After Hours

Wacky Linux Part 9: Sidestepping permissions

In our last episode, I had just finished installing Ubuntu 5.10 on my Compaq Armada M300, and had backed myself into a boot parameter catch-22, and sought help from Tech Q&A.

Well, with some clues from my helpful friends in the TR community, I

managed to patchwork together a rather crude solution to the problem.

Strap in, it's a long and winding road...

1) I could hit [ESC] during the boot process and get

to a GRUB editor, which let me remove the vga=771

parameter for

the current boot. This got me into a healthy GUI session. The problem

was that I had to do this for every boot, because the change isn't

permanent. Thanks to member mparic for pointing me to,

which got me this far. Unfortunately, I had to find the file that

dictated these boot parameters and permanently alter it, which a GUI

made easier, what with the visual file-surfing and all.

2) I perused the local help file and found what

I was looking for. The file I needed to modify was

/boot/grub/menu.lst. The problem was that this is a Read-Only file, at

least from the GUI. I could clearly see where the vga

parameter was specified,

but I wasn't sure how to change file permissions from within the

GUI. In all likelihood, this couldn't be done, since the GUI opens under

my user session, not a root session. I dropped to a terminal with

[CTRL][ALT][F1]—thanks for the tip, jmgarvin—and tried to switch to root as Jaqui had taught me (simply type su to switch users and the system will assume you mean root) but here's where Ubuntu really started to cheese me off...

3) Ubuntu demands a password for root access, and I know for a fact I

was never prompted to specify this during the install process. If

there's a root password, I don't know it. The /boot/grub/menu.lst file

is owned by root, so I must become root to unlock it. The solution to

this was to boot into recovery mode—again, interrupting GRUB during

the boot process by hitting [ESC]—which opens at the command line,

logged in (without a password prompt) as root. From there, I simply did

a little cd /boot/grub/menu.lst followed by chmod 002 menu.lst, followed by reboot. I intended to edit menu.lst from the GUI.

4) Turns out, I still didn't have permission to edit the file as jay and not root, so I repeated all the above steps but with a chmod 007. This did give me permission, but the GUI had no native editor for a .lst file.

5) I jumped to a terminal session from the GUI, and tried to use vi to edit the file, as Jaqui suggested. I found vi very incomprehensible, but msimko suggested pico

as a substitute, and it has friendly commands listed at the bottom of

its text editor, so that was helpful. I was finally able to edit the

menu.lst file and save my changes. From there, it required a

[CTRL][ALT][DEL] to reboot (the reboot command only works from root). The changes worked.

6) To keep things clean, I rebooted into recovery mode (AKA root) and restored the menu.lst file's original permissions with a chmod 700. At least, I think I did; if anybody wants to tell me different, I'd appreciate it.

So, to be clear, it has taken me nine different blog sessions to get a

full, clean, stable install of Ubuntu, due largely to some quirky video

driver issues (it happens) and the fact that I can't easily obtain root

access on my own machine (this is unacceptable).

So, our next project (and my next Tech Q&A question, worth 500 useless TechPoints): How do I find out the root password on my own Ubuntu Linux machine?


Keep up with the Trivia Geek's ongoing Wacky Linux Adventures with the wackylinux tag. If it doesn't say wackylinux, it's not really a wacky Linux adventure.


Jay Garmon has a vast and terrifying knowledge of all things obscure, obtuse, and irrelevant. One day, he hopes to write science fiction, but for now he'll settle for something stranger — amusing and abusing IT pros. Read his full profile. You can a...

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