Hello,
I have recently been experimenting building my own kernel and have run into some trouble. I feel my first problem is reading the messages outputted during boot-up.

Why are some lines displayed during boot-up but are omitted in /var/log/dmesg?

During boot-up, I can see something about VFS:... and then many hundred lines quickly scroll by looking similar to the following:
udev[349]: delete_path: rmdir(/dev/.udev/failed) failed: Read-only file system

When I check dmesg, there is no mention of any of the above errors.

chris

I don't know why log does differ than what is on the screen but if you wish to review you can try this. I don't know the distro or version you have but here is an example of a Redhat distro to review what is on the screen.

When the grub boot manager comes up hit the 'e' key then if it is a default grub then you move up or down with the arrow key to highlight the kernel you boot. Usually defaults it. Then hit ' e ' again and you have the boot kernel configuration. arrow down to the vmlinuz line and hit ' e' again. Arrow to the end of the line and if there is the words like rghb and quiet remove those and add the number ' 3 ' to it. Hit ' b ' to boot the kernel into runlevel 3. Once booted you are at a login prompt. Hold down the left shift key and then hit page up key to scroll back. Should see everything that went to the screen from start to finish.

Brian

I am using slackware 12.0, linux kernel 2.6.24.3.

After boot-up I can use right-shift+pgup to see some of the boot messages but since there are so many of the mentioned udev lines, the buffer fills up and I cannot see what happens at the beginning.

chris

No ideas as to the cause. Might google for like a portion of the error and get an idea to the cause.

Brian

Try checking '/var/log/syslog' and '/var/log/messages'. Those two combined should have everything output to the screen and more.

I've checked these two files but there is no mention of the udev errors I am receiving.

btw, there may be a bunch of errors with a cp operation just before the mentioned udev problems. It flashes too quickly to be sure though.

Any other ideas??

chris

Try hitting the pause/break key on your keyboard during the boot process - it should pause the output as it's going by, so you can make a note of it.

To resume the boot process, press pause/break again, or hit enter.

See http://en.wikipedia.org/wiki/Break_key for more info (apparently, Ctrl+NumLock has the same effect).

I tried both and neither paused the output. I also tried some combinations of CTRL+pause, ALT+pause... nothing. Am I missing something??

chris

No, I don't think so. It works for me, if I remember rightly. Sorry :/

I guess what I am looking for is where do I find udevmonitor's output. This is not in /var/log/syslog or /var/log/messages no matter what udev_log level is set to.

Anybody know?

thanks for the help so far,
chris

maybe a bit elementary, but I've found the scroll lock key to pause the start-up. Not much immediate need for the log anymore...

thanks for the suggestions,

chris

As for dmesg not matching what you see on screen: that's because
dmesg is a window into the kernel ring-buffer. Problems
with scripts are NOT on kernel level, hence won't show there.



Cheers,
Tink