<div dir="ltr">On 2 November 2015 at 09:09, Nan Xiao <<a href="mailto:xiaonan830818@gmail.com" target="_blank">xiaonan830818@gmail.com</a>> wrote: <div class="gmail_extra"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">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 (<a href="https://people.redhat.com/anderson/crash_whitepaper/" rel="noreferrer" target="_blank">https://people.redhat.com/anderson/crash_whitepaper/</a>), 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 -- Crash-utility mailing list <a href="mailto:Crash-utility@redhat.com">Crash-utility@redhat.com</a> <a href="https://www.redhat.com/mailman/listinfo/crash-utility" rel="noreferrer" target="_blank">https://www.redhat.com/mailman/listinfo/crash-utility</a> </blockquote></div> Hi Nan, You need to make sure that the version of kernel-debuginfo package must match with the version of running kernel. Eg: # rpm -q kernel kernel-3.10.0-229.el7.x86_64 # uname -r 3.10.0-229.el7.x86_64 # rpm -q kernel-debuginfo package kernel-debuginfo is not installed # rpm -ivh kernel-debuginfo-common-x86_64-3.10.0-229.el7.x86_64.rpm Preparing... ################################# [100%] Updating / installing... 1:kernel-debuginfo-common-x86_64-3.################################# [100%] # rpm -ivh kernel-debuginfo-3.10.0-229.el7.x86_64.rpm Preparing... ################################# [100%] Updating / installing... 1:kernel-debuginfo-3.10.0-229.el7 ################################# [100%] # rpm -q kernel-debuginfo kernel-debuginfo-3.10.0-229.el7.x86_64 # crash -s crash> sys KERNEL: /usr/lib/debug/lib/modules/3.10.0-229.el7.x86_64/vmlinux DUMPFILE: /dev/crash CPUS: 2 DATE: Mon Nov 2 12:41:58 2015 UPTIME: 00:13:18 LOAD AVERAGE: 0.37, 0.37, 0.18 TASKS: 122 NODENAME: localhost.localdomain RELEASE: 3.10.0-229.el7.x86_64 VERSION: #1 SMP Thu Jan 29 18:37:38 EST 2015 MACHINE: x86_64 (2790 Mhz) MEMORY: 2 GB -- <div class="gmail_signature"><div dir="ltr">BKS </div></div> </div></div>