Linux Interview Questions and Answers – Part 1
1.What is Unix?
Unix is a powerful, multi-user environment that has been implemented on a variety of platforms. Once the domain of servers and advanced users, it has become accessible to novices as well through the popularity of Linux and Mac OS X. With the notable exception of Microsoft Windows, all current major operating systems have some kind of Unix at their cores.
Unix was developed at Bell Labs in 1969, but in the past three decades many others have contributed to its evolution. In reality, Unix is not so much a single operating system as it is a standard upon which organizations and companies base their own systems. Examples of Unix implementations include Mac OS X/Darwin (Apple), GNU/Linux, AIX (IBM), Solaris (Sun), IRIX (SGI), and FreeBSD. They have different graphical interfaces, but from the Unix shell, a command line feature common to all versions, they are very similar.
Most of the UITS shared central systems at Indiana University are Unix servers and workstations, including Big Red (research; no email) and Quarry (general use, research; no email).
As with other operating systems, there are many kinds of applications available on a Unix system. Email, newsreading, programming, statistics, and graphics are some of the areas for which Unix software exists. Unix was once distinct from other operating systems because of its high level of integration with the network and its multi-user environment. Each user who logs in can have an environment distinct from that of any other user. In recent years, however, this distinction has blurred as other operating systems have developed these capacities. With the introduction of Mac OS X and the increasing popularity of free Unix systems like Linux and FreeBSD, as well as advanced interfaces based on the X Window System, more individuals are also using Unix as the operating system for their personal workstations.
2.What is linux?
Linux (often pronounced LIH-nuhks with a short “i”) is a Unix-like operating system that was designed to provide personal computer users a free or very low-cost operating system comparable to traditional and usually more expensive Unix systems. Linux has a reputation as a very efficient and fast-performing system. Linux’s kernel (the central part of the operating system) was developed by Linus Torvalds at the University of Helsinki in Finland. To complete the operating system, Torvalds and other team members made use of system components developed by members of the Free Software Foundation for the GNU Project.
Linux is a remarkably complete operating system, including a graphical user interface, an X Window System, TCP/IP, the Emacs editor, and other components usually found in a comprehensive Unix system. Although copyrights are held by various creators of Linux’s components, Linux is distributed using the Free Software Foundation’s copyleft stipulations that mean any modified version that is redistributed must in turn be freely available.
Unlike Windows and other proprietary systems, Linux is publicly open and extendible by contributors. Because it conforms to the Portable Operating System Interface standard user and programming interfaces, developers can write programs that can be ported to other operating systems. Linux comes in versions for all the major microprocessor platforms including the Intel, PowerPC, Sparc, and Alpha platforms. It’s also available on IBM’s S/390. Linux is distributed commercially by a number of companies. A magazine, Linux Journal, is published as well as a number of books and pocket references.
Linux is sometimes suggested as a possible publicly-developed alternative to the desktop predominance of Microsoft Windows. Although Linux is popular among users already familiar with Unix, it remains far behind Windows in numbers of users. However, its use in the business enterprise is growing.
3.What is server?
i) A computer or device on a network that manages network resources. There are many different types of servers. For example:
- File server: a computer and storage device dedicated to storing files. Any user on the network can store files on the server.
- Print server: a computer that manages one or more printers, and a network server is a computer that manages network traffic.
- Database server: a computer system that processes database queries.
Servers are often dedicated, meaning that they perform no other tasks besides their server tasks. On multiprocessing operating systems, however, a single computer can execute several programs at once. A server in this case could refer to the program that is managing resources rather than the entire computer.
ii) A computer, or a software package, that provides a specific kind of service to client software running on other computers. The term can refer to a particular piece of software, such as a WWW server, or to the machine on which the software is running, e.g. “Our mail server is down today, that’s why e-mail isn’t getting out.” A single server machine can (and often does) have several different server software packages running on it, thus providing many different servers to clients on the network. Sometimes server software is designed so that additional capabilities can be added to the main program by adding small programs known as servlets
4.what are the flover’s are the in Linux?
5.What is computer networking?
A computer network is a system in which computers are connected to share information and resources. The connection can be done as peer-to-peer or client/server. This web site reviews the techniques you can use to set up and possibly manage a network for home or a small business.
6.What is Ethernet card?
The system that helps connect a computer to an Ethernet network is called an Ethernet card. Another name for such a card is Network Interface Card (NIC). It can be inserted into one of the slots provided on the motherboard of the computer. Each of these cards has a unique identification number, known as the MAC address.
Ever since their inception by the Xerox Company, Ethernet cards have managed to find their way into nearly every single computer in the world.
The Ethernet card was created to build a Local Area Network (LAN). Once Ethernet cable is connected to the Ethernet cards of two or more computers over the LAN, one can transfer files and data. This can be carried out for external hardware such as printers and scanners when information from one computer needs to be transferred to another computer.
Since technology has advanced greatly, there are wireless Ethernet cards also available, which make use of radio waves for data transmission. In case such connections are used, there will be a small antenna for transmitting data and carrying out requests from one machine to the other. These are prone to security breaches and so information security systems need to be kept up to date in computers that use them.
These days most of the computers come with built in Ethernet cards, and unless specified one need not install them. Driver software is required for the card to work, which should be installed before the card can be used. An Ethernet card is hundreds of times faster than a modem and is ideal in an environment where two or more computers need to be interlinked
7.What Is a MAC Address?
The MAC address is a unique value associated with a network adapter. MAC addresses are also known as hardware addresses or physical addresses. They uniquely identify an adapter on a LAN.
MAC addresses are 12-digit hexadecimal numbers (48 bits in length). By convention, MAC addresses are usually written in one of the following two formats:
The first half of a MAC address contains the ID number of the adapter manufacturer. These IDs are regulated by an Internet standards body (see sidebar). The second half of a MAC address represents the serial number assigned to the adapter by the manufacturer. In the example,
indicates the manufacturer is Intel Corporation.
8.1024 GB = 1,048,576 KB
9.17408 bytes ==?kb
17 kilobytes = 17408 bytes
10.What is LAN?
A local area network (LAN) supplies networking capability to a group of computers in close proximity to each other such as in an office building, a school, or a home. A LAN is useful for sharing resources like files, printers, games or other applications. A LAN in turn often connects to other LANs, and to the Internet or other WAN.
Most local area networks are built with relatively inexpensive hardware such as Ethernet cables, network adapters, and hubs. Wireless LAN and other more advanced LAN hardware options also exist.
Specialized operating system software may be used to configure a local area network. For example, most flavors of Microsoft Windows provide a software package called Internet Connection Sharing (ICS) that supports controlled access to LAN resources.
The term LAN party refers to a multiplayer gaming event where participants bring their own computers and build a temporary LAN.
Also Known As: local area network
The most common type of local area network is an Ethernet LAN. The smallest home LAN can have exactly two computers; a large LAN can accommodate many thousands of computers. Many LANs are divided into logical groups called subnets. An Internet Protocol (IP) “Class A” LAN can in theory accommodate more than 16 million devices organized into subnets.
Types of Local-Area Networks (LANs)
There are many different types of LANs, with Ethernets being the most common for PCs. Most Apple Macintosh networks are based on Apple’s AppleTalk network system, which is built into Macintosh computers.
The following characteristics differentiate one LAN from another:
topology : The geometric arrangement of devices on the network. For example, devices can be arranged in a ring or in a straight line.
protocols : The rules and encoding specifications for sending data. The protocols also determine whether the network uses a peer-to-peer or client/server architecture.
media : Devices can be connected by twisted-pair wire, coaxial cables, or fiber optic cables. Some networks do without connecting media altogether, communicating instead via radio waves.