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How to Use Special Keys in UNIX

UNIX operating system has some special keys. These you can use to interrupt the program processing or to resume it. The file management and keys totally different in UNIX kinds of operating systems. 



An example of a UNIX special key and its use.
Why You Need Interruption
A scenario where you made some mistake in the input command and you need to stop the further process. Then you can use the CTRL+C command. It is equal to the DELETE command.

List of UNIX Special Keys


RETURN key — The RETURN key signifies the end of a line of input. On any terminal, RETURN has a key of its own, or return may be typed by holding down the control key and typing a 'm'.Ctrl-m
Hint: Ctrl-m command is equal to RETURN key in Unix systems


DELETE: The DELETE key stops a program/command immediately, without waiting for it to finish. DELETE can be achieved equivalently with ctrl-c.
Hint: Ctrl-c Command you can use to interrupt the process.


Ctrl-s: Ctrl-s pauses the output and the program is suspended until you sta…

Storage area network (SAN): Networks Vs Configurations

These are most popular terms used in Storage area networks area. Every developer must know these terms clearly. Highly useful to explain in interviews. Frequently used terminology in SAN given below for your quick reference. 


SAN Network

  • Fibre channel - Fibre channel denotes a fibre-optical connection to a device or component. This is typically abbreviated as FC.
  • Host bus adapter - A host bus adapter is used by a given machine to access a storage area network. A host bus adapter is similar in function to a network adapter and how it provides access for a machine to a local area network or wide area network. This is typically abbreviated as HBA.
  • Storage area network - A storage area network is a network of shared devices that can typically be accessed using fibre. Often, a storage area network is used to share devices between many different machines. This is typically abbreviated as SAN


SAN Configurations

  • Point to point - This is the simplest configuration. The devices are connected directly to the HBA.
  • Arbitrated loop - Arbitrated loop topologies are ring topologies and are limited in terms of the number of devices that are supported on the loop and the number of devices that can be in use at a given time. In an arbitrated loop, only two devices can communicate at the same time. Data being read from a device or written to a device is passed from one device on the loop to another until it reaches the target device. The main limiting factor in an arbitrated loop is that only two devices can be in use at a given time.
  • Switched fabric - In a switched fabric SAN, all devices in the fabric will be fibre native devices. This topology has the greatest bandwidth and flexibility because all devices are available to all HBAs through some fibre path.

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