Section – a 2 Marks Questions
Q9. What do you mean by BOOTP and DHCP?
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Q9. What do you mean by BOOTP and DHCP? Ans. The DHCP method uses a DHCP server system to obtain its networking configuration. The BOOTP method is similar, requiring a BOOTP server to supply the networking configuration. The static method requires that you enter all the required networking information in the kickstart file. As the name implies, this information is static, and will be used during the installation, and after the installation as well. To direct a system to use DHCP to obtain its networking configuration, use the following line: network --bootproto dhcp BOOTP: - To direct a machine to use BOOTP to obtain its networking configuration, use the following line in the kickstart file: network --bootproto bootp The line for static networking is more complex, as you must include all network configuration information on one line. You’ll need to specify: • IP address • netmask • gateway IP address • name server IP address
These recommendations are based on an installation that only installs one language (such as English). If we plan to install multiple languages to use on your system, you should increase the disk space requirements. Q11. Explain the types of file system available in Linux? Ans. Red Hat Linux allows you to create different partition types, based on the file system they will use. The following is a brief description of the different file systems available, and how they can be utilized. ext2 :- An ext2 file system supports standard Unix file types (regular_les, directories, symbolic links, etc). It provides the ability to assign long file names, up to 255 characters. Versions prior to Red Hat Linux 7.2 used ext2 file systems by default. ext3 :- The ext3 _le system is based on the ext2 file system and has one main advantage of journaling. Using a journaling file system reduces time spent recovering a file system after a crash as there is no need to fsck1 the file system. The ext3 file system will select by default and is highly recommended. software RAID:- Creating two or more software RAID partitions allows you to create a RAID device. Swap :- Swap partitions are used to support virtual memory. In other words, data is written to a swap partition when there is not enough RAM to store the data your system is processing. Vfat : - The VFAT file system is a Linux file system that is compatible with Windows 95/NT long filenames on the FAT file system.
1. GRUB Provides a true command-based, pre-OS environment on x86 machines. This affords the user maximum flexibility in loading operating systems with certain options or gathering information about the system. For years many non-x86 architectures have employed pre-OS environments that allow system booting from a command line. While some command features are available with LILO and other x86 boot loaders, GRUB is more feature rich. 2. GRUB supports Logical Block Addressing (LBA) mode. LBA places the addressing conversion used to find files in the hard driver's firmware, and it is used on many IDE and all SCSI hard devices. Before LBA, boot loaders could encounter the 1024-cylinder BIOS limitation, where the BIOS could not find a file after that cylinder head of the disk. LBA support allows GRUB to boot operating systems from partitions beyond the 1024-cylinder limit, so long as the system BIOS supports LBA mode. Most modern BIOS revisions support LBA mode. 3. GRUB can read ext2 partitions. This allows GRUB to access its configuration file, /boot/grub/grub. conf, every time the system boots, Making clear the need for the user to write a new version of the first stage boot loader to MBR when configuration changes are made. The only time a user would need to reinstall GRUB on the MBR is if the physical location of the /boot partition is moved on the disk. Q13. Write down a short note on LILO v/s GRUB. Ans. In general, LILO works similarly to GRUB except for three major differences: 1. It has no interactive command interface. 2. It stores information about the location of the kernel or other operating system it is to load on the MBR. 3. It cannot read ext2 partitions. The first point means the command prompt for LILO is not interactive and only allows one command with arguments. The last two points mean that if you change LILO's configuration file or install a new kernel, you must rewrite the Stage 1 LILO boot loader to the MBR by issuing the /sbin/lilo - v -v command. This is more risky than GRUB's method, because a misconfigured MBR leaves the system unbootable. With GRUB, if the configuration file is erroneously configured, it will simply default to its command line interface. Q14. Write down a short note on Linux Windows Managers? Ans. Window managers are X client programs that control the way other X clients are positioned, resized, or moved. Window managers can also provide titlebars to windows, keyboard focus by keyboard or mouse, and user-specified key and mouse button bindings. Window managers work with a collection of different X clients, wrapping around the program, making it look a certain way and appear on the screen in a particular place. Four window managers are included with Red Hat Linux 8.0: 1. twm: - The minimalist Tab Window Manager, which provides the most basic toolset of any of the window managers. 2. mwm: -The default window manager for the GNOME desktop environment, mwm stands for Metacity Window Manager. It is a simple and efficient window manager which supports custom themes.
Red Hat Linux 8.0. It can be used either with or without the GNOME desktop environment. 4. wmaker: - WindowMaker is a full-featured GNU window manager designed to emulate the look and feel of the NEXTSTEP environment. These window managers can be run as individual X clients to gain a better sense of their differences. Type the xinit
When used correctly, PAM provides the following advantages for a system administrator: 1. It provides a common authentication scheme that can be used with a wide variety of applications. 2. It allows great flexibility and control over authentication for both the system administrator and application developer. 3. It allows application developers to develop their program without implementing a particular authentication scheme.
SSH (or Secure SHELL) is a protocol for creating a secure connection between two systems using a client server architecture. Under the SSH protocol, the client machine initiates all connections to a server. The SSH protocol provides the following safeguards: 1. After an initial connection, the client verifies it is connecting to the same server during subsequent sessions. 2. The client transmits its authentication information to the server, such as a username and password, in an encrypted format. 3. All data sent and received during the connection is transferred using strong, 128 bit encryption, making intercepted transmissions extremely difficult to decrypt and read. 4. The client has the ability to use X11 1 applications launched from the shell prompt. This technique, called X11 forwarding, provides a secure means to use graphical applications over a network. 5. Because the SSH protocol encrypts everything it sends and receives, it can be used to secure otherwise insecure protocols. Using a technique called port forwarding, an SSH server can become a conduit to secure insecure protocols, like POP, increasing overall system and data security. A large number of client and server programs can use the SSH protocol. Several different SSH client versions are available for almost every major operating system in use today. Even if the users connecting to your system are not running Red Hat Linux, they can still find and use an SSH client native for their operating system. Q17. Define GNOME Basic in detail? Ans. Gnome is quite similar to the windows, but there are two significant differences: the first is that there is no My Computer icon on the desktop. This is because Linux does not have the concept of separate drive letters for each partition. Rather, all of the partitions are made available in a single directory tree, thereby eliminating the need to select a drive. The second big difference is the panel at the bottom of the screen. This panel is similar to the Windows XP taskbar; it shows what applications are currently running, as well as the date and time, and the red hat button at the left side of the panel is similar to the Start button. The big difference is that this panel is completely configurable: You can move things around in it, dock dynamic applications, set up shortcuts to other applications, and move around your virtual desktops. By default, the buttons available on the panel are, from left to right, the Start Menu, web browser (Mozilla), e-mail manager (Evolution), word processor (OpenOffice.org Writer), presentation tool (OpenOffice.org Impress), spreadsheet (OpenOffice.org Calc), and a workspace switcher for moving between virtual desktops. On the left-hand side of the panel are Red Hat’s “critical updates notifier” and a clock. Q18. What do you mean by DNS? Ans. Systems using IP networks must know the IP address of a remote machine in order to connect to it. However, most users prefer to use the name of a machine, called a hostname or a fully qualified domain name (FQDN), when connecting to it. Fully qualified domain names also have advantages for system administrators. They allow administrators to flexibility in changing the IP addresses for individual machines without effecting name-based queries to the machines. Conversely, administrators can shuffle which machines handle a name-based query in a way transparent to the user. The service that facilitates this is caused DNS, and it is normally implemented using centralized servers that are authoritative for some domains and refer to other DNS servers for other domains. DNS under Linux is made possible through the use of a nameserver daemon that performs the IP/hostname translation. A client application will request information from the nameserver, usually connecting to it on the server's port 53. The nameserver will attempt to resolve the FQDN based on its resolver library, which may contain authoritative information about the host requested or cached data about that name from an earlier query. If the nameserver does not already have the answer in its resolver library, it will turn to\ other nameserver, called root nameserver, to determine which nameserver are authoritative for the FQDN in question. Then, with that information, it will query the authoritative nameserver for that name to determine the IP address. If performing a reverse lookup, the same procedure is used, except the query is made with an unknown IP address rather than a name.
Once the NFS file system is mounted read-write by a remote host, protection for each shared file involves its permissions, and its user and group ID ownership. If two users that share the same user ID value mount the same NFS file system, they will be able to modify each others files. Additionally, anyone logged in as root on the client system can use the su - command to become a user who could access particular files via the NFS share. The default behavior when exporting a file system via NFS is to use root squashing. This sets the user ID of anyone accessing the NFS share as the root user on their local machine to a value of the server's nobody account. You should never turn off root squashing unless multiple users with root access to your server does not bother you. If you are only allowing users to read files via your NFS share, consider using the all squash option, which makes every user accessing your exported file system to take the user ID of the nobody user. Q20. What do you mean by LDAP? Ans. Lightweight Directory Access Protocol (LDAP) is a set of open protocols used to access centrally stored information over a network. It is based on the X.500 standard for directory sharing, but is less complex and resource intensive. For this reason, LDAP is sometimes referred to as X.500 Lite. Like X.500, LDAP organizes information in a hierarchal manner using directories. These directories can store a variety of information and can even be used in a manner similar to Network Information Service (NIS), enabling anyone to access their account from any machine on the LDAP enabled network. In most cases, however, LDAP is used simply as a virtual phone directory, allowing users to easily access contact information for other users. But LDAP goes beyond a traditional phone directory, because it is capable of propagating its directories to other LDAP servers throughout the world, providing global access to information. Currently, however, LDAP is more commonly used within individual organizations, like universities, government departments, and private companies. LDAP is a client-server system. The server can use a variety of databases to store a directory, each optimized for quick and copious read operations. When an LDAP client application connects to an LDAP server it can either query a directory or upload information to it. In the event of a query, the server either answers the query or, if it can not answer locally, it can refer the query upstream to a higher level LDAP server which does have the answer. If the client application is attempting to upload information to an LDAP directory, the server verifies that the user has permission to make the change and then adds or updates the information. Uses for LDAP Several Netscape applications, including Netscape Roaming Access are LDAP-enabled. Send mail can use LDAP to look up addresses. Any organization can use LDAP as an organization-wide directory and/or name service. We can even use a personal LDAP server to keep track of personal e-mail address book. LDAP can be used as an authentication service via the pam_ldap module. LDAP is commonly used as a central authentication server so that users have a unified login that covers console logins, POP servers, IMAP servers, machines connected to the network using Samba, and even Windows NT machines. All of these login situations can rely on the same user ID and password combination, using LDAP. The pam_ldap module is provided in the nss_ldap package.
[root@ptu /root] # mount technics:/export/SL1200/MK2 /projects/secret Q2. Why does it take a long time to move a big directory to another file system, yet when I move a directory within a file system it takes only seconds? Ans. Since filename are stored in the directory I-node, a copy within the file system simply involves updating the directory I-node to print to the I-node containing the data. When you copy across file system, I-node don’t transfer, so you have to create all of the I-nodes of the original file or files. Q3. Describe the emacs? Ans. It has been argued that emacs is an operating system all by itself. It’s big, feature-Orich expandable, programmable and all-around amazing. Emacs is easy for user aware of GUI. Yet underneath is a complete interface to the GNU development environment, a mail reader, a newsreader, a web browser and even a psychiatrist. Q4. Describe the Pico. Ans. Pico is another editor inspired by simplicity. Typically used in conjunction with the pine mail reading system, Pico can also be used as standalone editor. Like joe, it can work in a manner similar to Notepad, but Pico uses its own set of key combinations. Q5. Describe the redirection. Ans. Through redirection we can take output of program and have it automatically sent to a file. The shell rather that the program itself handles this process, thereby providing a standards mechanism fog performing the task. [root@ptu /root]# Is > /tmp/directoryt_listing Q6. How do you set an environment variable? Ans. To set an environment variable, use the following format: #variable=value #FOO=BAR
The vertical bar ( | ) character represents the pipe between printenv and grep. Q8. What information is stored in the /etc/group file? Ans. Each user belongs to at least one group, that being their default group. Users number then be assigned to additional groups id need if needed. The /etc/passwd file contains contain each user’s default GID. This GID is mapped to the group’s named and other members of the group in the /etc/group file is Group name Encrypted password for the group GID number Comma-separated list of member users.
#rpm –1 –force –nodeps Q14. What command is used to query the RPM database? Directory: wp-content -> uploads -> 2016 2016 -> 2017 afoCo Landmark Scholarship Program 2016 -> Instructions for the Preparation of Camera-Ready Contributions to the Conference Proceedings 2016 -> Step student Scholarships for Year 10-13 2016 -> The united church of canada 2016 -> Idan raichel biography – May 2016 Brief Producer, keyboardist, Lyricist, composer and Performer Idan Raichel 2016 -> An introduction to centre’s interventions expanding access to justice 2016 -> Sanchar Shakti 2016 -> Unit analysis should help here. We want number of bananas 2016 -> The Autobiography of Elder Joseph Bates 2016 -> The Great Heat and the Rhode Island Deep Water Bay Scallop (Argopecten irradians) Fishery 1875-1905 Download 495.38 Kb. Share with your friends:
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