From Fedora Project Wiki



  1. Prepare a NFS server, edit /etc/exports, append this line:
    /mnt/testarea/nfs *(rw,no_root_squash,sync)
    Restart NFS service:
     service nfs restart 
  2. Install Fedora on your machine
  3. After system installed, check if kexec-tools kernel-debuginfo and crash is installed via
    rpm -q kexec-tools kernel-debuginfo crash
    Or via yum
    yum install kexec-tools kernel-debuginfo crash
  4. Reserve crashkernel for kdump by grubby
    grubby --args="crashkernl=128M" --update-kernel=$(grubby --default-kernel)
    Reboot system and check /proc/cmdline
    cat /proc/cmdline | grep "crashkernel"
  5. Edit /etc/kdump.conf, add this line:
    core_collector makedumpfile -c -d 31
  6. Apply changes and start kdump via
    service kdump restart

How to test

  1. Trigger crash via:
    echo c > /proc/sysrq-trigger
  2. Use crash to analyse vmcore:
        mount -t nfs /var/crash/
        crash -i crash-simple.cmd /usr/lib/debug/lib/modules/xxx/vmlinux /var/crash/xxx/vmcore
        crash -i crash.cmd /usr/lib/debug/lib/modules/xxx/vmlinux /var/crash/xxx/vmcore

Expected Results

  1. Dump process could be monitered if console is connected
  2. System reboot successfully after dump vmcore finshed
  3. vmcore was found on NFS server
  4. No warning or error should be should found on crash output