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View Full Version : sudo su -- vs. sudo su -


pushembekar
20th March 2006, 21:15
Hello everybody,

I was wondering if someone could tell me the difference between the commandssudo su -- and sudo su -

I noticed that when I use sudo su - I cannot open certain applications like gedit. That is what piqued my interest in this area.

Thanks.

dishawjp
25th March 2006, 16:50
Perhaps there are options to the sudo command that I'm not familiar with, but I think that it's possible that you've confused two somewhat similar commands.

The "sudo" command allows users specified in a sudoers file which is usually located in the /etc directory to perform certain functions (again, as permitted by the sudoers file) that are normally reserved for the root user. The syntax would be something like:

sudo <command>

where <command> is normally limited to the root user. You may be prompted for your normal user password, and if the root user has given you permission (in the sudoers file) to perform that action, you can.

The "su" command is a "switch user" command. In its simplest form, typing "su" will prompt you for the root password and if given correctly you get root privileges. Typing "su -" and giving the correct password gives you root's privileges and environment. The "su" command can also be used to gain access to another "normal" user's account if you have that user's password. To do that you would type "su <username>" where <username> is a valid normal user on that system.

This is my understanding of these commands. If those you listed are valid commands, I apologize for any misleading information, but the ones I described are definitely valid Linux commands.

HTH,

Jim

<edit>
gedit should take no special privileges to open. You may need root privileges to edit certain files though.
</edit>

Jim

sbovisjb1
25th March 2006, 17:00
Well in Ubuntu (im assuming you are using it) sudo su - gives you super user privlages for that account to make changes to and such. sudo su -- gives you privialdges for the ENTIRE server... thats why some apps dont work for su - because the changes (like boot or some apps) will affect all users. Now that difference won't affect you if you're the admin or dont have any other users apart from you're self but you can actually edit permssions (such as boot or yum/apt-get privaladges with a few scripts.....