A restricted shell is a Unix shell that has been modified to allow the Unix shell user to do fewer things than a normal shell would allow him to do. It may allow the user to run only certain programs. It may stop the user from changing directories. Many sites run their own restricted shells …
To change an IP address on a Solaris system immediately, use the `ifconfig` command. The syntax for `ifconfig` is: ifconfig <interface> <ip address> <netmask> <broadcast address> If the user does not know his/her network interface names, he/she should use the `ifconfig -a` command to list all of the available network interfaces. Permanently Change an IP …
Free derivatives of Unix can be easily downloaded via the Internet. This sets Unix apart from other proprietary operating systems like Microsoft Windows. The different Unix versions and Unix-like operating systems available for download include FreeBSD, OpenBSD, Red Hat Fedora Linux, Debian Linux, Ubuntu Linux, and Sun Solaris. Those who are new to Unix or …
The total number of Unix commands is immense. No normal user or system administrator would ever need to know them all. The Unix commands available to you will vary based upon several factors: The version of Unix you are using (FreeBSD, Linux, Solaris, AIX, HP-UX, OpenBSD, etc…) The Unix shell you are using (sh, csh, …
A computer process is a computer program that is executing and has a unique process identification or PID. On the Unix Operating System (OS), a process may be running in the background, foreground, or be in a suspended state. On Unix, the OS shell will not return the prompt to the end-user until the current …
To audit Unix passwords, you must compare each encrypted password in the Unix password file with a set of potential encrypted passwords. These potential encrypted passwords are created by encrypting every password in a list of plaintext passwords. This is an example of a dictionary attack. The Unix passwd File Location The traditional location for …
The Unix find command, as the name implies, is a command that you can enter into the command line, or terminal, of a Unix operating system, allowing you to process any given set of files or directories. It is a highly useful command that you can take advantage of on Unix based operating system, making …
Solaris makes it unreasonably difficult to change an installed server’s hostname. To change the hostname on a Solaris system, edit all of these files: /etc/hosts /etc/nodename /etc/hostname.* /etc/inet/ipnodes When file editing is complete, reboot the server to test the changes and ensure that they operate correctly. Note that changing the hostname only changes the name …
Unix users write, edit, list, and remove cron jobs using the `crontab` command. `crontab -e` takes users into their default editor to edit their crontab entries. `crontab -l` lists their crontab. `crontab -r` removes their crontab. crontab Security If the cron.allow file exists, then the user must be listed in that file in order to …
UNIX is one of the most important operating systems ever developed. What made Unix stand out in the crowd of countless other operating systems is that it was a competent operating system that was extremely affordable and worked on low cost hardware. Economics definitely played a large part in UNIX’s popularity and today it is …