Re: Old TCP connections after IP address change

From: Mario Moder (evilspam_at_usenet.arcornews.de)
Date: 06/11/05

  • Next message: Floyd L. Davidson: "Re: DIY WiFi antenna (to increase reception)" 
    Date: 11 Jun 2005 18:07:52 GMT

    Clifford Kite wrote:
    > the function not the script). I pointed him to keepalive_* files in
    > /proc, which I've since come to realize won't do any good unless his
    > applications can enable TCP keepalive probes and TCP on the server
    > end implements keepalive code.

    After reading the spare information [1] about these files, I agree
    with you. After all, I do also think the linux networking and tcp/ip
    settings need no change, although it's good to know that some settings
    _can_ be tweaked for special cases. I don't consider my problem a
    special case because I guess there are many DSL users with dynamic IP
    address assignment and forced 24h-disconnect by the provider, at least
    in Germany.

    Since there was missing information from my side, I want to fill this
    gap: My ADSL modem is connected through eth0 and I use pppd on my
    linux box to establish the PPPoE connection. No router or firewall in
    between.

    > I'll offer a couple more suggestions for the OP to consider and then
    > I'm outta here.

    Thank you ;-)

    > A script that tests for a change of IP address and sends a SIGTERM
    > signal to all running applications with TCP connections when there
    > is a change might work, depending on how the applications react

    That's the idea that was first in my mind because I already know
    applications which do indeed react in such way when receiving a
    SIGTERM or SIGHUP signal. I also know apps which do check for server
    connection every minute.

    Conclusion from my side: If an application needs 20 minutes to realize
    that the server is not responding on a certain TCP connection, it's
    not the networks fault.

    > to SIGTERM. You also might (no guarantee) get a better answer by
    > posting on comp.protocols.tcp-ip.

    Uhh! The guys there will raise a sunken smile if I tell them to change
    the TCP/IP protocol because some apps don't react on IP address change
    ;-)

    Seriously, I will look what I can do at the application level before I
    ask there about the best tcp/ip settings for my case.

    Thanks for your replies.

    Mario

    [1] http://ipsysctl-tutorial.frozentux.net/chunkyhtml/index.html 

    -- 
http://oddfellow.endofinternet.org/
  • Next message: Floyd L. Davidson: "Re: DIY WiFi antenna (to increase reception)"

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