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I'm attempting to install mod_qos and I'm getting the following error when attempting to start Apache:

Starting httpd: httpd: Syntax error on line 203 of /etc/httpd/conf/httpd.conf: Cannot load /etc/httpd/modules/ into server: /etc/httpd/modules/ undefined symbol: EVP_BytesToKey

Line: 203: LoadModule qos_module modules/


[root@server]# uname -a
Linux net-kyani-n13 3.4.43-43.43.amzn1.x86_64 #1 SMP Mon May 6 18:04:41 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

Researching this issue I found a similar error here:

We do, however use mod_ssl so that module is already installed and compiled.

Any help is greatly appreciated.

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Did you compile this module yourself or is it just a binary? – Nathan C May 17 '13 at 11:41
Compiled using the apxs -i -c mod_qos.c command – Peter May 17 '13 at 11:51
This "could" be related to SSL libraries - seems odd it compiles fine if you're getting that error. I believe the package is ssl-dev or libssl-dev. It varies. – Nathan C May 17 '13 at 11:54
As hinted in the previous comments, this might be a version mismatch. Check that the module is for the exact version of apache you are running, and that the other modules in use also agree. – vonbrand May 17 '13 at 12:46

You need to make sure that mod_ssl is loaded before mod_evp in your config file.

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