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Old 09-17-2006, 07:46 AM   #1
WhatsOnYourBrain
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Unhappy seek advice re: syntax: "ro root"?


how i arrived in this situation, i've described here:
http://forums.fedoraforum.org/showthread.php?t=124441
I mention it because, from what i've read-- no one else has a Kernel Panic issue from problems which began under the normal OS operation, but rather under installations, or upgrades-- this is NOT the situation here.
but maybe that's not relevant?-- so, at this point, i'm trying to focus on a solution, regardless of the cause. therefore, i'm looking for help with:

GRUB - what can i do there? what can it "do for me"?
Kernel (and actions related to "recompiling" it?)
How much "damage" can i do to existing Data by playing w/ miscellaneous parameters while in a state of "Kernel Panic"?
Is the damage i've already done to the once perfectly functional Filesystem-- irreperable? is there any point in my troubling over this, or is it shot already by the looks of things?

i'm afraid to move on and try some stuff for fear of further disrupting my chances of recovering existing data. i'm not going to foolishly pretend to know how to proceed, so the best i can think of is to try to illustrate what's going on, so maybe someone can tell me what to read, what to try, etc.
i feel so ignorant about the situation, so i've got to fill that gap by learning. sorry to ramble, but since i don't know the technical, it's all i can do. i appreciate your patience if you'll read on...

i know i've got the Filesystem, i've got root and the system users (and all the knowledge thereof from learning about configuring localhost, for example from Gnome or KDE). yet, i can not "see" any of that. the GRUB commandline (if that's what it truly is), as described below, doesn't show me what i'm used to seeing. for example, if i'd type "cd ~", there's no "home" directory, and "root" has nothing in it. i have vague knowledge of the 2 partitions -- the filesystem partition (the big one) and the "boot" partition(?) just a little one. i must assume that at this point, i'm looking at stuff from the "little" boot partition? see-- i'm clueless!

here's basically what's happening: Fedora Core 5 (recently updated to new Kernel-- but i'm convinced my problem is due to my own CLI command executed--i believe i may have accidentally "erased" or "wrote over" /root/ somehow)

1. cold boot
2. boots "normally" into Fedora GRUB graphical screen -- where i have the option to hit a key and enter a mode to customize... i guess it's the "Kernel Arguments"?
3. hit any key -- now i've got options:
a) 'e' to edit
b) 'a' to append or adjust the arguments
c) 'c' commandline ("Bash-like functions...")
[i hope i've named those correct]

4a. try 'c': now i have a prompt GRUB> from which i can view a short help menu list which contains no info which is useful to me. (ie. "rootnoverify looks interesting!")
4b. 'a' - again, i don't know what to do with this , how or what to modify
4c. 'e': highlight an option and select it. did this, but again-- i don't konw what or how to edit it

under that 'e' option, i have the following text-- i'm curious about the "ro root" part- which i suspect may be in error (it just seems "weird" to have ro root i think)?
Code:
## copied from the GRUB> prompt:
kernel /vmlinuz-2.6.17-1.2157_FC5 ro root=
/dev/VolGroup00/LogVol00 rh initrd /initrd-
2.6.17-1.2157_FC5.img
and that's all i've got. i'm grateful for your help if you have anything to lend to me resolving this problem. thanks!
 
Old 09-18-2006, 12:32 AM   #2
xode
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You might want to put another hard drive in your computer, install a clean system to that and then try to recover your data by mounting the original hard drive partitions to, say, /tmp/hdrecover_i, where "i" is a number corresponding to the partition being mounted.
 
Old 09-19-2006, 04:19 AM   #3
WhatsOnYourBrain
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Thanks so much for your reply, xode!! (actually, i did that first thing upon losing access. fortunately, i had access to a few HDD's lying around)

it occurred to me: if i switched from my "home-user" to root as "su --" when i was in /usr/bin/ for the purpose of renaming a directory, and subsequently i entered the following, thinking i was still in the /usr/bin directory (a dumb-time-for-a-shortcut i've learned)
Code:
## i was trying to rename my mozilla directory. 
## after being denied permission to make a directory under /usr/bin/ as "home-user", 
## i decided to go sudo style, and this is where my nightmare began 
## take note of my location in the Filesystem at these points. "?" means i don't know
## which for certain, but i think it was either /usr/bin/ OR / 
####

user@localhost bin]$ su --
Password: xxxxx
[root@localhost ?]# mkdir /usr/bin/mozilla-1.7.13/
[root@localhost ?]# mv ./mozilla* ./*
if i went to /root/ instead of /usr/bin/ and exectued "mv ./*", then DID I CHANGE THE ENTIRE FILESYSTEM to be named "mozilla" by the end of that second line where i used the asterisk??

EDIT: this additional info describes my discovery today that all of the directories are still there, and how i saw them.

if my assumption is correct, i still face the problem of fixing it-- how to "rename the filesystem". maybe i can do it as you've suggested, xode, and just mount the drive? i don't know how these type of things work in Linux (but this is a good learning experience!!). what software do i use to "mount" it? the LVM? command line? a shell script similar to what i've done to mount NTFS drives perhaps?

Looking at my screen capture, how does "uninitialized" compare with "unmounted"?

i'm not afriad to tweak on this-- as long as i know my "barriers", so i don't ruin something. (ie. whatever you do, just don't _______ and your data will remain intact.)

Last edited by WhatsOnYourBrain; 09-19-2006 at 04:57 AM.
 
Old 09-19-2006, 09:46 AM   #4
stress_junkie
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Just a note on su:

When you execute su you will log in to the root account but remain in the same directory that you started.
Code:
su
When you execute su - you will log in to the root account, execute all of root's login scripts, and end up in root's home directory with root's environment such as environment variables.
Code:
su -
The same rules apply if you specify a user account name in the su command.
Code:
su <username>
su - <username>

Last edited by stress_junkie; 09-19-2006 at 09:47 AM.
 
Old 09-19-2006, 11:00 AM   #5
WhatsOnYourBrain
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Quote:
Originally Posted by stress_junkie
When you execute su - you will log in to the root account, execute all of root's login scripts
i know about the folder changes, but what do you mean "execute all of root's login scripts? -- and how is the result uniquely different? (or how does it impact this scenario?)

but-- yeah, this goes w/ what i was saying right?

to summarize, just in case i'm confusing my threads here (and maybe i haven't said..): i'm uncertain if i was " su ", or "su -", and furthermore, uncertain of the exact commands exectued at the CLI. the former bears upon my uncertainty of the third factor-- being "which directory was i in when i did "mv ./*"

what then is at issue here really? i've gone off in directions-- i want to make clear all i'm trying to figure out-- no matter how it happened, whatever-- is this:

1.) i'm getting a Kernel Panic at login. i'm inexperienced, and therefore don't know what are my options in this situation (rendering many valuable documents unretrievable) because of my inability to proceed w/ a recovery process.
2.) from what i've read, mine is not a typical "Kernel Panic" situation due to the cause of it (in fact, no where have i seen anyone describe theirs as
Quote:
Originally Posted by pre-Kernel-load
WARNING: Can't Access (null)
exe of init ((null)) failed Bad Address
although that doesn't mean it's that much different necessarily-- but the "Null" is what i haven't seen, and my concern cause null typically means "nothing where i was expecting something".
3.) i can see that drive as shown in the screen cap. and i browsed it w/ the Fedora Rescue CD-ROM shell commandline (which looked something like "sh#:" and where i executed "sh#: linux rescue" and commenced browsing the device, down through my familiar folders)

knowing 1,2, and 3-- assuming this looks like a situation in which i will be able to proceed-- how do i "Mount" it safely in an attempt to "browse it" from w/in X Windows where i feel comfortable tweaking / moving files, etc, or as xode suggests, just copy it over to another folder (an action i presume is as i have done w/ a multi-partitioned NTFS Win32 drive slaved: /mnt/windows1/ and /mnt/windows2/)

i mean-- saying "Yo! Just mount it, chumpy!" is one thing, and that's awesome and i appreciate it-- but-- i'm hoping someone will tell me how is it done? what software? anything to expressly avoid, or include? etc. that i would greatly appreciate. i'm almost there-- i can feel it. i just want to remain patient so i don't screw it up by trying before i know.


or in "blues-man" speak, it might be:
"Yo, BB.. it's easy-- just grab a Bbm7 on those turnaround changes"
"Ha! B.B. Don't know no chords! you gonna have show me!"

Last edited by WhatsOnYourBrain; 09-19-2006 at 11:03 AM.
 
  


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