Difference between revisions of "Installing LILO"

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{{todo|Complete (12.16.13-03:15->MD+);(12.16.13-12:50->MD);(12.16.13-13:40->MD);(12.16.13-13:45->MW+);(12.16.13-18:20->KY+)|Mike Dean|project=oe 4,oe 5,md,Complete,mw,ky}}
 
{{todo|Complete (12.16.13-03:15->MD+);(12.16.13-12:50->MD);(12.16.13-13:40->MD);(12.16.13-13:45->MW+);(12.16.13-18:20->KY+)|Mike Dean|project=oe 4,oe 5,md,Complete,mw,ky}}
  
==Installing LILO==
+
==Introduction==
  
 
LILO can be installed onto a disk for use by the local machine, or it can be installed onto a removable storage device for use in booting on a different machine.  Both installation methods are discussed here.  Usually, the former method will be used to update the existing bootloader for new kernels, new kernel configurations, or new boot time options.  The latter method is generally used to initially set up a bootable storage device which is intended to be inserted into an embedded system for which it is being created.
 
LILO can be installed onto a disk for use by the local machine, or it can be installed onto a removable storage device for use in booting on a different machine.  Both installation methods are discussed here.  Usually, the former method will be used to update the existing bootloader for new kernels, new kernel configurations, or new boot time options.  The latter method is generally used to initially set up a bootable storage device which is intended to be inserted into an embedded system for which it is being created.
  
===Installing Onto the Local Machine===
+
==Installing Onto the Local Machine==
  
Before LILO can be used to boot a system, it must be installed onto the boot device.  It must also be reinstalled any time the configuration is changed, or the new configuration will not take effect.  Fortunately, installing LILO is easy.
+
Before LILO can be used to boot a system, it must be installed onto the boot device.  It must also be reinstalled any time the kernel is changed.
 
+
The easiest way to install LILO onto the system's Master Boot Record, using the default configuration file (<code>/etc/lilo.conf</code>), is run lilo on the target device:
The easiest way to install LILO onto the local system's Master Boot Record, using the default configuration file (<code>/etc/lilo.conf</code>), is to type:
 
  
 
  root@oe:/# lilo
 
  root@oe:/# lilo
  
This method works well for systems where only a small change is required to the default configuration, but is not often what is desired on an embedded system. Many times, an alternate file will be used to store the new configuration so that a breaking change to a known-good configuration file will not leave the system without a usable configuration file.  If a configuration file in an alternate location needs to be used, it will have to be specified like this:
+
This method works well when the default configuration can be used. Many times, an alternate configuration will be used so that a breaking change to a known-good configuration file will not leave the system without a usable configuration file.  If a configuration file in an alternate location needs to be used, it will have to be specified to lilo with the -C option:
 
   
 
   
 
  root@oe:/# lilo -C /etc/alternate_lilo_configuration_file.conf
 
  root@oe:/# lilo -C /etc/alternate_lilo_configuration_file.conf
Line 19: Line 18:
 
The <code>-C</code> (capital C) switch tells <code>lilo</code> to use the configuration file specified after the switch when installing itself.
 
The <code>-C</code> (capital C) switch tells <code>lilo</code> to use the configuration file specified after the switch when installing itself.
  
===Installing LILO Onto a Removable Drive===
+
==Installing LILO Onto a Removable Drive==
  
The last method shown above is not what is needed when the embedded machine's root drive is not in the running embedded system. With a Compact Flash disk, for instance, containing the Linux filesystem and mounted on a desktop Linux development machine, a few hoops need to be jumped through in order to install the bootloader onto the Compact Flash card. This method is usually necessary when there isn't already a bootable disk for the embedded machine.
+
The method shown above is used on a running embedded system. Additional steps are required when the root filesystem is on a Compact Flash card inserted into a Linux PC. This method is usually necessary when there isn't already a bootable disk for the embedded machine.
 +
<cl>
 +
1. Determine the device node of the Compact Flash card by using <code>dmesg</code>.
  
Two sets of directions for doing this are given hereThe first set of directions is generic, and will work for desktop Linux distributions which do not include an automounter or have an automounter which doesn't interfere with the processThe second set details a known workaround. The following steps will need to be performed to install LILO onto a removable drive:
+
user@ldc:~/# dmesg | tail -n 15
 +
...
 +
[126468.154762] sd 6:0:0:0: [sdb] 7831152 512-byte logical blocks: (4.00 GB/3.73 GiB)
 +
[126468.182196]  sdb: sdb1
 +
[126468.688061] kjournald starting.  Commit interval 5 seconds
 +
[126468.691223] EXT3-fs (sdb1): using internal journal
 +
[126468.691225] EXT3-fs (sdb1): recovery complete
 +
[126468.694526] EXT3-fs (sdb1): mounted filesystem with ordered data mode
 +
[173828.541718] sdb: detected capacity change from 4009549824 to 0
 +
[179577.977554] sd 6:0:0:0: [sdb] 7831152 512-byte logical blocks: ('''4.00 GB/3.73 GiB''')
 +
[179577.994839] '''sdb:''' '''sdb1'''
 +
[179578.376157] kjournald starting.  Commit interval 5 seconds
 +
[179578.381428] EXT3-fs (sdb1): using internal journal
 +
  [179578.381433] EXT3-fs (sdb1): recovery complete
 +
[179578.384661] EXT3-fs (sdb1): mounted filesystem with ordered data mode
  
====Installing from a System with No Automounter or a Non-Interfering Automounter====
+
* The device node <code>sdb</code> was created for the flash card with one partition <code>sdb1</code>(in this example). Also note that <code>sdb</code> reports a size of 4.00 GB which corresponds to the size of the card inserted.
  
For simpler systems without an automounter, or with an automounter that doesn't try to protect the user from possibly malicious code, follow these directions.
+
* Determine if the card was automatically mounted to the desktop's filesystem. Problems have been identified when running lilo on an automounted device. The best way to avoid problems later in the process is to unmount and manually remount the device.
  
<cl>1. Mount the drive.
+
<syntaxhighlight lang="console">
i. Insert the flash card into the development system's card reader.
+
developer@ldc:~$ mount | grep sdb1
* Find out where the device node for the card was created (assuming the development machine uses <code>udev</code>) by using <code>dmesg</code>.<syntaxhighlight lang="console">
+
/dev/sdb1 on /media/EMAC-OE type ext3 (rw,nosuid,nodev,uhelper=udisks)
user@ldc:~/# dmesg | tail -n 15
 
...
 
[126468.154762] sd 6:0:0:0: [sdb] 7831152 512-byte logical blocks: (4.00 GB/3.73 GiB)
 
[126468.182196]  sdb: sdb1
 
[126468.688061] kjournald starting.  Commit interval 5 seconds
 
[126468.691223] EXT3-fs (sdb1): using internal journal
 
[126468.691225] EXT3-fs (sdb1): recovery complete
 
[126468.694526] EXT3-fs (sdb1): mounted filesystem with ordered data mode
 
[173828.541718] sdb: detected capacity change from 4009549824 to 0
 
[179577.977554] sd 6:0:0:0: [sdb] 7831152 512-byte logical blocks: (4.00 GB/3.73 GiB)
 
[179577.994839]  sdb: sdb1
 
[179578.376157] kjournald starting.  Commit interval 5 seconds
 
[179578.381428] EXT3-fs (sdb1): using internal journal
 
[179578.381433] EXT3-fs (sdb1): recovery complete
 
[179578.384661] EXT3-fs (sdb1): mounted filesystem with ordered data mode
 
 
</syntaxhighlight>
 
</syntaxhighlight>
  * Since the device node <code>sdb1</code> was created for the flash card (in this example), that device needs to be mounted somewhere accessible. In this example, the <code>/mnt/cfcard</code> directory is used:<syntaxhighlight lang="console">
+
 
 +
  * If there is no output from this command, continue with step 3. Otherwise follow the next step to unmount the device.
 +
 
 +
  user@ldc:~/# umount /dev/sdb1
 +
 
 +
* Now mount the card so that it's contents can be accessible to the desktop. First create a mount point (directory) if one does not exist, then issue the <code>mount</code> command.
 +
 
 +
<syntaxhighlight lang="console">
 
user@ldc:~/# sudo su
 
user@ldc:~/# sudo su
 
[sudo] password for user:
 
[sudo] password for user:
Line 55: Line 62:
 
root@ldc:~/#  
 
root@ldc:~/#  
 
</syntaxhighlight>
 
</syntaxhighlight>
 +
 
* Bind mount the device nodes into the filesystem so that LILO will be able to communicate with the flash card:
 
* Bind mount the device nodes into the filesystem so that LILO will be able to communicate with the flash card:
 
  root@ldc:~/# cd /mnt/cfcard
 
  root@ldc:~/# cd /mnt/cfcard
Line 60: Line 68:
 
  root@ldc:/mnt/cfcard#  
 
  root@ldc:/mnt/cfcard#  
  
* <code>chroot</code> into the filesystem:
+
* <code>chroot</code> into the filesystem on the Compact Flash card:
 
  root@ldc:/mnt/cfcard# chroot .
 
  root@ldc:/mnt/cfcard# chroot .
  root@ldc:/#  
+
  bash-3.2#  
  
* Run <code>lilo</code> with the appropriate LILO configuration file.  Be sure to double check to ensure that the configuration file is correct, because a mistake here could render the desktop system unbootable.
+
* Inspect the configuration file that will be used when running lilo e.g. lilo.conf.boot. Make sure that the <code>root=/dev/xxx</code> and <code>disk=/dev/xxx</code> lines point to the correct device node that the Compact Flash card is mounted on (in this example, <code>/dev/sdb</code>). If these lines point to the desktop hard drive, the system bootloader will be overwritten and cause the desktop to be unbootable See [[Configuring LILO]] for more information.  
  root@ldc:/# lilo -C /etc/lilo.conf.boot
+
 
 +
* Run <code>lilo</code> with the appropriate LILO configuration file.
 +
 
 +
<syntaxhighlight lang=console>
 +
  bash-3.2# lilo -C /etc/lilo.conf.boot
 
  Warning: '/proc/partitions' does not exist, disk scan bypassed
 
  Warning: '/proc/partitions' does not exist, disk scan bypassed
 
  Added emac-oe *
 
  Added emac-oe *
 
  One warning was issued.
 
  One warning was issued.
  root@ldc:/#
+
  bash-3.2#
Note that the warning here is normal, because LILO is being installed inside a chroot which doesn't have a mounted <code>/proc</code> virtual filesystem.
+
</syntaxhighlight>
 +
 
 +
* Note that the warning here is normal, because LILO is being installed inside a chroot which doesn't have a mounted <code>/proc</code> virtual filesystem.
 +
 
 
* Exit the chroot and unmount the device:
 
* Exit the chroot and unmount the device:
  root@ldc:/# exit
+
   
 +
bash-3.2# exit
 
  root@ldc:/mnt/cfcard# cd ..
 
  root@ldc:/mnt/cfcard# cd ..
  root@ldc:/mnt# umount cfcard
+
  root@ldc:/mnt# umount cfcard/dev/
 +
root@ldc:/mnt# umount cfcard/
  
 
* It is now safe to remove the flash card and put it into the embedded machine.
 
* It is now safe to remove the flash card and put it into the embedded machine.
 
</cl>
 
</cl>
  
====Workaround for the Ubuntu Automounter (and Possibly Others)====
+
==Next Steps==
  
On many Linux desktops, a memory card will be automounted when it is inserted.  While this is a nice convenience feature for most users, it comes at the expense of developers.  This automount feature can be a source of frustration for those who haven't already found a way around the issues it causes.
+
* [[Configuring LILO]]
 
 
Fortunately, we at EMAC have already found a method which works reliably on our recommended Linux distribution, Ubuntu 12.04 LTS, and have documented it here. On other systems, such as Debian, a workaround may not be needed.  For a system which automounts, see below.
 
 
 
<cl>1. Insert the flash card into the development machine's card reader and wait for the file browser window to appear.  If a messagebox appears asking you to choose what to do, tell it to open a file browser for browsing the files on the card.
 
* Keep the file browser window open, and stash it away for later use.
 
* Open a terminal and create a <code>/mnt/cfcard</code> directory, if it does not exist:
 
user@ubuntu:/# mkdir /mnt/cfcard
 
* Find out the device name of the card by looking for the location where the card was mounted.  The file browser window will list the name of the card under Devices in the left pane.  Often times, the name will be EMAC_OE.  Look for this name in the output of the <code>df</code> command:
 
user@ubuntu:/# df -hT | grep EMAC
 
/dev/sdb1                      ext3      3.7G  223M  3.3G  7% /media/EMAC_OE
 
* From the output of this command, we can see that the <code>/media/EMAC_OE</code> mountpoint was mounted onto the <code>/dev/sdb1</code> device.  Therefore, this is the device needed for the next step.
 
* Mount the device on the directory from step 3, without unmounting it first:
 
user@ubuntu:/# mount /dev/sdb1 /mnt/cfcard
 
user@ubuntu:/#
 
* Now, switch to the root user account (if not already running as root) and bind mount the host system's <code>/dev</code> directory to the cfcard's <code>/dev</code> directory.  This will provide the device node file that will be needed for LILO to be able to talk to the flash card.
 
user@ubuntu:/# sudo su
 
[sudo] password for user:
 
root@ubuntu:/# cd /mnt/cfcard
 
root@ubuntu:/mnt/cfcard#
 
root@ubuntu:/mnt/cfcard# mount --bind /dev dev/
 
root@ubuntu:/mnt/cfcard#
 
  
* Now, use the <code>chroot</code> command to make the directory where the card is mounted the effective root directory for this terminal session:
+
==See Also==
root@ubuntu:/mnt/cfcard# chroot .
 
root@ubuntu:/#
 
  
* Now that the shell is effectively running inside the filesystem on the flash card, LILO can be run to install the bootloader.  First, be sure to double check to ensure that the configuration file you're using points to the correct device node (in this example, <code>/dev/sdb1</code>) so that you don't overwrite the bootloader on your desktop (see [[Configuring LILO]] for more information).  If you overwrite the bootloader on your desktop, '''it will render your desktop system unbootable!'''  So make sure to double check this if you value the ability to boot your desktop.
+
[http://lilo.alioth.debian.org/olddoc/html/user_21-5.html Lilo User Guide]
* When you are sure you're using the right device node, run LILO to install the bootloader:
 
root@ubuntu:/# lilo -C /etc/lilo.conf.boot
 
Warning: '/proc/partitions' does not exist, disk scan bypassed
 
Added emac-oe *
 
One warning was issued.
 
root@ubuntu:/#
 
The warning, in this case, is normal.  It appears because this is a fake "running system," which means the virtual files in the <code>/proc/</code> filesystem aren't mounted and able to provide information; hence, the non-existence of the <code>/proc/partitions</code> file.
 
* Now, you need to umount the device:
 
root@ubuntu:/# exit
 
root@ubuntu:/mnt/cfcard# cd ..
 
root@ubuntu:/mnt# umount cfcard/dev
 
root@ubuntu:/mnt# umount cfcard
 
root@ubuntu:/mnt# exit
 
user@ubuntu:/#
 
 
 
* Retrieve the file browser that was stashed away earlier, and unmount the automounted directory for the card by clicking on the eject symbol next to the name of the device in the left pane.
 
 
 
* It is now safe to eject the card and put it into the embedded machine.
 
</cl>
 
 
 
==Next Steps==
 
 
 
* [[Configuring LILO]]
 

Revision as of 14:11, 19 December 2013

TODO: {{#todo:Complete (12.16.13-03:15->MD+);(12.16.13-12:50->MD);(12.16.13-13:40->MD);(12.16.13-13:45->MW+);(12.16.13-18:20->KY+)|Mike Dean|oe 4,oe 5,md,Complete,mw,ky}}

Introduction

LILO can be installed onto a disk for use by the local machine, or it can be installed onto a removable storage device for use in booting on a different machine. Both installation methods are discussed here. Usually, the former method will be used to update the existing bootloader for new kernels, new kernel configurations, or new boot time options. The latter method is generally used to initially set up a bootable storage device which is intended to be inserted into an embedded system for which it is being created.

Installing Onto the Local Machine

Before LILO can be used to boot a system, it must be installed onto the boot device. It must also be reinstalled any time the kernel is changed. The easiest way to install LILO onto the system's Master Boot Record, using the default configuration file (/etc/lilo.conf), is run lilo on the target device:

root@oe:/# lilo

This method works well when the default configuration can be used. Many times, an alternate configuration will be used so that a breaking change to a known-good configuration file will not leave the system without a usable configuration file. If a configuration file in an alternate location needs to be used, it will have to be specified to lilo with the -C option:

root@oe:/# lilo -C /etc/alternate_lilo_configuration_file.conf

The -C (capital C) switch tells lilo to use the configuration file specified after the switch when installing itself.

Installing LILO Onto a Removable Drive

The method shown above is used on a running embedded system. Additional steps are required when the root filesystem is on a Compact Flash card inserted into a Linux PC. This method is usually necessary when there isn't already a bootable disk for the embedded machine.

  1. Determine the device node of the Compact Flash card by using dmesg.

    user@ldc:~/# dmesg | tail -n 15
    ...
    [126468.154762] sd 6:0:0:0: [sdb] 7831152 512-byte logical blocks: (4.00 GB/3.73 GiB)
    [126468.182196]  sdb: sdb1
    [126468.688061] kjournald starting.  Commit interval 5 seconds
    [126468.691223] EXT3-fs (sdb1): using internal journal
    [126468.691225] EXT3-fs (sdb1): recovery complete
    [126468.694526] EXT3-fs (sdb1): mounted filesystem with ordered data mode
    [173828.541718] sdb: detected capacity change from 4009549824 to 0
    [179577.977554] sd 6:0:0:0: [sdb] 7831152 512-byte logical blocks: (4.00 GB/3.73 GiB)
    [179577.994839]  sdb: sdb1
    [179578.376157] kjournald starting.  Commit interval 5 seconds
    [179578.381428] EXT3-fs (sdb1): using internal journal
    [179578.381433] EXT3-fs (sdb1): recovery complete
    [179578.384661] EXT3-fs (sdb1): mounted filesystem with ordered data mode
    
    • The device node sdb was created for the flash card with one partition sdb1(in this example). Also note that sdb reports a size of 4.00 GB which corresponds to the size of the card inserted.

  2. Determine if the card was automatically mounted to the desktop's filesystem. Problems have been identified when running lilo on an automounted device. The best way to avoid problems later in the process is to unmount and manually remount the device.

    developer@ldc:~$ mount | grep sdb1
    /dev/sdb1 on /media/EMAC-OE type ext3 (rw,nosuid,nodev,uhelper=udisks)
    
    • If there is no output from this command, continue with step 3. Otherwise follow the next step to unmount the device.

      user@ldc:~/# umount /dev/sdb1
      
  3. Now mount the card so that it's contents can be accessible to the desktop. First create a mount point (directory) if one does not exist, then issue the mount command.

    user@ldc:~/# sudo su
    [sudo] password for user:
    root@ldc:~/# mkdir -p /mnt/cfcard
    root@ldc:~/# mount /dev/sdb1 /mnt/cfcard
    root@ldc:~/#
    
  4. Bind mount the device nodes into the filesystem so that LILO will be able to communicate with the flash card:

    root@ldc:~/# cd /mnt/cfcard
    root@ldc:/mnt/cfcard# mount --bind /dev dev/
    root@ldc:/mnt/cfcard# 
    
  5. chroot into the filesystem on the Compact Flash card:

    root@ldc:/mnt/cfcard# chroot .
    bash-3.2# 
    
  6. Inspect the configuration file that will be used when running lilo e.g. lilo.conf.boot. Make sure that the root=/dev/xxx and disk=/dev/xxx lines point to the correct device node that the Compact Flash card is mounted on (in this example, /dev/sdb). If these lines point to the desktop hard drive, the system bootloader will be overwritten and cause the desktop to be unbootable See Configuring LILO for more information.

  7. Run lilo with the appropriate LILO configuration file.

     bash-3.2#  lilo -C /etc/lilo.conf.boot
     Warning: '/proc/partitions' does not exist, disk scan bypassed
     Added emac-oe *
     One warning was issued.
     bash-3.2#
    
    • Note that the warning here is normal, because LILO is being installed inside a chroot which doesn't have a mounted /proc virtual filesystem.

  8. Exit the chroot and unmount the device:

    bash-3.2#  exit
    root@ldc:/mnt/cfcard# cd ..
    root@ldc:/mnt# umount cfcard/dev/
    root@ldc:/mnt# umount cfcard/
    
  9. It is now safe to remove the flash card and put it into the embedded machine.

Next Steps

See Also

Lilo User Guide