the –dump-mesg facility does not work. There is a fix available in community. This is it : [PATCH] --dump-dmesg fix for post 3.5 kernels. This patch enable the --dump-dmesg functionality that was broken with post 3.5 kernel which use the variable-length record format for the kernel log buffer. http://sourceforge.net/p/makedumpfile/code/ci/36c24587df3f0aea902b3309d1d72ade0edb77b2/
please apply http://sourceforge.net/p/makedumpfile/code/ci/36c24587df3f0aea902b3309d1d72ade0edb77b2/ on our makedumpfile package.