npsimons's Journal: SORBS DUHL Invalid (and other problems)

I have a problem: my email servers are listed as having dynamic IP addresses in SORBS. Normally, this wouldn't be a problem as only incompetent email administrators would use a DUHL, much less SORBS's DUHL, to automatically bounce email. As evidenced by comments in a previous slashdot story, SORBS is not only often wrong, but appears to be a racketeering organization in the "pay us money to get off our lists" sense.

Every once and a while, I see a message in the logs saying something similar to "550: dynamic IP address blocked - see http://www.sorbs.net/lookup.shtml?${MY_EMAIL_SERVER_IP_ADDRESS}". It used to be I would do a "sudo iptables --insert INPUT --source ${IP_ADDRESS_OF_BROKEN_SERVER} --jump DROP". I've stopped doing that as I realize it's counterproductive and will prevent the people who need to see the notice about the listing from seeing it. I've also tried going to the SORBS website to get delisted, but I've never received a response, and I find it kind of funny that the netblock my IP address is in was delisted, then relisted a second later.

All of this didn't matter much as most of the time the email servers that were blocking me were ones I never sent email to and were just getting double bounces from the Joe Job that is still going on against my domain name. Side note: ironic that the exact same servers that block me can't even be arsed to check the SPF records in my DNS server to make sure they won't try to bounce a message to an address that doesn't exist.

However, I have recently been getting bounces from Mediacom's email servers, which is a problem because I do want to send email to a couple of friends who have @mchsi.com addresses. I'm not sure why I've been blocked; the error message is a fairly generic "550 Blocked for abuse. Please contact the administrator of your ISP or sending mailservice.". As I don't allow SPAM to be sent from my mail server (to the best of my knowledge), I have no idea what "abuse" they may be talking about. I suspect that they are using SORBS DUHL, as my mail servers are not listed in any other blacklists (that I know of).

I've tried sending email to [e-mail]. When that bounced, I tried to send email to [e-mail]. Of course that bounced too. Doing a whois, I find that I should email [e-mail] as the technical and admin contact, but that email address is over quota. Next I try to call the (long distance) phone number, only to have to leave a message. I try calling again, but this time asking for the email administrator instead of the name listed in whois. I have to leave another message.

So what should I do now? I'm kind of stuck, and the idea of telling my friends who use mchsi.com email addresses that they should get another is kind of ridiculous (after all, I got my own domain name so I would never have to change email addresses again). I'm considering the following options:

• Faxing the fax number in the whois database listing for mchsi.com
• Posting to NANAE to show good faith that I don't want to spam and I'm looking for help, and will do what it takes to get off RBLs.
• Calling the support number for Mediacom and telling them that they are blocking legitimate email to their customers.

Anyone else have any ideas?