Misc. Linux questions.
 

HI, I've been fiddling with Linux for the past few weeks
and I've got some queries...

1. Where an I find a compendium of information
on the boot sequence of a Linux box. ie from the
OS loader all the way up to the shell login script.
Something that is preferably written in the style of
Windows Internals.

2. How can I determine the major device numbers which
are in use? Is there some official numbering scheme?
What if a new piece of hardware comes out? How
does the driver writer know which number to be
assigned?

3. Can root not be named 'root'. Can it called something
else (ie w/o having to recompile anything).

4. Can I install a minimal bare bones installation
using just a floppy disk? What are the files I need
and how should I configure the system? Can it
run w/o a hard disk (page file???). I'm trying to
create a custom rescue disk.
5. My /dev/hdc is listed as a block device with major
ver 22 and minor ver 0 during an ls, but when I try
to mount it, it says that /dev/hdc is not a valid
block device. What gives?

6. After I mount my floppy, I would periodically get error
messages (some interrupt error. Cant remeber exactly
what). Why?

Thanks.

Welcome to LQ.

1: On The Linux Documentation Project there's a HOWTO somewhere called something like 'From startup to bash prompt' which takes you through all the processes and stuff. Can be quite heavy going, though.

2: Again, from the above link, there's a HOWTO on hardware and naming/numbering schemes.

3: You can make another user that has (almost?) all the priveledges of root, but I don't think you can actually remove the user 'root' because it is used to run services on startup, or something.

4: There are many, many, many bare-bones Linux 'distros' around. The favourite by many has got to be Tom's RTBT - but it's not the only one. Check out Ibiblio's Linux distro list.

5: Err, not sure. Is it a valid device (i.e. is there actually a device attached to 2ndry Master?), and does it have a filesystem? It it's a ZIP drive, you'll need to have 'hdc=ide-floppy' in tje append section of your lilo.conf

6: Not sure, but could be a bad floppy. Personally I don't mount floppies (unless they're ext2, which is very few), I use the mtools to access Win/DOS floppies.

Hope this helps.

About the small linux take a look at http://tiny.seul.org/. It is tiny Linux, can be installed from floppies!!

As for block device problem, I had the same on Red Hat 7.2, It took a week to find a solution thanks to linuxcool ! Try depmod -ae. I'm not sure what it does exactly but it fixed the block device problem with my CD-Rom and resolve the problem I had with the floppy. ( I could not mount the floppy)

Hope this helps!

No it didnt really. I couldn't find the page for the numbering scheme. Could you post the link here? Thx.

Re: Misc. Linux questions.
 

You don't want to rename root. I promise you don't. Many of the processes running are owned by root. I'm curious what horrible things would happen if you tried to do this but I'm not going to be the one to try it. :D

to mount a drive you need to give a partition number, not just a device. if there is only one partition then the number is 1.
so try 'mount /dev/hdc1 /mnt/<mount point>'. you may also need to specify type with '-t'.
to mount hdc w/ 1 partition with a fat32 FS:
'mount /dev/hdc1 /mnt/fat32 -t vfat'
of course the dir /mnt/fat32 must already exist. if you are trying to mount an ntfs drive be sure to use '-o ro' to mount the drive as read-only or you will make the drive unreadable to windows (although linux will still have access to it). also try 'man mount' for more info on the mount command.

Sorry, buddy. I was almost certain that it was on LDP. Perhaps it's in the kernel source tree somewhere? Anyhow, a google.com/linux search comes up with about 7000 matches...

some answers
 

2. about device no scheme

check

Documentation/devices.txt file in your source code path

i have path
/usr/src/linux-2.4.2/Documentation/devices.txt


3 . you can do one trick

create one user for example mydemo

edit /etc/passwd fle

change user id of that user 0 , & group id too ,

ie. if u have line
mydemo:x:501:501::/home/mydemo:/bin/bash

change it to
mydemo:x:0:0::/root:/bin/bash

you have created synonym for root

so root is not recognised as root name but any user with user id as 0 & group id 0 have root previlages.


6 . is error look someting like
floppy 0 : data CRC error: ......

it is because of bad sectors on floppy (i often see this error to my floppies)

I observed this error start only when i have some bad sectors in my floppy , even scandisk from windows & repairing floppies I dosen't always successful to prevent this error