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| Newer page: | version 27 | Last edited on Saturday, October 15, 2005 7:47:00 am | by AristotlePagaltzis | Revert |
| Older page: | version 26 | Last edited on Friday, October 14, 2005 6:20:46 pm | by JohnMcPherson | Revert |
@@ -1,80 +1,98 @@
Help! My Linux won't boot.
!!!Pre-kernel
-!!LI (on boot) (or similar)
+
+
!! <tt>
LI</tt>
(or similar,
on boot)
+
Lilo is not correctly set up. (For example, issues with old versions of lilo above block 1024 of the disk drive). See LiloErrorCodes.
-!!Loading Linux.......... Uncompressing the kernel. (stop)
-# Are you using an InitialRamdisk (initrd?) If so, do you have CONFIG_BLK_DEV_RAM and CONFIG_BLK_DEV_INITRD enabled in your kernel?
-# The kernel was compiled for a different architecture - for example, it has optimisations for [AMD] chips that don't work on an [Intel] chip, or vice-versa. If you changed the architecture of the kernel config (well, for kernel v 2.4 at least), you *need* to do a make clean afterwards, otherwise some object files that should be re-compiled aren't.
+!! <tt>
Loading Linux.......... Uncompressing the kernel.</tt>
(stop)
-!!GRUB
<blinking cursor
>
-GRUB is unable to load
it's first stage loader
, use a rescue disk to start the machine. Re
-install grub
. See
the GrubNotes page
.
+# Are you using an InitialRamdisk (initrd)? If so, do you have
<tt
>CONFIG_BLK_DEV_RAM</tt> and <tt>CONFIG_BLK_DEV_INITRD</tt> enabled in your kernel?
+# The kernel was compiled for a different architecture - for example,
it has optimisations for [AMD] chips that don
't work on an [Intel] chip
, or vice
-versa
. If you changed
the architecture of the kernel config (well, for kernel v 2.4 at least), you ''need'' to do a make clean afterwards, otherwise some object files that should be re-compiled aren't
.
-!!GRUB loading stage 2
-If this is the case your CMOS battery might have gone flat. They generally last 3-5 years and you lose your hard disk setup often if the battery dies which then causes this problem.
+!! <tt>
GRUB</tt> <blinking cursor>
-!!I get the grub
command prompt instead of my menu...
-...but if I type in "
configfile /grub/grub.conf"
the menu loads.
+[GRUB] is unable to load its first stage loader, use a rescue disk to start the machine. Reinstall [GRUB]; see the GrubNotes page.
+
+!! <tt>GRUB loading stage 2</tt>
+
+If this is the case your [CMOS] battery might have gone flat. They generally last 3-5 years and you lose your hard disk setup often if the battery dies which then causes this problem.
+
+
!! I get the [GRUB]
command prompt instead of my menu...
+
+...but if I type in <tt>
configfile /grub/grub.conf</tt>
the menu loads.
This may occur with a Mirrored SoftwareRaid setup. Reconfigure your grub.conf file and remove any reference to a root (*) device.
-<verbatim>
+
+
<verbatim>
install --stage2=/boot/grub/stage2 (hd0,0)/grub/stage1 (hd0) (hd0,0)/grub/stage2 p /grub/grub.conf
install --stage2=/boot/grub/stage2 (hd1,0)/grub/stage1 (hd1) (hd1,0)/grub/stage2 p /grub/grub.conf
quit
-</verbatim>
-NB: This assumes a seperate /boot partition
+
</verbatim>
-!I'm having the same problem, but I'm not using RAID or anything...
-From all the research I've done, it seems like problems of this sort are always caused by grub.conf mistakes. Mine seemed to be OK though, but I was still seeing problems. I noticed that when I ran
-pre
>
- setup (hd0)
-pre
>
-at the grub prompt, it mentioned a file called menu.lst . I renamed grub.conf to menu.lst, and things are now working! Apparently there may be multiple default filename possibilities for the GRUB menu file.
+NB: This assumes a seperate
<tt
>/boot
</tt
> partition
-Don
't rename grub
.conf - make a symbolic link from grub
.conf->menu
.lst (man ln)
+! I
'm having the same problem, but I'm not using [RAID] or anything
...
-!!! During kernel bootup
-!! "ESR value before enabling vector: 0000002"
-Various VIA chipset AMD Athlon/Duron motherboards (eg KT400
, KM266) running kernel 2
.4 (e
.g
. kernel 2.4.21) hang after printing this message. For example, Athlon XP2000+ on an AD77 motherboard
(KT400
), Athlon XP1800+/XP2400+ on
a PC Chips M825L (KM266))
. It is caused by [APIC] support in the kernel (not
to be confused with "ACPI")
. Booting with the "noapic" kernel flag doesn't fix it
(although it can
make the machine go into an infinite loop printing an error about apic on cpu )
. However, booting with "no__l__apic" kernel flag does in many cases work
. Recompiling the kernel without APIC support resolves this
. Note that
the same motherboards will need the "nolapic" kernel flag to boot Knoppix - otherwise the screen just turns black and the pc hangs
.
+From all the research I've done
, it seems like problems of this sort are always caused by <tt>grub
.conf</tt> mistakes
. Mine seemed to be OK though, but I was still seeing problems
. I noticed that when I ran <tt>setup
(hd0
)</tt> at the [GRUB] prompt
, it mentioned
a file called <tt>menu
.lst</tt>. I renamed <tt>grub.conf</tt>
to <tt>menu
.lst</tt>, and things are now working!
(But you should
make a SymLink from <tt>grub
.conf</tt> to <tt>menu
.lst</tt> instead of renaming
.) Apparently there may be multiple default filename possibilities for
the [GRUB] menu file
.
-!! "ACPI: setting ELCR to 0200 (from 1e20)"
-My KT400-based motherboard (that used to give the previous error message under older kernels) hangs immediately after printing this message with Ubuntu 5.10's default kernel (2.6.12-6).
-The message just before it is "ACPI: Looking for DSDT in initrd... not found
!". Again, adding "nolapic" to the kernel boot command fixes this. Note that if your distribution uses the "quiet" kernel boot flag to hide all those messages then you'll never know that it's the motherboard's acpi support at fault...
+!!! During [Kernel] bootup
-!! Warning
: unable to open an initial console
-This is usually caused by a failure to find or mount
/dev or a bad /dev being used. When remastering [Knoppix] this can be cause by failing to preserve the special nature of the device files under /dev while building remastering. See the "dev" option of the mount(8)
+!! <tt>ESR value before enabling vector
: 0000002<
/tt>
+Various VIA chipset [AMD] Athlon/Duron motherboards (eg KT400, KM266) running kernel 2.4 (e.g. kernel 2.4.21) hang after printing this message. For example, Athlon XP2000+ on an AD77 motherboard (KT400), Athlon XP1800+/XP2400+ on a PC Chips M825L (KM266)). It is caused by [APIC] support in the kernel (not to be confused with [ACPI]). Booting with the <tt>noapic</tt> kernel flag doesn't fix it (although it can make the machine go into an infinite loop printing an error about apic on cpu 0). However, booting with <tt>no__l__apic</tt> kernel flag does in many cases work. Recompiling the kernel without APIC support resolves this. Note that the same motherboards will need the <tt>nolapic</tt> kernel flag to boot Knoppix - otherwise the screen just turns black and the computer hangs.
+!! <tt>ACPI: setting ELCR to 0200 (from 1e20)</tt>
-!!!Starting services
+My KT400-based motherboard (that used to give the previous error message under older kernels) hangs immediately after printing this message with [Ubuntu] 5.10's default kernel (2.6.12-6). The message just before it is <tt>ACPI: Looking for DSDT in initrd... not found
!</tt> Again, adding <tt>nolapic</tt> to the kernel boot command fixes this. Note that if your distribution uses the <tt>quiet</tt> kernel boot flag to hide all those messages then you'll never know that it's the motherboard's [ACPI] support at fault...
-; __
modprobe - Cannot find module char-major-??__ :
Devices in Linux have major and minor numbers (unless you use the newer DevFs) Devices need to be implemented by the [Kernel], either compiled in directly, or via a loadable [Module]. For example, serial ports are on char-major-4; eg "
ls -l /dev/ttyS0"
shows major device number 4 and minor device number 64...
-<verbatim>
+!! <tt>Warning: unable to open an initial console</tt>
+
+This is usually caused by a failure to find or mount <tt>/dev</tt> or a bad <tt>/dev</tt> being used. When remastering [Knoppix] this can be cause by failing to preserve the special nature of the device files under <tt>/dev</tt> while building remastering. See the <tt>dev</tt> option of mount(8).
+
+!!! Starting services
+
+!! <tt>
modprobe - Cannot find module char-major-''##''</tt>
+
+
Devices in [
Linux]
have major and minor numbers (unless you use the newer DevFs).
Devices need to be implemented by the [Kernel], either compiled in directly, or via a loadable [Module]. For example, serial ports are on <tt>
char-major-4</tt>
; eg <tt>
ls -l /dev/ttyS0</tt>
shows major device number 4 and minor device number 64...
+
+ <verbatim>
crw-rw---- 1 root dialout 4, 64 Feb 10 1998 /dev/ttyS0
major ^ ^^ minor
-</verbatim>
-; : A common problem char-major-10 is misc devices such as psaux, watchdog, apm and nvram - "cat /proc/misc" should list the ones you're using. You will probably need to do some configuration in /etc/modules or /etc/modules.conf(5). Normally these messages don't cause problems later in life, but it's nice to have them cleaned up. %%% %%% The allocation of each number to its respective device can be looked up in the file /usr/src/linux-your_kernel_version/Documentation/devices.txt, provided the kernel sources have been installed. In this file you can find out what device and module are affected. It does not have to be an error, but perhaps only information about the module not having to be loaded any more because it is already loaded or is not required.
+
</verbatim>
+A common problem char-major-10 is misc devices such as psaux, watchdog, apm and nvram - <tt>cat /proc/misc</tt> should list the ones you're using. You will probably need to do some configuration in <tt>/etc/modules</tt> or <tt>/etc/modules.conf</tt> (see modules.conf(5)). Normally these messages don't cause problems later in life, but it's nice to have them cleaned up.
+
+The allocation of each number to its respective device can be looked up in the file <tt>/usr/src/linux-''$VERSION''/Documentation/devices.txt</tt>, provided the [Kernel] sources have been installed. In this file you can find out what device and module are affected. It does not have to be an error, but perhaps only information about the module not having to be loaded any more because it is already loaded or is not required.
+
+To see what module you're missing, use
+
+ <verbatim>
grep char-major-10-135 /etc/modutils/arch/i386
-; : That'll tell you what module you're missing.
+ </verbatim>
-* char-major-6 is the parallel port and can be fixed by compiling CONFIG_PARPORT=m.
-* char-major-10-135 is the Enhanced Realtime Clock and can be fixed by compiling CONFIG_RTC=m.
+* <tt>
char-major-6</tt>
is the parallel port and can be fixed by compiling <tt>
CONFIG_PARPORT=m</tt>
+* <tt>
char-major-10-135</tt>
is the Enhanced Realtime Clock and can be fixed by compiling <tt>
CONFIG_RTC=m</tt>
See KernelErrorMessages for more information about missing modules.
-!!!Runlevel 2 and beyond
+!!! Runlevel 2 and beyond
-__
Loading syslog... (5 minute pause) %%%
Loading MTA... (5 minute pause) %%%
Loading apache...failed__
- Your problem is [DNS], or the lack thereof. These services will all want to look up names in their configuration (normally your local machine name) and will be taking a month of sundays to time out as a result. Confirm this by typing 'host mydomain.tla' at the root prompt.
+!! <tt>
Loading syslog...</tt>
(5 minute pause) <br> <tt>
Loading MTA...</tt>
(5 minute pause) <br> <tt>
Loading apache... failed</tt>
-
A good solution for this is to make sure that your /etc/hostname file (which is set using hostname(1)) also appears in your /etc/hosts file, like such:
-<verbatim>
+Your problem is [DNS], or the lack thereof. These services will all want to look up names in their configuration (normally your local machine name) and will be taking a month of sundays to time out as a result. Confirm this by typing <tt>host mydomain.tla</tt> at the root prompt.
+
+
A good solution for this is to make sure that your /etc/hostname file (which is set using hostname(1)) also appears in your /etc/hosts file, like such:
+
+ <verbatim>
127.0.0.1 localhost full.local.domain.name alias1 alias2
-</verbatim>
-
Eg:
-<verbatim>
+
</verbatim>
+
+
Eg:
+
+ <verbatim>
127.0.0.1 localhost firewall.wiki.invalid firewall
-</verbatim>
- (
Remember, /etc/hostname should contain the shortened version of the name, '
firewall'
, not the [FQDN])
, and the first name for 127...1 in /etc/hosts should be '
localhost'
+
</verbatim>
+
+
Remember, <tt>
/etc/hostname</tt>
should contain the shortened version of the name, <tt>
firewall</tt>
, not the [FQDN], and the first name for 127...1 in <tt>
/etc/hosts</tt>
should be <tt>
localhost</tt>.
