I think that this behaviour is being caused by the use of a 'while read' loop to drive the 'ssh' command. The way input is read in and processed in this particular script may not actually be what you'd expect. Instead of it looping nicely around, the entirety of your arguments end up being passed to 'ssh' in one glob, and it's just doing the first one.
Maybe try a 'for' loop instead ? So something like:
See if that works, and let us know how you get on.
Hey..
I am new in scripting.. I know a little bit of scripting.. I am facing some problem.. I need to create a script using which I may log on to a server (e.g. ftp) with ID and password.. thus copy a particular file to a local dir.. the commands required to do that I do know.. I am able to do it... (1 Reply)
I am trying to write a script to change passwords for the same user on multiple servers.
My environment runs purely ssh / scp not rsh / rcp and therefore coping using rcp is not an option.
I have been playing with expect to perform tasks but think there must be a better way.
Has anyone got... (7 Replies)
Hi Friends.
I am new to scripting now i want to change the root password using the script with standard password.
which is the easy scripting to learn for the beginner, Thanks in advance. (2 Replies)
Hi,
I am very bad at scripting. I need help from scripting experts...
I need to change password of around 100 linux remote servers. I have been given a script for changing the password that automates the task. however I do not understand the usage and meaning of the script, the script is an... (0 Replies)
Hello Folks
Scenario :
I have a linux box (expect tool installed) which connects to 1000+ other boxes (either Solaris or AIX or Linux ) with a specific id and password using SSH.
I now wish to write a script (Shell and/or expect and/or Python) which will change this existing password to a... (1 Reply)
Hi,
I need to Change passwd for bulk servers using SSH script.
I have one server, from which i can reach all the servers without password via SSH.
There is some expect script, from which i can achieve it.
Can any one help me out here.
Thanks in advance.
Vicky (1 Reply)
I am having the 15 servers which need to do the monitoring
Hi I need a shell script, By which i can log in to multiple servers and execute the commands.. I need to specify the username and password in the scripts.
Please help me to write the script so that it can login with username and... (5 Replies)
I need run a command such as ps -ef |grep xxx on a batch of servers, how to write a script to run it without password? don't need go in each server to check?
Thanks (7 Replies)
Hi,
I have a requirement where in i need to write a shell script to set users password to never expire. I know the command which is used to perform the same .. which is chage command.
But, could not figure out how to do the same in shell script.
Could you please help me with the shell... (3 Replies)
Discussion started by: suren424
3 Replies
LEARN ABOUT DEBIAN
chpasswd
CHPASSWD(8) System Management Commands CHPASSWD(8)NAME
chpasswd - update passwords in batch mode
SYNOPSIS
chpasswd [options]
DESCRIPTION
The chpasswd command reads a list of user name and password pairs from standard input and uses this information to update a group of
existing users. Each line is of the format:
user_name:password
By default the passwords must be supplied in clear-text, and are encrypted by chpasswd. Also the password age will be updated, if present.
By default, passwords are encrypted by PAM, but (even if not recommended) you can select a different encryption method with the -e, -m, or
-c options.
Except when PAM is used to encrypt the passwords, chpasswd first updates all the passwords in memory, and then commits all the changes to
disk if no errors occured for any user.
When PAM is used to encrypt the passwords (and update the passwords in the system database) then if a password cannot be updated chpasswd
continues updating the passwords of the next users, and will return an error code on exit.
This command is intended to be used in a large system environment where many accounts are created at a single time.
OPTIONS
The options which apply to the chpasswd command are:
-c, --crypt-method METHOD
Use the specified method to encrypt the passwords.
The available methods are DES, MD5, NONE, and SHA256 or SHA512 if your libc support these methods.
By default, PAM is used to encrypt the passwords.
-e, --encrypted
Supplied passwords are in encrypted form.
-h, --help
Display help message and exit.
-m, --md5
Use MD5 encryption instead of DES when the supplied passwords are not encrypted.
-R, --root CHROOT_DIR
Apply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR directory.
-s, --sha-rounds ROUNDS
Use the specified number of rounds to encrypt the passwords.
The value 0 means that the system will choose the default number of rounds for the crypt method (5000).
A minimal value of 1000 and a maximal value of 999,999,999 will be enforced.
You can only use this option with the SHA256 or SHA512 crypt method.
By default, the number of rounds is defined by the SHA_CRYPT_MIN_ROUNDS and SHA_CRYPT_MAX_ROUNDS variables in /etc/login.defs.
CAVEATS
Remember to set permissions or umask to prevent readability of unencrypted files by other users.
CONFIGURATION
The following configuration variables in /etc/login.defs change the behavior of this tool:
SHA_CRYPT_MIN_ROUNDS (number), SHA_CRYPT_MAX_ROUNDS (number)
When ENCRYPT_METHOD is set to SHA256 or SHA512, this defines the number of SHA rounds used by the encryption algorithm by default (when
the number of rounds is not specified on the command line).
With a lot of rounds, it is more difficult to brute forcing the password. But note also that more CPU resources will be needed to
authenticate users.
If not specified, the libc will choose the default number of rounds (5000).
The values must be inside the 1000-999,999,999 range.
If only one of the SHA_CRYPT_MIN_ROUNDS or SHA_CRYPT_MAX_ROUNDS values is set, then this value will be used.
If SHA_CRYPT_MIN_ROUNDS > SHA_CRYPT_MAX_ROUNDS, the highest value will be used.
Note: This only affect the generation of group passwords. The generation of user passwords is done by PAM and subject to the PAM
configuration. It is recommended to set this variable consistently with the PAM configuration.
FILES
/etc/passwd
User account information.
/etc/shadow
Secure user account information.
/etc/login.defs
Shadow password suite configuration.
/etc/pam.d/chpasswd
PAM configuration for chpasswd.
SEE ALSO passwd(1), newusers(8), login.defs(5), useradd(8).
shadow-utils 4.1.5.1 05/25/2012 CHPASSWD(8)