I have a user user1 which is part of wheel group and has all the root privileges .
user1 is able to change password for user2 using the below command (My understanding is that here passwd is run as root):
[user1@rhel-85 ~]$ sudo passwd user2 However, when user1 tries to run passwd as user2, I am getting an error:
[user1@rhel-85 ~]$ su -u user2 passwd Try 'su --help' for more information. [user1@rhel-85 ~]$ su is used to launch a root shell that allows all further commands to use root access. su has no -u option...
https://man7.org/linux/man-pages/man1/su.1.html
This is why it is saying/complains;
Try 'su --help' for more information.
You would need to add user1 to the wheel group, then as Bodo points out, execute;
sudo -u user2 passwd It's clear to me that sudo is your intended use here, as you are trying to execute a single command with temporary privilege elevation. (which is what sudo is for).
However, for completeness and as user Bib points out, you could execute;
su - _user_ foo ...which would allow you to run as root for another user.
This is the 'login shell' option for su (-, -l or --login). This is also handy for granting root privileges in the scenario, where the user doesn't have sudo privileges (and where the admin don't want them to, either.).
su - _user_ to run a command as another user. It's not limited to root.
sudoandsu. These two programs have different command line syntax and slightly different purpose. Do you meansudo -u user2 passwd?sudo -u user2 passwd. By the way, can you please help understand difference betweensudoandsu?