Page 2 of 2 FirstFirst 12
Results 11 to 13 of 13

Thread: Ping works, WWW doesn't

  1. #11
    Join Date
    Dec 2009
    Beans
    103
    Distro
    Ubuntu

    Re: Ping works, WWW doesn't

    I've actually been ruminating on this a little more, Steve, and if you look at the address that comes back, it basically looks like an empty buffer. It'd mean that linux is completing it's read from the network before the D-Link router bothers to finish writing the address it's waiting for.

    *shrug*

    There are ways into routers. Buy me a JTAG kit.
    I just need your bank account number and sort code, and we can wire you the monies directly.

  2. #12
    Join Date
    May 2007
    Location
    Basildon, England
    Beans
    339
    Distro
    Ubuntu 12.04 Precise Pangolin

    Re: Ping works, WWW doesn't

    Quote Originally Posted by changingstate View Post
    I've actually been ruminating on this a little more, Steve, and if you look at the address that comes back, it basically looks like an empty buffer. It'd mean that linux is completing it's read from the network before the D-Link router bothers to finish writing the address it's waiting for.
    Isn't there some sort of handshaking that should avoid this happening?
    Mick 'n Keef rock, Chas beats time and Ronnie is the new boy
    Registered as user 466848 with the Linux Counter. Registered Ubuntu User 22858. Our company website or our new venture

  3. #13
    Join Date
    Dec 2009
    Beans
    103
    Distro
    Ubuntu

    Re: Ping works, WWW doesn't

    Handshaking has a resource overhead and DNS was invented in 1983. I didn't get my first ZX Spectrum until 1985ish!

    I've been off reading rfc1035 : http://www.faqs.org/rfcs/rfc1035.html

    My behind has been concocting a complete fantasy, not an uncommon event. I dug this out of the section on resolvers :

    While local limits on the number of times a resolver will retransmit
    a particular query to a particular name server address are
    essential, the resolver should have a global per-request
    counter to limit work on a single request. The counter should
    be set to some initial value and decremented whenever the
    resolver performs any action (retransmission timeout,
    retransmission, etc.) If the counter passes zero, the request
    is terminated with a temporary error.
    Let's say upstream debian have built the main resolver library with low values for this counter while moblin, windows and ping are willing to implement higher values. ( I'm assuming this is a compliation time option, I've not checked the source, so if anyone has a config variable to tweak, SPEAK PLEASE ). If the DNS server on the D-Link router takes a number of operations between the values to return an answer to a query, being rather slow due to underpowered hardware or inefficient code, we might have a candidate the cause here.

    Or I might be flatulating again.

    You pays your money and takes your choice.
    Last edited by changingstate; January 13th, 2010 at 03:00 AM.
    I just need your bank account number and sort code, and we can wire you the monies directly.

Page 2 of 2 FirstFirst 12

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •