/etc/passwd

[Thomas Kopp]

Hi,
If you change the entry for the root-shell in /etc/passwd to ksh, is there a possiblity to log into the machine via root account?? ( In moment I got the error message "no shell" )
Thanks
Thomas

[James R. Ferguson]

Hi:

Do *NOT* change root's default shell. It should always be /sbin/sh ( the POSIX shell ).

During startup, only "/" is initially mounted, not /usr, etc. in which shells like 'ksh' live.
Furthermore, /sbin/sh is devoid of any linkages to libraries in /usr.

...JRF...

[Stefan Farrelly]

If you change root's entry to ksh then yes, youre in trouble if you boot in single user mode as /usr is not mounted and this is where ksh lives, and the libraries needed for it.

Leave it as /sbin/sh which is statically linked so it doesnt need any libraries (and thus /usr)

[A. Clay Stephenson]

I would add one other thing, whenever you are making any direct changes to the passwd file (and especially the root entry), be logged in as root in two sessions so that you can get yourself out of trouble as fast as you got yourself in.

Clay

[James R. Ferguson]

Hi again:

...and I'd second Clay's comment!

Also, 'vipw' is another useful caution when editting /etc/passwd.

...JRF...

[Thomas Kopp]

Anyway you allare right, but now the /etc/passwd
is changed.
Is there still a way to get into the machine to change this entry back ??
Thomas

[Steffi Jones_1 · Accepted solution]

Hello Thomas,

I guess you got the message that you can't change it to ksh. If you did this already and need to know a way out of this now then you have to go and boot from the support cd and move the default /etc/passwd in place. After you get the box back up you can move the old passwd file back in place and edit it back to /sbin/sh.

Unfortunally this is a situation where booting into single user mode won't help either, because it won't find the shell for that.

Good luck,

Steffi Jones

[Vincenzo Restuccia]

boot in single user mode

[Thomas Kopp]

Hi Steffi,
do you mean the HP-Ux Support Plus ... CD
or the installation CD for HP-Ux 11.00.
Thanks
Thomas

[John Bolene]

Leave root alone, don't change that shell.

Also the entry must be the first one in the file or it will not be found.

We had an admin that sorted the passwd file to make it look better and then the box went stupid.

[Thierry Poels_1]

hi,
you don't have 2nd root user in your /etc/passwd?? Would come in handy in this situation!
good luck,
Thierry.

[Rick Lui]

Hi,
I had this problem once and this is the reply from my local HP support. Never got to try it though cos I managed to restore the file from a network backup. Maybe the forum's experts can comment:

You need to boot as single user mode. To boot to single user mode, during
boot up sequence,

-interrupt the boot process within the 10 sec.
-Choose Y, to Interact with ISL
#BO PRI (or the correct path of your local primary hdd)
#hpux -is (launch hp-ux in single user mode)

#mount /usr and /var (mount the necessary file system)
#vipw (to change the shell in /etc/passwd)