Page 212 - DCAP602_NETWORK_OPERATING_SYSTEMS_I

Network Operating Systems-I

notes five-minute period without being re-prompted for a password. All commands run as sudo are
logged in the log file /var/log/messages.

Did u know? How can we run the privileged command?

Example: Using sudo is relatively simple as we can see from these examples.

temporarily gaining root privileges
In this example, user bob attempts to view the contents of the /etc/sudoers file, which is an
action that normally requires privileged access. Without sudo, the command fails:

[bob@bigboy bob]$ more /etc/sudoers
/etc/sudoers: Permission denied
[bob@bigboy bob]$
Bob tries again using sudo and his regular user password and is successful:

[bob@bigboy bob]$ sudo more /etc/sudoers
Password:
...
...

[bob@bigboy bob]$
The details of configuring and installing sudo are covered in later sections.

Becoming root for a complete Login session

The su command allows a regular user to become the system’s root user if they know the root
password. A user with sudo rights to use the su command can become root, but they only need
to know their own password, not that of root as seen here.

someuser@u-bigboy:~$ sudo su -
Password:
root@u-bigboy:~#
Some systems administrators will use sudo to grant root privileges to their own personal user
account without the need to provide a password.
Later sections describe how to disable sudo su ability and also how to use sudo without password
prompts.

Downloading and installing the sudo package

Fortunately the package is installed by default by RedHat/Fedora which eliminates the need to
anything more in this regard.

the visudo command

The visudo command is a text editor that mimics the vi editor that is used to edit the /etc/
sudoers configuration file. visudo uses the same commands as the vi text editor. The visudo
command must run as user root and should have no arguments:

[root@aqua tmp]# visudo

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