How to debug Dracut problems2

From FedoraProject

Jump to: navigation, search


This page describes how to debug Dracut. For general information on how to file a bug, should you need to do so, please see Bugs and feature requests.

Contents

Identifying your problem area

  1. Remove rhgb and quiet from the kernel command line
  2. Add rdshell to the kernel command line. This will present a shell should dracut be unable to locate your root device
  3. Add rdshell rdinitdebug to the kernel command line so that dracut shell commands are printed as they are executed
  4. With dracut >= 002-11 [1], you can inspect the rdinitdebug output with:
    # less /init.log
    # dmesg | less

Information to include in your report

All bug reports

In all cases, the following should be mentioned and attached to your bug report:

  • The exact kernel command-line used. Typically from the bootloader configuration file (e.g. /etc/grub.conf) or from /proc/cmdline
  • A copy of your disk partition information from /etc/fstab
  • A device listing from device-mapper. This can be obtained by running the command dmsetup ls --tree
  • A list of block device attributes including vol_id compatible mode. This can be obtained by running the commands blkid and blkid -o udev
  • Turn on dracut debugging (see the 'debugging dracut' section), and attach all relevant information from the boot log. This can be obtained by running the command dmesg|grep dracut.
  • If you use a dracut configuration file, please include /etc/dracut.conf

Logical Volume Management related problems

As well as the information from the 'all bug reports' section, include the following information:

  • Include physical volume information by running the command: lvm pvdisplay
  • Include volume group information by running the command: lvm vgdisplay
  • Include logical volume information by running the command: lvm lvdisplay

Software RAID related problems

As well as the information from the 'all bug reports' section, include the following information:

  • If using software RAID disk partitions, please include the output of /proc/mdstat

Network root device related problems

This section details information to include when experiencing problems on a system whose root device is located on a network attached volume (e.g. iSCSI, NFS or NBD). As well as the information from the 'all bug reports' section, include the following information:

  • Please include the output of ip addr show