[comp.unix.questions] passwd file corrupted

vanmane@sumax.UUCP (Mohan Vanmane) (06/27/89)

I have a Convergent Tech miniframe running unix system V.
Last thing I did on the system was change the root password (while
I was logged in as root).

Since then no one can login.  System seems to be running fine.  I reset the
system and it boots up fine. File system is OK and the system comes up
in multiuser mode.

How can I bring this machine down to administrative mode so that I can
change the password file?

I appreciate any help to solve this problem.

Thank you.


vanmane%sumax.uucp@beaver.cs.washington.edu

dold@mitisft.Convergent.COM (Clarence Dold) (06/27/89)

in article <664@sumax.UUCP>, vanmane@sumax.UUCP (Mohan Vanmane) says:

> I have a Convergent Tech miniframe running unix system V.
> Last thing I did on the system was change the root password (while
> I was logged in as root).

> How can I bring this machine down to administrative mode so that I can
> change the password file?

How can I tell, via news, whether this is a legitimate request from an
authorized System Administrator, or a joke from an 'Intro to UNIX' student
that has a bet with his teacher that he can break into the system?
-- 
---
Clarence A Dold - dold@tsmiti.Convergent.COM		(408) 434-5293
		...pyramid!ctnews!tsmiti!dold
		P.O.Box 6685, San Jose, CA 95150-6685	MS#10-007

stripes@wam.UMD.EDU (06/28/89)

In article <664@sumax.UUCP> vanmane@sumax.UUCP (Mohan Vanmane) writes:
[stuff deleted]
>How can I bring this machine down to administrative mode so that I can
>change the password file?
>
>vanmane%sumax.uucp@beaver.cs.washington.edu
Since nobody else can get on you don't need to go into single user mode :-)
If it makes you feel better I beleve it's "init 1", but you don't need to
be in single-user mode to safely edit the passwd file.
There should be a /etc/vipw that will let only one person edit /etc/passwd,
provided they all use /etc/vipw (or /etc/lockpw & /etc/unlockpw).  If for
some reason you don't have thoes just make shure nobody else, and nothing else
edits the file while you do.  (and yes the shurest you can be in in single
user mode).  Also if you system has shadow password file support (and you
are useing it) to check the shadow password file (where ever it is).
-- 
           stripes@wam.umd.edu          "Security for Unix is like
      Josh_Osborne@Real_World,The          Mutitasking for MS-DOS"
      "The dyslexic porgramer"                  - Kevin Lockwood
    "A career is great, but you can't run your fingers through it's hair"

sid@friday.rtech.COM (Sid Shapiro) (06/28/89)

In article <8906271706.AA22357@cscwam.UMD.EDU> stripes@wam.UMD.EDU writes:
>In article <664@sumax.UUCP> vanmane@sumax.UUCP (Mohan Vanmane) writes:
>[stuff deleted]
>>How can I bring this machine down to administrative mode so that I can
>>change the password file?
>>
>>vanmane%sumax.uucp@beaver.cs.washington.edu
>Since nobody else can get on you don't need to go into single user mode :-)

I'd say that he doesn't know the root passwd so he can't change it
without being logged in as root, but since he doesn't know it the only
way to do it is to go into single user.

There should be a keyswitch on the fron of the machine.  Turn it off,
then to "remote" (it may not be "remote", but normally it turned
clockise as far as it can go.  Turn off, then back on such that it is
one click to the counter-clockwise of normal.)  This will bring you up
in "administrative" mode (single user in ct-ese).  You will probably
have to figur out where the real root is and mount it, then you can
edit the passwd file.

Good luck - those machines are a bitch.
/ Sid /

rhealey@umn-d-ub.D.UMN.EDU (Rob Healey) (06/29/89)

In article <747@mitisft.Convergent.COM> dold@mitisft.Convergent.COM (Clarence Dold) writes:
>in article <664@sumax.UUCP>, vanmane@sumax.UUCP (Mohan Vanmane) says:
>> How can I bring this machine down to administrative mode so that I can
>> change the password file?
>
>How can I tell, via news, whether this is a legitimate request from an
>authorized System Administrator, or a joke from an 'Intro to UNIX' student
>that has a bet with his teacher that he can break into the system?

	If the person in question can get to the power switch to bring the
	machine into administration mode then all the software security is
	pretty much moot. Also, the quickest way to fix things up would
	be to fire up the original installation/distribution tape and go
	into "maintainance" mode. Once in maintainance mode you can mount
	/ and edit the password file. Of course one needs to find that
	original installation tape/disk that's hiding in some mysterious
	dark corner...

			-Rob Healey

dold@mitisft.Convergent.COM (Clarence Dold) (06/29/89)

in article <1127@umn-d-ub.D.UMN.EDU>, rhealey@umn-d-ub.D.UMN.EDU (Rob Healey) says:

> 	If the person in question can get to the power switch to bring the
> 	machine into administration mode then all the software security is
> 	pretty much moot. Also, the quickest way to fix things up would
> 	be to fire up the original installation/distribution tape and go
> 	into "maintainance" mode. Once in maintainance mode you can mount
> 	/ and edit the password file. Of course one needs to find that
> 	original installation tape/disk that's hiding in some mysterious
> 	dark corner...

I started to mail a reply, when I realized that Washington University was 
one of the recipients in a 'University Gift Program' where we gave away
several hundred MiniFrames.
Two of the reasons we gave them away:
10 Mhz 68010 wasn't state of the art anymore.
These models were Floppy only, couldn't be upgraded to QIC.

If this is a floppy only system, he is pretty much out of luck.
The disk could be added as drive one to another machine, and mounted,
or he could back up what he can, and then 'clone' the disk via
the Diagnostics across the 'cluster' a proprietary LAN.

-- 
---
Clarence A Dold - dold@tsmiti.Convergent.COM		(408) 434-5293
		...pyramid!ctnews!tsmiti!dold
		P.O.Box 6685, San Jose, CA 95150-6685	MS#10-007