Search Again: Semi-ot, local DNS lookups From: Scott Haneda Date: Monday, September 20, 2004 Time: 7:59:48 pm Please bare with me on this one... I am processing credit card requests against authorzenet.com, the specific address I SSL post to is secure.authorize.net In short, I call curl from php and send off some data to secure.authorize.net, this has always worked just fine in the past. As of recent, secure.authorize.net was a targert of a DDoS attack, I am getting errors when posting to that address, here is where it gets strange... I can load the url <https://secure.authorize.net/> on any machine just fine. The machine that I run curl on does not have QDNS installed on it, that is on a separate machine, same subnet, so: Curl machine -> IP of remote QDNS server listed in TCP/IP QDNS machine -> normal install of QDNS What I am finding is that if I do a lookup on secure.authorize.net I get back: secure.authorize.net. 174 IN A 64.94.118.66 If I take 64.94.118.66 and use that IP to tell curl to post to, it works reliably, if I use the DNS hostname, it works sporadically. I suspect that as a result of the DDoS attack, they changed IP addresses or something, at any rate, I must be arriving at the wrong machine. The hard coded IP address always works. I can alter my scripts to use that, but then I have to babysit their DNS records in the event they change the IP address. My question is, is there any way on the curl machine to watch the resolution of the domain name to A record and see what IP address it is getting back, then maybe I can better track this down. Perhaps there is a way to tell the local resolver to always check for a fresh record for this one domain? Another strange thing is it seems if I reboot the curl machine, it gets it right for a few hours, then it fails a bit and works a bit, I just can not get it to work all the time like it used to. Of course, ssh'ing into the curl machine and doing a dig on the domain shows me the IP address that works, and this is even when I am not able to process a credit card transaction due to a connection failure. -- ------------------------------------------------------------- Scott Haneda Tel: 415.898.2602 <http://www.newgeo.com> Fax: 313.557.5052 <scott@newgeo.com> Novato, CA U.S.A.

Messages In This Thread: Semi-ot, local DNS lookups by Scott Haneda on Sep 20, 2004 at 7:59:48 pm Re: Semi-ot, local DNS lookups by Men & Mice Support on Sep 21, 2004 at 2:37:46 pm Re: Semi-ot, local DNS lookups by Steve Fabian on Sep 21, 2004 at 2:45:06 pm Re: Semi-ot, local DNS lookups by Scott Haneda on Sep 22, 2004 at 5:08:50 pm Re: Semi-ot, local DNS lookups by Men & Mice Support on Sep 22, 2004 at 5:24:38 pm Re: Semi-ot, local DNS lookups by Scott Haneda on Sep 22, 2004 at 6:10:58 pm Re: Semi-ot, local DNS lookups by Scott Haneda on Sep 22, 2004 at 6:21:33 pm Re: Semi-ot, local DNS lookups by Men & Mice Support on Sep 22, 2004 at 6:36:28 pm Re: Semi-ot, local DNS lookups by Cayce Will on Sep 23, 2004 at 11:43:47 am Re: Semi-ot, local DNS lookups by Scott Haneda on Sep 23, 2004 at 1:09:54 pm Re: Semi-ot, local DNS lookups by Ken Eddings on Sep 23, 2004 at 2:13:16 pm