...it seems that changes in /share/flash/data/etc/passwd are persistent. (If I'm not totally mixing off something right now.) -GreenBear?, 26.08.2008 On my machine, this is a link to /share/flash/conf/passwd -dbh 2009-02-09

...it seems that changes in /share/flash/data/etc/passwd are persistent. (If I'm not totally mixing off something right now.) -GreenBear?, 26.08.2008

On firmware version V2.3R63-uNSLUng-6.10-beta...

...it seems that changes in /share/flash/data/etc/passwd are persistent. (If I'm not totally confused, right now) -GreenBear?, 26.08.2008

So, you've got Unslung installed and now you'd like to change the root password to something of your own choosing. Well, the /bin/unsling script from InstallUnslungFirmware will ask you for a new root password when you first unsling a disk. But what if you want to change the root password later, or change other passwords than root?

You change the password with the passwd utility, but when the NSLU2 reboots, it goes back to the default root passwd and you're left scratching your head wondering what went wrong.

Overview

Scripts to simplify the job

Alternative: edit the persistent passwd file directly

There's more than one way to skin a cat. You can also access the NSLU2 disk from Linux, and edit the file in the "conf" partition named /passwd. This is the file which on the NSLU2 becomes /share/hdd/conf/passwd. It is a normal Linux /etc/passwd format file. The simplest operation is to copy the encrypted password from one user's entry to another.

for me it works, mike 22.06.06

An alternative:

The boot sequence for 6.8 is rc.sysinit -> rc.1, which calls rc.reset_usrgrpshare. rc.reset_usrgrpshare calls /usr/sbin/reset_ugs which replaces the /etc/passwd file with one from memory.

rc.reset_usrgrpshare is:

(:table border=0 width=100% bgcolor=#f0f8ff:) (:cell:)

 
#!/bin/sh

if ( [ -f /unslung/rc.reset_usrgrpshare ] && . /unslung/rc.reset_usrgrpshare ) ; then return 0 ; fi

/usr/sbin/reset_ugs;
 

(:tableend:)

The problem can be fixed by:

1. Copy /etc/passwd to /opt/etc/passwd (which will not be overwritten). Remember to do this after any changes to passwords or users or 'cp /etc/passwd /opt/etc/passwd' can be added to rc.reboot and rc.halt.

2. Create /unslung/rc.reset_usrgrpshare like so:

(:table border=0 width=100% bgcolor=#f0f8ff:) (:cell:)

 
#!/bin/sh

/usr/sbin/reset_ugs

cp /opt/etc/passwd /etc/passwd;
 

(:tableend:)

 find / -name .htpasswd

Question: Is the script above still true for the Unslung 6.8?

for me it works, mike 22.06.06

Question: Is the script above still true for the Unslung 6.8?

There are generally 3 disks to worry about

Too many files, not enough neurons for me to keep it straight...

Here is a more intelligent script. This one will:

• Preserve the symbolic link
• Update all known copies of the passwd file
• Handle any number of arguments for the passwd command
• Update all secondary files without running the passwd command. Useful if you edit /etc/passwd to change a shell.
• Handle errors if the passwd command fails

To use, install as /opt/bin/spasswd (chmod +x, of course).

/opt/bin/spasswd --help will provide usage.

If someone who knows the current boot flow wants to resolve the open issue - re-generating the symlink based on the boot device if /etc/passwd starts out as a regular file - please do. (And let me know.)

This seems to work on V5.5-beta.

Read and obey the previous cautions, and enjoy.

--tlhackque

(:table border=0 width=100% bgcolor=#f0f8ff:) (:cell:)

 
#!/bin/sh
#
# /bin/spasswd - manage /etc/passwd and its aliases
#
# tlhackque
#
# Parse command switches.  Musn't conflict with /usr/bin/passwd.
#
if [ "($1)" = '(--verbose)' ]; then
   VERBOSE=y
   shift
else
   VERBOSE=
fi
#
# Determine if /etc/passwd starts out as a symlink
#
if [ -L /etc/passwd ]; then
  INITIALPW=`ls -l /etc/passwd | sed -e 's|.*/etc/passwd -> \(/share/.*/conf/passwd\)$|\1|'`
  if [ "$VERBOSE" != '' ]; then echo "/etc/passwd -> $INITIALPW" ; fi
else
  INITIALPW=/etc/passwd
fi
#
if [ "($1)" != "(--refresh)" ]; then
  if [ "($1)" = "(--help)" ]; then
    cat <<EOF
Usage: $0 [--verbose] passwd_command_arguments
       $0 [--verbose] --refresh
       $0 --help

If --verbose is present, verbose output is produced for
reassurance (or debug).

The first format executes the /usr/bin/passwd command with
the specified arguments (if any).  If the command succeeds,
it then locates the other copies of the /etc/passwd file
and updates them by copying the new /etc/passwd file over
them.

The second format refreshes the copies, but does not
execute /usr/bin/passwd.  Use this after any manual
edits to /etc/passwd.  Be sure to use an editor that
preserves symbolic links, or edit the target!

The third format displays this message.

Issues:
  Perhaps /etc/passwd should be set to the appropriate
  symbolic link if it starts out as a regular file.
EOF
    exit
  else
    /usr/bin/passwd $* || exit
   # /etc/passwd has been updated, and probably is not a symlink.
  fi
fi
#
# /etc/passwd may be a symlink to the real file
#
if [ -L /etc/passwd ]; then
  ACTIVEPW=`ls -l /etc/passwd | sed -e 's|.*/etc/passwd -> \(/share/.*/conf/passwd\)$|\1|'`
else
  ACTIVEPW=/etc/passwd
fi
#
if [ "$VERBOSE" != '' ]; then echo "Updated $ACTIVEPW" ; fi
#
# Used when booting from disk 1
#
if [ -n "`mount | grep /share/hdd/conf`" ]; then
  if [ "$ACTIVEPW" != "/share/hdd/conf/passwd" ]; then
     cp /etc/passwd /share/hdd/conf/passwd
     if [ "$VERBOSE" != '' ]; then echo "Updated /share/hdd/conf/passwd" ; fi
  fi
fi
# Used when booting from disk 2
if [ -n "`mount | grep /share/flash/conf`" ]; then
  if [ "$ACTIVEPW" != "/share/flash/conf/passwd" ]; then
     cp /etc/passwd /share/flash/conf/passwd
     if [ "$VERBOSE" != '' ]; then echo "Updated /share/flash/conf/passwd" ; fi
  fi
fi
# Used when no disk present -- cat used because flash FS
# doesn't like cp
if [ "$ACTIVEPW" != "/usr/local/passwd" ]; then
   cat /etc/passwd >/usr/local/passwd
   if [ "$VERBOSE" != '' ]; then echo "Updated /usr/local/passwd" ; fi
fi
#
# If the initial /etc/passwd was a symlink, restore it.
if [ "$INITIALPW" != "/etc/passwd" ]; then
   ln -sf $INITIALPW /etc/passwd
   if [ "$VERBOSE" != '' ]; then echo "Re-linked /etc/passwd -> $INITIALPW" ; fi
fi
# EOF
 

(:tableend:)

Thanks to everyone for their previous efforts.

To change the web admin password from the command prompt try htpasswd. http://www.acme.com/software/thttpd/htpasswd_man.html

Here is the command to find the .htpasswd files to work with. (:table border=0 width=100% bgcolor=#eeffee:) (:cell:)

 cd /;find -name .htpasswd

(:tableend:) Here is the command to edit the admin of a given file. (:table border=0 width=100% bgcolor=#eeffee:) (:cell:)

 htpasswd -c /dir/.htpasswd admin #where dir is the directory found with find

(:tableend:)

My firmware doesn't include htpasswd so i can't test it. A quick fix is to edit a known working file and copy its encrypted password or whole file, however the key changes so this might not work.

Thanks to tman, rwhitby, barabasy69 and jncharli for previous efforts.

To do this for a slug using an Unslung disk plugged into USB port 1, run these commands:

To do this for a slug using an Unslung disk plugged into USB port 2, run these commands:

1. passwd
2. cp /etc/passwd /share/hdd/conf/passwd

To do this for a slug using an unslung disk plugged into USB port 2, run these commands:

1. passwd
2. cp /etc/passwd /share/flash/conf/passwd

 
#!/bin/sh
# 
# slugpasswd - change password on NSLU2 after an unslung disk is attached

# change password 
passwd $1
# copy to unslung disk in port 1
cp /etc/passwd /share/hdd/conf/passwd
# Optionally change the /usr/local copy (not recommended for inexperienced users)
cp /etc/passwd /usr/local/passwd
 

So, you've got Unslung installed and now you'd like to change the root password to something of your own choosing. You change the password with the passwd utility, but when the NSLU2 reboots, it goes back to the default root passwd and you're left scratching your head wondering what went wrong.

The problem here is that the actual passwd file for the NSLU2 is kept in /share/hdd/conf/passwd and /usr/local/passwd. When the NSLU2 boots, whatever file is located at /etc/passwd is overwritten with a symlink to either /share/hdd/conf/passwd (when an unslung disk is attached) or /usr/local/passwd (when not unslung or no disk present).

To do this for a slug using an unslung disk plugged into USB port 1, run these commands:

1. passwd
2. cp /etc/passwd /share/hdd/conf/passwd

(:table border=0 width=100% bgcolor=#eeffee:) (:cell:)

(:tableend:)

(:table border=0 width=100% bgcolor=#eeffee:) (:cell:)

(:tableend:)

Thanks to rwhitby, barabasy69 and jncharli for previous efforts.

1. run passwd to change the password and create a new /etc/passwd file
2. copy the new file at /etc/passwd into the appropriate persistent file

To do this for a slug using an unslung disk plugged into usb port 1, run these commands:

• passwd
• cp /etc/passwd /share/hdd/conf/passwd

1. The passwd file is valid. An invalid file can lock you out of the slug.
2. You are copying into the appropriate location. There are generally 3 disks to worry about, the internal flash, USB port 1, and USB port 2.

So, you've got Unslung installed and now you'd like to change the root password to something of your own choosing. You change the password with the passwd utility, but when the NSLU reboots, it goes back to the default root passwd and you're left scratching your head wondering what went wrong.

The problem here is that the actual passwd file for the NSLU is kept in /share/hdd/conf/passwd and /usr/local/passwd. When the NSLU boots, whatever file is located at /etc/passwd is overwritten with a symlink to either /share/hdd/conf/passwd (when an unslung disk is attached) or /usr/local/passwd (when not unslung or no disk present).

When the passwd utility is used to change your password, /etc/passwd is overwritten with a good passwd file but not the others, and so the changes do not persist after a reboot. In order to change your password from the command line you need to do 2 things:

1. run passwd to change the password and create a new /etc/passwd file 2. copy the new file at /etc/passwd into the appropriate persistent file

To do this for a slug using an unslung disk plugged into usb port 1:

1. passwd
2. cp /etc/passwd /share/hdd/conf/passwd

 #!/bin/sh

When you do this, be absolutely sure about 2 things: 1. The passwd file is valid. An invalid file can lock you out of the slug. 2. You are copying into the appropriate location. There are generally 3 disks to worry about, the internal flash, USB port 1, and USB port 2.

This procedure works in version 5.5-beta. If this stops working in later versions, it may be helpful to search for all locations of passwd:

 cp /etc/passwd /usr/local/passwd 

When the passwd utility is used to change your password, /etc/passwd is overwritten but not the others. In order to change your password from the command line you need to do the following (example is for when using an unslung disk plugged into usb port 1):

See also FAQ nr 7.

 # slugpasswd - change password on NSLU2 after an unslung disk is attached

Note: If you are using an unslung disk, there are a number of steps to perform before this procedure can be followed. You will first have to boot with the disk detached, enable telnet from the web admin, login using telnet, re-attach the disk, then wait for it to mount. This is the same series of steps used to unsling the disk after the firmware is installed, listed in the 'UNSLINGING' DETAILS section of the README file that accompanies the Unslung firmware. (see http://www.toddcomp.com/NSLU2/README.txt)

This procedure works in version 3.18-beta. If this stops working in later versions, it may be helpful to search for all locations of passwd:

Thanks to rwhitby, barabasy69 and jncharli for previous efforts.

Thanks to rwhitby and barabasy69 for previous efforts.

Added by jncharli on 2005 March the 29th

As many users, I experienced some troubles to change the telnet root password when a disk is attached. As an example, the procedure above doesn't work...

Here follows the procedure I found, tested with V2.3R25-uNSLUng-standard-3.18-beta. It supposes that you have installed this release of Unslung.

• Boot your NSLU2 with *NO* disk attached
• Enable Telnet through http://192.168.192.50/Management/telnet.cgi, using default username/password (admin/admin), and clicking "Enable Telnet" if required

     (change 192.168.192.50 by the IP address of your NSLU2)

• Start a Telnet session (telnet 192.168.192.50) as root, using default password (uNSLUng)

     (change 192.168.192.50 by the IP address of your NSLU2)

• Hot plug your disk into your NSLU2
• Wait some minutes in order your disk to be automatically mounted

     As soon as the disk is mounted, the /etc/passwd file is overwritten by the passwd file stored on the mounted disk 

• enter the following commands :
  • passwd

          enter twice your new password for root

• cp /etc/passwd /share/hdd/conf/

          It's useless to create any link

• reboot

That's it !

To check it runs, after the reboot :

• Keep the disk plugged in the NSLU2
• Enable Telnet through http://192.168.192.50/Management/telnet.cgi, using your customized username/password, and clicking "Enable Telnet" if required

     (change 192.168.192.50 by the IP address of your NSLU2)

• Start a Telnet session (telnet 192.168.192.50) as root, using your newly changed password

     (change 192.168.192.50 by the IP address of your NSLU2)

It should run...

The problem here is that the passwd file for the NSLU is kept in /etc/passwd, /usr/local/passwd and /share/hdd/conf/passwd. When the NSLU boots, /etc/passwd is overwritten at boot from either /usr/local/passwd (when not unslung or no disk present), or /share/hdd/conf/passwd (when an unslung disk is attached).

When the passwd utility is used to change your password, /etc/passwd is overwritten but not the others. In order to change your password from the command line you need to do the following (example is for when using an unslung disk):

1. copy /etc/passwd over /share/hdd/conf/passwd
2. create a symlink /etc/passwd to /share/hdd/conf/passwd

 cp /etc/passwd /share/hdd/conf/passwd 
 ln -sf /share/hdd/conf/passwd /etc/passwd

Restoring the symlink is not required to make the password 'stick', but creating it makes sense from the principle of keeping only 1 copy of any information.

Note: I don't know whether /etc/passwd is originally a symlink or a file (seems to depend upon the unslung version), but in either case, this works in current 3.18-beta. If this stops working in later versions, it may be helpful to search for all locations of passwd:

Thanks to rwhitby and barabasy69 for previous efforts.

Update 24-Feb-2005
Maybe, if in doubt, you can run a command like that:

 for P in `find /share/hdd/conf -name passwd`; do ls -la $P; done

...and see what shows up. :)

 #!/bin/sh
 # for unslung-v3.17-beta
 # slugpasswd - change password on NSLU2 and keep /etc/passwd symlink in order

 passwd $1
 cp /etc/passwd /share/hdd/conf/passwd 
 ln -sf /share/hdd/conf/passwd /etc/passwd

Note: I am running with no drives at all so this may not quite apply to a system with a drive attached. Someone with a drive care to test and elaborate? (Worst case if your changes aren't saving do a:

 find / -name 'passwd'

Update 03-Jan-2005
As of v3.17-beta, at least (and possibly earlier versions - I've been away for awhile), the /etc/passwd *is* a real file but it gets overwritten at boot by a copy of what's in /usr/local/passwd (The /passwd mentioned above appears to be gone now).
So when you make a change be sure to copy it over to /usr/local/passwd as well or your change will get undone on the next boot.

Note: I am running with no drives at all so this may not quite apply to a system with a drive attached. Someone with a drive care to test and elaborate? (Worst case if your changes aren't saving do a:

find / -name 'passwd'
\\

[1] http://groups.yahoo.com/group/nslu2-linux/message/1886

=============================== Update 03-Jan-2005 As of v3.17-beta, at least (and possibly earlier versions - I've been away for awhile), the /etc/passwd *is* a real file but it gets overwritten at boot by a copy of what's in /usr/local/passwd (The /passwd mentioned above appears to be gone now).

   So when you make a change be sure to copy it over to /usr/local/passwd as well or your change will get undone on the next boot.

Note: I am running with no drives at all so this may not quite apply to a system with a drive attached. Someone with a drive care to test and elaborate? (Worst case if your changes aren't saving do a:

   find / -name 'passwd'

...and see what shows up. :)

1. delete /etc/passwd with rm (DO NOT do this if you're logged in as a user other than root and using sudo, since this will leave sudo non-functional, and you with no way to create the symlink. Instead, use the "ln -sf" syntax when creating a link in the next step.)

 ln -sf /passwd /etc/passwd

 #!/bin/bash
 # 
 # slugpasswd - change password on NSLU2 and keep /etc/passwd symlink in order

 passwd $1
 cp /etc/passwd /passwd 
 rm /etc/passwd 
 ln -s /passwd /etc/passwd

Thanks to rwhitby for pointing me to the mailing list post[1] and barabasy69 for figuring this out in the first place.

[1] http://groups.yahoo.com/group/nslu2-linux/message/1886

So, you've got Unslung installed and now you'd like to change the root password to something of your own choosing. You change the password with the passwd utility, but when the NSLU reboots, it goes back to the default root passwd and you're left scratching your head wondering what went wrong.

The problem here is that the passwd file for the NSLU is kept in / and /etc/passwd is a symlink to /passwd. When you use the passwd utility to change your password, it removes the symlink in /etc/passwd and writes a new file. In order to change your password from the command line you need to do the following.

1. passwd (change the password)
2. copy /etc/passwd over /passwd
3. delete /etc/passwd
4. create a symlink /etc/passwd to /passwd

Here's a little shell script to take care of all this for you.

#!/bin/bash #

1. slugpasswd - change password on NSLU2 and keep /etc/passwd symlink in order

passwd $1 cp /etc/passwd /passwd rm /etc/passwd ln -s /passwd /etc/passwd

Thanks to rwhitby for pointing me to the mail list posting[1] and barabasy69 for posting this info to the list in the first place.