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Beware of Using Google Or OpenDNS For iTunes

Relayman writes "Joe Mailer wanted to download an iTunes movie recently and his Apple TV told him it would take two hours. When he switched his DNS resolver settings, the download time dropped to less than 20 seconds. Apparently, iTunes content is served by Akamai which uses geolocation based on the IP address of the DNS request to determine which server should provide his content. When you use Google or OpenDNS to resolve the Apple domain name, all the requests to Akamai appear to be coming from the same location and they're all directed to the same server pool, overloading that pool and causing the slow downloads. The solution: be wary of using Google or OpenDNS when downloading iTunes files or similar large files. Use your own ISP's DNS servers instead or run your own resolving DNS server."

7 of 348 comments (clear)

  1. Namebench DNS tool by maggotbrain_777 · · Score: 5, Interesting

    This afternoon, I found a tool from Google Code called namebench which tests response times against multiple DNS servers and give recommendations based upon a number of query types. The results returned when checking the 'censorship tests' were interesting. Seems a number of sites (wikileaks, isohunt, stormfront) returned 'incorrect' results across DNS servers. I'm going to try this over the next couple of days and see if any of my browsing speeds improves.

  2. Multiple DNS feature? by Anonymous Coward · · Score: 2, Interesting

    Seems like it would be useful to use multiple DNS servers and then choose whichever one has the fastest download and abandon the other connections.

    Do any browsers/OSs/whatever have this feature? As I understand it, the secondary DNS feature only uses the secondary server when the primary server is down.

  3. Re:And how is this news? by xnpu · · Score: 4, Interesting

    BTW - Remember when Google proposed to modify the DNS protocol to pass on the end-users IP? This is exactly why.

  4. Re:Good advice - Always use your ISP for DNS by Z00L00K · · Score: 3, Interesting

    I already do, and since my ISP censors the internet through their DNS there is no alternative to go back to them.

    And a cleaned up version of my config. It doesn't involve the ISP at all but queries the root servers on the net instead.

    And as long as the ISP:s doesn't filter the DNS requests to the root servers this is the way to go right now.


    options {
                    allow-query {
                                    127.0.0.1;
                                    192.168.0.0/16;
                    };
                    directory "/var/named";
                    pid-file "/var/run/named/named.pid";
                    recursion yes;
                    dnssec-validation no;
    };

    key mykey. {
                    algorithm HMAC-MD5;
                    secret "** Secretas... ***";
    };

    zone "." {
                    type hint;
                    file "root.hints";
    };

    zone "int.anon.org" {
                    type master;
                    allow-update { key mykey.;};
                    file "int.anon.org.db";
                    notify yes;
    };

    zone "1.168.192.in-addr.arpa" {
                    type master;
                    allow-update { key mykey.;};
                    file "1.168.192.db";
                    notify yes;
    };

    zone "localdomain" {
                    type master;
                    file "localhost.db";
                    notify no;
    };

    zone "0.0.127.in-addr.arpa" {
                    type master;
                    file "0.0.127.db";
    };

    zone "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa" IN {
                    type master;
                    file "ip6.local.db";
                    allow-update { none; };
    };

    --
    If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
  5. Re:Good advice - Always use your ISP for DNS by hazem · · Score: 4, Interesting

    Use your own ISP for DNS.

    Do you have any tips for keeping your ISP from directing a "server not found" to one of their crappy ad-ridden search pages? I think that's a major reason people choose DNS servers that aren't at their ISP.

  6. Re:Good advice - Always use your ISP for DNS by Khyber · · Score: 3, Interesting

    It's blacklisted in my router at the root domain level.

    Slashdot runs so much faster, now.

    WHY MUST YOU LOAD SOMETHING WHEN I'M CLOSING YOUR TAB, SLASHDOT?

    Seriously, that's a bunch of bullshit.

    --
    Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
  7. Re:Good advice - Always use your ISP for DNS by nabsltd · · Score: 3, Interesting

    Sure you can, Primary and secondary are setup to openDNS on my router...

    I really don't understand why such a high percentage of /. readers use anything other than their own DNS server (i.e., a DNS server in or behind their router).

    It's insanely trivial to install a caching DNS resolver on just about any OS and there is also custom router firmware that does this.