umask is a Unix shell built-in command that automatically sets file permissions on newly created files. The umask command can be confusing to use because it does work as a mask. In other words, the user sets the permissions that he/she does not want in the umask. To calculate permissions that will result from specific …
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, …
Keeping track of your CPU’s performance is extremely important. In UNIX, you can accomplish this task by using the system utilities and commands. For those who would like to find out their CPU utilization, one command is extremely important. It is called SAR – System Activity Reporter. The SAR commands make accessing CPU performance quite …
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 …
List Logged In Unix Users Unix has many commands to list users who are logged in. These commands include ‘w,’ ‘who,’ and ‘users:’ $ w 9:51PM up 99 days, 5:39, 2 users, load averages: 0.83, 0.90, 0.90 USER TTY FROM LOGIN@ IDLE WHAT will p0 c-66-164-235-73. 8:11AM – w spencer p3 c-66-164-235-73. 8:26PM 1:24 pine …
Bootable distributions of the Linux operating system are becoming very popular for use in securing networks, testing network security, and conducting forensics after suspected intrusions. Local Area Security Linux Local Area Security Linux is a ‘Live CD’ distribution with a small footprint. Containing over 200 information security and administration related tools, as well as a …
Unix file permissions are based upon an octal code. Unix file permissions are stored in a ten character array. The first character of the file permissions stores the file type. The standard file types are: Character Meaning – Plain file d Directory c Character device b Block device l Symbolic link s Socket = or …
Linux is a free, open source operating system that competes with the Windows Operating Systems and Mac OS X. Linux is widely used on a number of devices such as servers, desktops, laptops, smartphones, PDAs, game consoles, tablet computers, supercomputers, and mainframes. Linux controls only about 4.9% of the market share of desktop computers while …
DHCP is the dynamic host configuration protocol. In other words, it describes how your computer is connected to networks. Assigning an IP address dynamically is a basic task assigned to DHCP along with domain name, name server, gateway, host name and net mask. DHCP can provide other information like time server and has a capability …
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 …