How To Block Spammers/Hackers With mod_defensible On Apache2 - php problem

Discussion in 'HOWTO-Related Questions' started by le_avion, Jul 13, 2008.

  1. le_avion

    le_avion New Member

    My server is running Ubuntu 7.10 and I ran into a problem after installing and configuring mod_defensible. The problem that I ran into is that my php pages are no longer handled by the server and instead my browser offers to download the page php source.

    In Apache's error.log I see the following which is probably related:

    apache2: udns_resolver.c:477: dns_free: Assertion `ctx != ((void *)0) && ctx != &dns_defctx' failed.
    [Sun Jul 13 12:06:00 2008] [notice] child pid 7803 exit signal Aborted (6)

    I wonder what is the reason for this problem.

    Last edited: Jul 13, 2008
  2. falko

    falko Super Moderator ISPConfig Developer

    And when you comment out the three mod_defensible directives and restart Apache, PHP works again?
  3. le_avion

    le_avion New Member

    This is correct. When I comment the lines out PHP starts working again.

  4. falko

    falko Super Moderator ISPConfig Developer

    Hm... What's in /etc/resolv.conf?
  5. le_avion

    le_avion New Member


    The first name server is my own caching name server.

  6. falko

    falko Super Moderator ISPConfig Developer

    Can you try this in the first place in /etc/resolv.conf?
  7. le_avion

    le_avion New Member

    First I would like to thank you for trying to get my issue resolved.

    This did not help but I did get it working properly now. Seems that the version of mod_defensible in Ubuntu 7.10 has a bug. I found a reference to the same problem I am having in a Debian bug report. I ended up installing the newer libudns0 and mod_defensible from Hardy (Ubuntu 8.04) and that fixed the problem. I will file a bug report with Ubuntu and ask them to back port it to 7.10 since it is still a supported version. From the Debian bug report:

    libapache2-mod-defenisble has a serious issue involving dns resolution in
    the testing tree. Anytime you activate and use the module the following
    critical error is thrown by Apache:

    [Mon Sep 17 10:48:25 2007] [notice] child pid 30877 exit signal Aborted (6)

    apache2: udns_resolver.c:477: dns_free: Assertion `ctx != ((void *)0) && ctx
    != &dns_defctx' failed.

    This is a blocker issue that prevents Apache from serving any requests while
    the module is activated.

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