE THE LOVE, and help us help YOU! Click Here: http://sourceforge.net/donate/ _______________________________________________ courier-users mailing list [EMAIL PROTECTED] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
