09-17-2010
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
I recently went in for a job interview and the guy asked me what I knew about Unix. I told him not much since I haven't worked with it in a few years. He then asked me the following question: What Unix or Linux shell command will tell you the names of all files in the current directory, along... (2 Replies)
Discussion started by: BMWBigD
2 Replies
2. Solaris
solaris 10
logged in as root to command line...want to shut the system down....could not do this....when i chose shutdown the system seemed to squawk at me saying i'd lose whatever i was working on would be lost unless i logged out...after proceeding through this it took me to the gui log in... (6 Replies)
Discussion started by: drisnya
6 Replies
3. Shell Programming and Scripting
Hi ,
I have a piece of code ...wherein I need to assign the following ...
1) A command line argument to a variable
e.g origCount=ARGV
2) A unix command to a variable
e.g result=`wc -l testFile.txt`
in my awk shell script
When I do this :
print "origCount" origCount --> I get the... (0 Replies)
Discussion started by: sweta_doshi
0 Replies
4. UNIX for Advanced & Expert Users
Hi,
Well my title isn't very clear I think. So to understand my goal:
I have a script "test1"
#!/bin/bash
xvkbd -text blabla
with xbindkeys, I bind F5 key in order it runs my test1 script
So when I press F5, test1 runs.
I'm under Emacs/Vi and I press F5 in order to have "blabla" be... (0 Replies)
Discussion started by: xib.be
0 Replies
5. UNIX for Dummies Questions & Answers
I am going through the Unix Made Easy second edition book by John Muster. So far it's been very informative and I can tell it may be a bit out of date.
In one of the exercises it talks about the "sort" command and using it to sort column's of data etc. The "sort" command has changed a bit and... (1 Reply)
Discussion started by: budfoxcat
1 Replies
6. Shell Programming and Scripting
I'm trying to write a bash script called YN that looks like the following
YN "Specify a question" "doThis" "doThat"
where "doThis" will be executed if the answer is "y", otherwise "doThat".
For example
YN "Do you want to list the file dog?" "ls -al dog" ""
Here's my attempt... (3 Replies)
Discussion started by: LeoKSimon
3 Replies
7. UNIX for Dummies Questions & Answers
Hi Guys,
I am new on the scripting world and would like ask for help if you can.
Here are my questions below:-
What Unix command(s) would you put in a shell script to read an ASCII comma-delimited input file and validate that field 5 only contains numeric characters?
What Unix command(s)... (5 Replies)
Discussion started by: mahiwaga
5 Replies
8. UNIX for Beginners Questions & Answers
:D:D:D
These are list of command i typed on opensuse terminal and evolve lots of doubt around ,that i can't answer.
COMMAND 1 linux-xavv:/ # cd
COMMAND 2 linux-xavv:~ #
Does above command 1 and command two with red labelled sign make different meaning or same .
1
linux-xavv:/... (1 Reply)
Discussion started by: lobsang
1 Replies
9. UNIX for Beginners Questions & Answers
OS : RHEL / Oracle Linux 6.8
In bash shell, how can I replace a character under the cursor with another character ?
In the below example , after I typed the following line, I realized that I meant 7013 and not 2013. So I move the cursor to the left and keep it on top of 2 (of 2013) and I want... (7 Replies)
Discussion started by: kraljic
7 Replies
10. UNIX for Beginners Questions & Answers
Hey guys, so I want to start using the terminal when I do thinks like update, commit and whatnot. I am use to using kdesvn which is a GUI that helps me with subversion. However, kdesvn does not seem to play well on 18.04 and regardless I am trying to move away from GUI's in general. I want to... (1 Reply)
Discussion started by: Circuits
1 Replies
LEARN ABOUT LINUX
sudo_root
sudo_root(8) System Manager's Manual sudo_root(8)
NAME
sudo_root - How to run administrative commands
SYNOPSIS
sudo command
sudo -i
INTRODUCTION
By default, the password for the user "root" (the system administrator) is locked. This means you cannot login as root or use su. Instead,
the installer will set up sudo to allow the user that is created during install to run all administrative commands.
This means that in the terminal you can use sudo for commands that require root privileges. All programs in the menu will use a graphical
sudo to prompt for a password. When sudo asks for a password, it needs your password, this means that a root password is not needed.
To run a command which requires root privileges in a terminal, simply prepend sudo in front of it. To get an interactive root shell, use
sudo -i.
ALLOWING OTHER USERS TO RUN SUDO
By default, only the user who installed the system is permitted to run sudo. To add more administrators, i. e. users who can run sudo, you
have to add these users to the group 'admin' by doing one of the following steps:
* In a shell, do
sudo adduser username admin
* Use the graphical "Users & Groups" program in the "System settings" menu to add the new user to the admin group.
BENEFITS OF USING SUDO
The benefits of leaving root disabled by default include the following:
* Users do not have to remember an extra password, which they are likely to forget.
* The installer is able to ask fewer questions.
* It avoids the "I can do anything" interactive login by default - you will be prompted for a password before major changes can happen,
which should make you think about the consequences of what you are doing.
* Sudo adds a log entry of the command(s) run (in /var/log/auth.log).
* Every attacker trying to brute-force their way into your box will know it has an account named root and will try that first. What they do
not know is what the usernames of your other users are.
* Allows easy transfer for admin rights, in a short term or long term period, by adding and removing users from the admin group, while not
compromising the root account.
* sudo can be set up with a much more fine-grained security policy.
* On systems with more than one administrator using sudo avoids sharing a password amongst them.
DOWNSIDES OF USING SUDO
Although for desktops the benefits of using sudo are great, there are possible issues which need to be noted:
* Redirecting the output of commands run with sudo can be confusing at first. For instance consider
sudo ls > /root/somefile
will not work since it is the shell that tries to write to that file. You can use
ls | sudo tee /root/somefile
to get the behaviour you want.
* In a lot of office environments the ONLY local user on a system is root. All other users are imported using NSS techniques such as
nss-ldap. To setup a workstation, or fix it, in the case of a network failure where nss-ldap is broken, root is required. This tends to
leave the system unusable. An extra local user, or an enabled root password is needed here.
GOING BACK TO A TRADITIONAL ROOT ACCOUNT
This is not recommended!
To enable the root account (i.e. set a password) use:
sudo passwd root
Afterwards, edit the sudo configuration with sudo visudo and comment out the line
%admin ALL=(ALL) ALL
to disable sudo access to members of the admin group.
SEE ALSO
sudo(8), https://wiki.ubuntu.com/RootSudo
February 8, 2006 sudo_root(8)