[Crash-utility] How does crash find booted kernel?

Hi all, I am trying to use crash on RHEL 7.0.After executing "crash" command, it outputs: crash: cannot find booted kernel -- please enter namelist argument After referring to crash white paper (https://people.redhat.com/anderson/crash_whitepaper/), I know it needs vmlinux file. So I install "kernel-debuginfo" package: [root@localhost boot]# rpm -ql kernel-debuginfo | grep vmlinux /usr/lib/debug/lib/modules/3.10.0-123.el7.x86_64/vmlinux Then execute crash, it still prompts the same error: crash: cannot find booted kernel -- please enter namelist argument I try to copy vmlinux file into /boot directory, but this error still exists. How can I fix this issue? Thanks very much in advance! Best Regards Nan Xiao