Topic
5 replies Latest Post - ‏2012-02-13T12:08:17Z by SystemAdmin
Ebrahim_kh63
Ebrahim_kh63
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Pinned topic custom IHS installaton

‏2012-02-08T08:26:59Z |
How can I compile and install IHS 7 or later using custom external libraries such as pcre 7.9 and APR 1.4. pcre and APR version of default installation of IHS 7 is low and some third-party modules could not work with these libraries.
Updated on 2012-02-13T12:08:17Z at 2012-02-13T12:08:17Z by SystemAdmin
  • SystemAdmin
    SystemAdmin
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    Re: custom IHS installaton

    ‏2012-02-08T11:09:26Z  in response to Ebrahim_kh63
    You cn build apr/pcre/expat and list them in the shared library path envvar in bin/envvars above the lib/ directory, but providing your own is not something tested or recommended.

    What modules require a later pcre or APR?
    • Ebrahim_kh63
      Ebrahim_kh63
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      Re: custom IHS installaton

      ‏2012-02-12T18:23:15Z  in response to SystemAdmin
      mod_security performance depends on pcre performance. I compiled mod_security with pcre 7.9 and installed it on IHS 7 that is compiled with pcre 5. After 1 week My web server crashed. I checked http access and error logs. The only valuable logs that i could find are as below:

      notice ModSecurity: APR compiled version="1.3.8"; loaded version="1.2.12"
      warn ModSecurity: Loaded APR do not match with compiled!
      notice ModSecurity: PCRE compiled version="7.9"; loaded version="5.0 13-Sep-2004"
      warn ModSecurity: Loaded PCRE do not match with compiled!

      I have two choices: 1)compile mod_security with pcre 5 and APR 1.2.12. 2) compile IHS 7 with pcre 7.9 and APR 1.3.8. Compiling mod_security with pcre 5 is not a good choice(because of its impact on performance). I decided to compile IHS 7 with pcre 7.9 and APR 1.3.8. Is it a better choice?
      • SystemAdmin
        SystemAdmin
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        Re: custom IHS installaton

        ‏2012-02-12T19:12:27Z  in response to Ebrahim_kh63
        > Ebrahim_kh63 wrote:
        > mod_security performance depends on pcre performance. I compiled mod_security with pcre 7.9 and installed it on IHS 7 that is compiled with pcre 5. After 1 week My web server crashed. I checked http access and error logs. The only valuable logs that i could find are as below:
        >
        > notice ModSecurity: APR compiled version="1.3.8"; loaded version="1.2.12"
        > warn ModSecurity: Loaded APR do not match with compiled!
        > notice ModSecurity: PCRE compiled version="7.9"; loaded version="5.0 13-Sep-2004"
        > warn ModSecurity: Loaded PCRE do not match with compiled!

        There's no sign that this message is related to your crash.

        >
        > I have two choices: 1)compile mod_security with pcre 5 and APR 1.2.12. 2) compile IHS 7 with pcre 7.9 and APR 1.3.8. Compiling mod_security with pcre 5 is not a good choice(because of its impact on performance). I decided to compile IHS 7 with pcre 7.9 and APR 1.3.8. Is it a better choice?

        You can't choose to (re)compile IHS 7, so this is not really an option.
        • Ebrahim_kh63
          Ebrahim_kh63
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          Re: custom IHS installaton

          ‏2012-02-13T08:20:04Z  in response to SystemAdmin
          How can i solve this problem? Why IMB doesn't update its external libraries?
          • SystemAdmin
            SystemAdmin
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            Re: custom IHS installaton

            ‏2012-02-13T12:08:17Z  in response to Ebrahim_kh63
            I'm not aware of any compelling reasons to update PCRE, and this PCRE matches the one bundled with even the latest Apache 2.2.x source distributions. IBM doesn't flippantly change the bundled prerequisite utility libraries and impose unnecessary change on users.

            Can you quantify the mod_security performance regression with the old PCRE, or figure out your crash (or ??) when forcing the new PCRE to be loaded by IHS?