Solved: Lost root password - no method works

[apeshansky]

Hi,
I am trying to reset root password on Gentoo box (that I did not setup). I tried adding

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real_init=single

to GRUB kernel line, but then I get

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Give root password for maintenance (or type Control-D to continue):

I also tried adding
real_init=/bin/bash (/bin/sh is a symlink to /bin/bash), real_init=/bin/bb and real_init=/bin/busybox (these are the only shells I see in /bin), but this just is ignored and system starts with runlevel 3. I also tried init=, but this is simply ignored.
I tried to boot from LiveCD (minimal CD), but any attempt to

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chroot /mnt/gentoo /bin/bash

gives

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chroot: cannot run command '/bin/bash': No such file or directory

I suspect this is because the computer has (misconfigured) RAID and so cannot mount /root. When I tried to manually mount /dev/sda3, I get
mount: unknown filesystem type 'linux_raid_member'
message, also fdisk shows /dev/sd[ab] all different sizes and type 83 Linux instead of expected fd raid autodetect. When the system boots, I do see messages about RAID (with some complains about degradation; I'll address these once I can get root access).

As I see it, I have a couple of options left (unless some kind soul here will help me to get it boot single w/out root password ):

• Try to mount RAID in live CD and edit /etc/passwd
• Try to copy all custom PHP/shell script code and Postgres database (backups? What backups? ) using user-level account, reinstall Gentoo, recreate custom software

So any wise words?

[xaviermiller]

Hello,

Did you tried booting an other linux (liveCD/USB), then chroot that partition, then change the password ?

[apeshansky]

Hello,

Did you tried booting an other linux (liveCD/USB), then chroot that partition, then change the password ?

Yes, I did - same problem: cannot mount existing / with message
mount: unknown filesystem type 'linux_raid_member'

I also forgot to mention that there is no sudo on the box.

[rh1]

What LiveCd did you try? Maybe it doesn't have raid support? How about using systemrescuecd which i'm sure has raid/lvm,ect.. support on it.

[jburns]

Did you try adding the word single to the end of the kernel line instead of real_init=single.

[apeshansky]

What LiveCd did you try? Maybe it doesn't have raid support? How about using systemrescuecd which i'm sure has raid/lvm,ect.. support on it.

I used Gentoo minimal install CD (and also full Ubuntu desktop CD). Both do have RAID support (I even did

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modprobe raid[01]

to ensure that modules load), but if I understand this correctly, need some information to mount RAID. (But what do I know - I am just a n00b, so I am asking my betters )

I do have user-level access to the box I need to get in, so if the information is there somewhere, I'll get it (provided it is world-readable).

Thanks.

[NeddySeagoon]

apeshansky,

Press e at the grub menu and add

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init=/bin/bash

to the kernel line, or change it to that if there is an init= statement.
Then boot.

It will come up with just the root filesystem, and the kernel and nothing else. You will be root.
run

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/bin/passwd

you need to use full pathnames as there is no environment set.

Shutdown with

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/sbin/shutdown -h now

[apeshansky]

Did you try adding the word single to the end of the kernel line instead of real_init=single.

Yes; it is ignored, and the box boots into runlevel 3.

Thanks.

[apeshansky]

apeshansky,

Press e at the grub menu and add

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init=/bin/bash

to the kernel line, or change it to that if there is an init= statement.

A-ha! There was

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init=linuxrc

(or some such - the box is at the different location) parameter, but I did not touch it, hoping additional init= down the line will override it. I'll try this.
Thank you.

[NeddySeagoon]

apeshansky,

Oh dear, you need to be at the console to do that, as no services are started.

[apeshansky]

apeshansky,

Oh dear, you need to be at the console to do that, as no services are started.

Yes, of course. I meant "as soon as I get my hands on this sucker "

[apeshansky]

apeshansky,

Press e at the grub menu and add

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init=/bin/bash

to the kernel line, or change it to that if there is an init= statement.
Then boot.

It will come up with just the root filesystem, and the kernel and nothing else. You will be root.
run

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/bin/passwd

you need to use full pathnames as there is no environment set.

Shutdown with

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/sbin/shutdown -h now

Well, what would you know: this did not work either.
Caveat: I was not at the console, but I believe the guy I talked to did everything properly. I had him to do it twice with written keypress-by-keypress instructions and me on the phone.

The system started at runlevel 3 with normal login prompt.

The original grub parameters are:

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kernel /kernel-genkernel-x86_64-2.6.17-gentoo-r8 root=/dev/ram0 init=/linuxrc ramdisk=8192 real_root=/dev/evms/root doscsi doevms2
initrd /initramfs-genkernel-x86_64-2.6.17-gentoo-r8

Any ideas? Please? Pretty please with sugar on top?

[NeddySeagoon]

apeshansky,

Ah, ok - passing parameters to the initrd is doomed to fail. It won't have bash.

Using init=/bin/bb or init=/bin/busybox will get you a root shell in the initrd.
What you can do from there is fairly limited. You should be able to mount root but its much harder.

Its easier to boot a CD that hass all the bits you need to miunt the root filesystem.
Boot normally then

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df -T

will tell you the filesystems in use, in case you have a rare one, like rieser4.

Oh ... you have root on evms. (real_root=/dev/evms/root), so its not simple at all

[apeshansky]

apeshansky,

Ah, ok - passing parameters to the initrd is doomed to fail. It won't have bash.

Using init=/bin/bb or init=/bin/busybox will get you a root shell in the initrd.

Sorry, this did not work either (see my original message). Unless I need to add

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init=/bin/bb

to initrd line? I only tried parameters in kernel line.

What you can do from there is fairly limited. You should be able to mount root but its much harder.

Its easier to boot a CD that has all the bits you need to mount the root filesystem.
Boot normally then

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df -T

will tell you the filesystems in use, in case you have a rare one, like rieser4.

Oh ... you have root on evms. (real_root=/dev/evms/root), so its not simple at all

Don't I know that!
I think the only way short of reinstalling is to manually enter commands needed to mount root from liveCD prompt, but where are these commands? Some configuration file on the box?
I suspect that just adding "doscsi doevms2" to liveCD boot won't help - will it?

[NeddySeagoon]

apeshansky,

It might. look at the help on the liveCD boot screen. I don't remember if the liveCDs ever supported evms.

It looks like they did/do. This wiki page looks useful.
Be careful you do not do any steps that are destructive to your data.

Googling for

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 evms +gentoo

finds other hits too. I have never used evms myself.

[apeshansky]

apeshansky,

It might. look at the help on the liveCD boot screen. I don't remember if the liveCDs ever supported evms.

It looks like they did/do. This wiki page looks useful.
Be careful you do not do any steps that are destructive to your data.

Googling for

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 evms +gentoo

finds other hits too. I have never used evms myself.

OK, I did it!
For the posterity:
1. Boot from live CD; select

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gentoo-nofb doscsi doevms2

to activate evms.
2. Once in, start evms in command mode

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evms

3. Answer "no" (default) to the question about volume <something>
4. Give evms command to mount your root volume (in my case /dev/evms/root) as

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Mount: /dev/evms/root, /mnt/gentoo

5. Exit evms with exit or quit.
6. Do

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chroot /mnt/evms /bin/bash

and change root password.
That did it!

[mokia]

I know. The topic is masked as solved, but I have the same problem for a while.
kernel hanged, and asked the root password.

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Give root password for maintenance (or type Control-D to continue):

type root password, and its not working.

It was a keymap problem.
kernel used the en qwerty
and my system default was hu qwertz
so z y numbers and special characters are not on the right place.
After typing root password in qwery-s geometry the system let me in.

[apeshansky]

I know. The topic is masked as solved, but I have the same problem for a while.
kernel hanged, and asked the root password.

Code: Select all

Give root password for maintenance (or type Control-D to continue):

type root password, and its not working.

It was a keymap problem.
kernel used the en qwerty
and my system default was hu qwertz
so z y numbers and special characters are not on the right place.
After typing root password in qwery-s geometry the system let me in.

Well, I am pretty sure my problem was quite different. To recap: root password unknown, boot used initframs, so all

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init=/bin/bash

(or other shell) parameters in grub where ignored,

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real_init=/bin/bash

brought same prompt for root password, and attempts to mount existing root while booted from CD were rejected because of use of evms (LVM).
I am pretty sure I saw another thread with the same problem the quoted poster was having.

[mokia]

Well i'm only replied to this topic

in the hope that it will be useful

In future for someone.
For gogling and searching users.

So sorry, but my attention was fixed on "Give root password for maintenance (or type Control-D to continue):"
And simply swapped in my mind "unknown" wit "not working"
Pls excuse my mistake.

[cwr]

The easiest way I've found to reset the root password is to boot off a CD,
mount the / partition, and edit the relevant /etc/passwd to remove the
first 'x' in root's entry. Then boot normally and log in _without_ a root
password, and reset the password from there.

Will