SARK V4.0.0 Password
Changing the Browser Password
For security reasons, we recommend that you change the default browser password immediately after installation using the change password panel. The system requires a password of at least 8 characters and you should try to use a mixture of upper and lower case and at least one numeric character. The change password panel will change the browser password ONLY. It will not change the root password of the box.
Changing the root password on SME based systems
For the x86 based SARK systems running under SME server the root password can be changed by visiting the to the SME Server Linux platform administration app. You can connect to it using
https://sarkserver-ip-address/server-manager
Documentation for SME server can be found on the SME server Wiki at
http://wiki.contribs.org/SME_Server:Documentation
Changing the root password on embedded systems (SARK200 and SARK500)
The root password can be changed by establishing an SSH console session with the unit and issuing the linux passwd command. The format of the command is as follows
PASSWD(1) User Commands PASSWD(1)
NAME
passwd - change user password
SYNOPSIS
passwd [options] [LOGIN]
DESCRIPTION
The passwd command changes passwords for user accounts. A normal user may only change the
password for his/her own account, while the superuser may change the password for any account.
passwd also changes the account or associated password validity period.
Password Changes
The user is first prompted for his/her old password, if one is present. This password is then
encrypted and compared against the stored password. The user has only one chance to enter the
correct password. The superuser is permitted to bypass this step so that forgotten passwords may
be changed.
After the password has been entered, password aging information is checked to see if the user is
permitted to change the password at this time. If not, passwd refuses to change the password and
exits.
The user is then prompted twice for a replacement password. The second entry is compared against
the first and both are required to match in order for the password to be changed.
Then, the password is tested for complexity. As a general guideline, passwords should consist of
6 to 8 characters including one or more characters from each of the following sets:
· lower case alphabetics
· digits 0 thru 9
· punctuation marks
Care must be taken not to include the system default erase or kill characters. passwd will
reject any password which is not suitably complex.
Hints for user passwords
The security of a password depends upon the strength of the encryption algorithm and the size of
the key space. The legacy UNIX System encryption method is based on the NBS DES algorithm. More
recent methods are now recommended (see ENCRYPT_METHOD). The size of the key space depends upon
the randomness of the password which is selected.
Compromises in password security normally result from careless password selection or handling.
For this reason, you should not select a password which appears in a dictionary or which must be
written down. The password should also not be a proper name, your license number, birth date, or
street address. Any of these may be used as guesses to violate system security.
You can find advices on how to choose a strong password on
http://en.wikipedia.org/wiki/Password_strength
OPTIONS
The options which apply to the passwd command are:
-a, --all
This option can be used only with -S and causes show status for all users.
-d, --delete
Delete a user's password (make it empty). This is a quick way to disable a password for an
account. It will set the named account passwordless.
-e, --expire
Immediately expire an account's password. This in effect can force a user to change his/her
password at the user's next login.
-h, --help
Display help message and exit.
-i, --inactive INACTIVE
This option is used to disable an account after the password has been expired for a number of
days. After a user account has had an expired password for INACTIVE days, the user may no
longer sign on to the account.
-k, --keep-tokens
Indicate password change should be performed only for expired authentication tokens
(passwords). The user wishes to keep their non-expired tokens as before.
-l, --lock
Lock the password of the named account. This option disables a password by changing it to a
value which matches no possible encrypted value (it adds a ´!´ at the beginning of the
password).
Note that this does not disable the account. The user may still be able to login using
another authentication token (e.g. an SSH key). To disable the account, administrators should
use usermod --expiredate 1 (this set the account's expire date to Jan 2, 1970).
Users with a locked password are not allowed to change their password.
-n, --mindays MIN_DAYS
Set the minimum number of days between password changes to MIN_DAYS. A value of zero for this
field indicates that the user may change his/her password at any time.
-q, --quiet
Quiet mode.
-r, --repository REPOSITORY
change password in REPOSITORY repository
-S, --status
Display account status information. The status information consists of 7 fields. The first
field is the user's login name. The second field indicates if the user account has a locked
password (L), has no password (NP), or has a usable password (P). The third field gives the
date of the last password change. The next four fields are the minimum age, maximum age,
warning period, and inactivity period for the password. These ages are expressed in days.
-u, --unlock
Unlock the password of the named account. This option re-enables a password by changing the
password back to its previous value (to the value before using the -l option).
-w, --warndays WARN_DAYS
Set the number of days of warning before a password change is required. The WARN_DAYS option
is the number of days prior to the password expiring that a user will be warned that his/her
password is about to expire.
-x, --maxdays MAX_DAYS
Set the maximum number of days a password remains valid. After MAX_DAYS, the password is
required to be changed.
CAVEATS
Password complexity checking may vary from site to site. The user is urged to select a password
as complex as he or she feels comfortable with.
Users may not be able to change their password on a system if NIS is enabled and they are not
logged into the NIS server.
passwd uses PAM to authenticate users and to change their passwords.
FILES
/etc/passwd
User account information.
/etc/shadow
Secure user account information.
/etc/pam.d/passwd
PAM configuration for passwd.
EXIT VALUES
The passwd command exits with the following values:
0
success
1
permission denied
2
invalid combination of options
3
unexpected failure, nothing done
4
unexpected failure, passwd file missing
5
passwd file busy, try again
6
invalid argument to option
