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Check for broken RBLs ?

I

idomain.dk

Guest
Hi,

I've tried searching this, but haven't quite found what i was looking for.

Since Plesk (atleast 8.4) sometimes has problems, if using RBLs and one of these are "broken" - QMail stops, and cannot be startet through Plesk, however it seems SMTP DOES respond, but quite slowly.

At first, I wrote a small script, which does a simple host lookup on each RBL, and if they don't resolve to an IP address, the "broken" RBL is removed from the list, so the QMail service can start again.

I'm not sure, if this is the proper way to test if an actual RBL works or not, and after a bit of digging, I found this old post:
http://forum.swsoft.com/showpost.php?p=206592&postcount=11

So my question is, if it's a more proper procedure, to do a host lookup on:
2.0.0.127.list-name e.g. 2.0.0.127.zen.spamhaus.org

I tried this, and "host 2.0.0.127.zen.spamhaus.org" returns "127.0.0.2" where a standard "host zen.spamhaus.org" does return anything.

Here's an output from my new script, which uses the technique above:
Code:
zen.spamhaus.org = 127.0.0.2, OK
dnsbl.njabl.org = 127.0.0.2, OK
dnsbl.sorbs.net = 127.0.0.10, OK
bl.spamcop.net = 127.0.0.2, OK
list.dsbl.org = 127.0.0.2, OK
multihop.dsbl.org = 127.0.0.2, OK
unconfirmed.dsbl.org = 127.0.0.2, OK
combined.rbl.msrbl.net = 127.1.0.2, OK
spamsources.fabel.dk = 127.0.0.2, OK
rbl.some-bogus-host.tld = 127.0.0.1, BAD

It's a PHP script, which uses gethostbyname() and if the host resolves to the same hostname as the input, or 127.0.0.1
it is marked as BAD, and otherwise OK

As you can see, some of the lists returns another result, than the testet 127.0.0.2 address (e.g. dnsbl.sorbs.net, 127.0.0.10) and I kinda thought the query should return 127.0.0.2 in all cases.

The main reason for this script, is to get rid of this issue, of having QMail SMTP crash if a bad RBL is encountered, so my thoughts where to either periodically check a list of RBLs and weed out the broken ones (might create a lot of unnecessary traffic though) OR write the above into the Watchdog module, which can monitor, and restart QMail.

Thanks.
 
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