Wed 21-November-2012
Linux Commands: Know these commands and what they do:
• Directory and list commands o ls, ls –l o pwd o cd / o cd and cd~ (hint: both take you to your home directory) o cd .. (takes you up one directory
• Know what cp and mv do and how to use them
• File viewing commands: o cat o less and more (one page at atime) o vi and view o tail (shows the last 10 lines of a file) o head (shows the top 10 lines)
• chmod for changing permissions on files and directories
• know the differences in read write and execute for owner group and all
• > to redirect output to a file (overwrites if file exists)
• >> appends to a file
• & puts a process in the background while fg brings it to the foreground.
• ps –ef | grep programname locates a running process for you
• grep is a program that searches for a string within a directory or command output
• The pipe symbol ( | ) sends output from one command to the input of another.
• Know what a Linux shell script is.
Direcories and file systems
• / is the root of the entire file system
• /usr stores program files
• /home stores user home directories
• /etc stores Linux configuration files
• /var stores various miscellaneous files
• /proc is a virtual directory that stores system performance metrics. It does not exist on disk and disappears when the system is turned off.
• /tmp stores temporary files that disappear on system shutdown or reboot
• The file /etc/fstab links physical disk partitions to the filesystem directories
• The mount command links a new disk location to a new directory.
• NFS (Network File System) allows you to share directories and files with other Linux systems.
• The configuration for NFS is stored in /etc/exports
Runlevels
• Know what each run level 0-6 does and how to change levels with the telinit command
• Understand the differences between text based and graphical interfaces
• Understand the difference between single