Useful Protocol Abbreviations

    Some Useful Protocol Abbreviations

Protocol is the special set of rules that end points in a telecommunication connection use when they communicate. Protocols specify interactions between the communicating entities.

ARP        Address Resolution Protocol

AFP        AppleTalk Filing Protocol

ALP        Appliance Link Protocol

BGP       Border Gateway Protocol

BIND      Berkeley Internet Name Domain

BCP        Binary Control Protocol

BOP       Bit-Oriented Protocol

BOOTP  Bootstrap Protocol

CGI         Common Gateway Interface

DDP       Datagram Delivery Protocol

DHCP    Dynamic Host Configuration Protocol

DIP         Dialup Internet Protocol

DNS       Domain Name Server protocol

DRP        Distribution and Replication Protocol

ESMTP  Extended Simple Mail Transfer Protocol

ECP Encryption Control Protocol

EGP        Exterior Gateway Protocol

FCP        Fibre Channel Protocol

FTP         File Transfer Protocol

GTP        GPRS Tunnelling Protocol

GREP     Global Regular Expression Print

HTTPS   Secure HypterText Transfer Protocol

HTTP     Hypertext Transfer Protocol

IMAP     Interim Mail Access Protocol

IP            Internet Protocol

IIP           Internet Imaging Protocol

ICA         Independent Computing Architecture

IPP         Internet Printing Protocol

IGP         Interior Gateway Protocol

ICMP     Internet Control Message Protocol

IPv6       revised version of IP

ISCSI      Internet Small Computer Systems Interface

IGRP      Interior Gateway Routing Protocol

IDP         Internet Datagram Protocol

LAP        Link Access Procedure

LFTP       Leech File Transfer Protocol

LDAP     Lightweight Directory Access Protocol

L2F         Layer 2 Forwarding protocol, permits the tunneling of the link layer of higher layer protocols

L2TP       Layer 2 Tunneling Protocol, used for integrating multiprotocol dialup services into existing ISP POP

LAT         Local Area Transport protocol, designed to handle multiplexed terminal traffic to/from timesharing hosts

MARS    Multicast Address Resolution Server

MDLP    Mobile Data Link Protocol

MOP      Maintenance Operation Protocol, utility services such as uploading and downloading system software, remote testing and problem diagnosis

NTP        Network Time Protocol, time synchronization system for computer clocks through the Internet network

NNTP    Network News Transfer Protocol

NCP       NetWare Core Protocol

NFS        Sun Network File System, file sharing application for the Sun protocol suite.

OTP        Open Trade Protocol

OSPF     Open Shortest Path First, linkstate routing protocol used for routing IP

PPTP      PointtoPoint Tunneling Protocol, allows PPP to be channeled through an IP network

PPP        PointtoPoint Protocol, designed for simple links which transport packets between two peers.

POP3     Post Office Protocol version 3, permits workstations to dynamically access a maildrop on a server host

Ping         Packet Internet Groper

PAP        Printer Access Protocol, manages the virtual connection to printers and other servers

RIP         Routing Information Protocol, maintains a database of network hosts and exchange information about the topology of the network

RLOGIN                Remote Login, allows UNIX users of one machine to connect to other UNIX systems across the Internet and interact as if their terminals are directly connected to the machines

RLP         Radio Link Protocol

RPM      Red Hat Package Manager

RP           Routing Protocol, distributes routing information among DECnet hosts.

SSP         Serial Storage Protocol

SGD       Secure Global Desktop

SPF         Shortest Path First

SRP        Extreme Standby Router Protocol

SSH        Secure Shell

SLIP        Serial Line Internet Protocol

SSL         Secure Sockets Layer

SMB       Server Message Block, Microsoft presentation layer protocol providing file and print sharing functions for LAN Manager, Banyan VINES and other networking operating systems.

SMTP    Simple Mail Transfer Protocol, mail service modeled on the FTP file transfer service

SNMP   Simple Network Management Protocol, developed by the Internet community to allow diverse network objects to participate in a global network management architecture.

TCP        Transmission Control Protocol, provides a reliable stream delivery and virtual connection service to applications through the use of sequenced acknowledgement with retransmission of packets when necessary

TFTP      Trivial File Transfer Protocol, supports file writing and reading

TELNET Terminal emulation protocol

UDP       User Datagram Protocol, provides a simple but unreliable message service for transaction oriented services

ULP        Upper Layer Protocol

UDA       Universal Data Access

VRRP     Virtual Router Redundancy Protocol

VPN       Virtual Private Network

VCI          Virtual Channel Identifier.

VSFTPD Very Secure File Transfer Protocol Daemon

WDP      Wireless Datagram Protocol

WSP      Wireless Session Protocol

WAP      Wireless Application Protocol

WDOG Watchdog protocol, provides constant validation of active workstation connections and notifies the NetWare operating system when a connection may be terminated as a result of lengthy periods without communication

WTP      Wireless Transaction Protocol

XMPP    Extensible Messaging and Presence Protocol

YUM      Yellowdog Updater Modified

 

By: Unknown On 1:38 PM

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Linux Basic Interview Questions - Part3

1. When you create a new partition, you need to designate its size by defining the starting and ending _____________.
 

Answer: cylinders
 

When creating a new partition you must first specify its starting cylinder. You can then either specify its size or the ending cylinder.

2. What key combination can you press to suspend a running job and place it in the background?
 

Answer: ctrl-z
 

Using ctrl-z will suspend a job and put it in the background.

3.The easiest, most basic form of backing up a file is to _____ it to another location.
 

Answer: copy
The easiest most basic form of backing up a file is to make a copy of that file to another location such as a floppy disk.

4. What type of server is used to remotely assign IP addresses to machines during the installation process?
A) SMB
B) NFS
C) DHCP
D) FT
E) HTTP
Answer: C 

You can use a DHCP server to assign IP addresses to individual machines during the installation process. Answers a, b, d, and e list legitimate Linux servers, but these servers do not provide IP addresses. The SMB, or Samba, tool is used for file and print sharing across multi-OS networks. An NFS server is for file sharing across Linux net-works. FTP is a file storage server that allows people to browse and retrieve information by logging in to it, and HTTP is for the Web.

5. Which password package should you install to ensure that the central password file couldn't be stolen easily?
A) PAM
B) tcp_wrappers
C) shadow
D) securepass
E) ssh
Answer:C 

The shadow password package moves the central password file to a more secure location. Answers a, b, and e all point to valid packages, but none of these places the password file in a more secure location. Answer d points to an invalid package.

6. When using useradd to create a new user account, which of the following tasks is not done automatically.
Choose one:
a. Assign a UID.
b. Assign a default shell.
c. Create the user's home directory.
d. Define the user's home directory.
 Answer: c
The useradd command will use the system default for the user's home directory. The home directory is not created, however, unless you use the -m option.

7. You want to enter a series of commands from the command-line. What would be the quickest way to do this?
Choose One
a. Press enter after entering each command and its arguments
b. Put them in a script and execute the script
c. Separate each command with a semi-colon (;) and press enter after the last command
d. Separate each command with a / and press enter after the last command
Answer: c
The semi-colon may be used to tell the shell that you are entering multiple commands that should be executed serially. If these were commands that you would frequently want to run, then a script might be more efficient. However, to run these commands only once, enter the commands directly at the command line.

8. You attempt to use shadow passwords but are unsuccessful. What characteristic of the /etc/passwd file may cause this?
Choose one:
a. The login command is missing.
b. The username is too long.
c. The password field is blank.
d. The password field is prefaced by an asterisk.
Answer: c
The password field must not be blank before converting to shadow passwords.

9. When you install a new application, documentation on that application is also usually installed. Where would you look for the documentation after installing an application called MyApp?
Choose one:
a. /usr/MyApp
b. /lib/doc/MyApp
c. /usr/doc/MyApp
d. In the same directory where the application is installed.
Answer: c
The default location for application documentation is in a directory named for the application in the /usr/doc directory.

10. What file would you edit in your home directory to change which window manager you want to use?
A) Xinit
B) .xinitrc
C) XF86Setup
D) xstart
E) xf86init
Answer: B 

The ~/.xinitrc file allows you to set which window man-ager you want to use when logging in to X from that account.
Answers a, d, and e are all invalid files. Answer c is the main X server configuration file.

11. What command allows you to set a processor-intensive job to use less CPU time?
A) ps
B) nice
C) chps
D) less
E) more
Answer: B 

The nice command is used to change a job's priority level, so that it runs slower or faster. Answers a, d, and e are valid commands but are not used to change process information. Answer c is an invalid command.

12. While logged on as a regular user, your boss calls up and wants you to create a new user account immediately. How can you do this without first having to close your work, log off and logon as root?
Choose one:
a. Issue the command rootlog.
b. Issue the command su and type exit when finished.
c. Issue the command su and type logoff when finished.
d. Issue the command logon root and type exit when finished.
Answer: b
You can use the su command to imitate any user including root. You will be prompted for the password for the root account. Once you have provided it you are logged in as root and can do any administrative duties.

13. There are seven fields in the /etc/passwd file. Which of the following lists all the fields in the correct order?
Choose one:
a. username, UID, GID, home directory, command, comment
b. username, UID, GID, comment, home directory, command
c. UID, username, GID, home directory, comment, command
d. username, UID, group name, GID, home directory, comment
 

Answer: b
The seven fields required for each line in the /etc/passwd file are username, UID, GID, comment, home directory, command. Each of these fields must be separated by a colon even if they are empty.

14. Which of the following commands will show a list of the files in your home directory including hidden files and the contents of all subdirectories?
Choose one:
a. ls -c home
b. ls -aR /home/username
c. ls -aF /home/username
d. ls -l /home/username
Answer: b
The ls command is used to display a listing of files. The -a option will cause hidden files to be displayed as well. The -R option causes ls to recurse down the directory tree. All of this starts at your home directory.

15 .In order to prevent a user from logging in, you can add a(n) ________at the beginning of the password field.  

Answer: asterick
If you add an asterick at the beginning of the password field in the /etc/passwd file, that user will not be able to log in.

By: Unknown On 11:01 AM

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Linux Basic Interview Questions - Part2

1. What account is created when you install Linux?
 

root

Whenever you install Linux, only one user account is created. This is the superuser account also known as root.

2. What command should you use to check the number of files and disk space used and each user's defined quotas?

repquota

The repquota command is used to get a report on the status of the quotas you have set including the amount of allocated space and amount of used space.

In order to run fsck on the root partition, the root partition must be mounted as
readonly
You cannot run fsck on a partition that is mounted as read-write.

3. In order to improve your system's security you decide to implement shadow passwords. What command should you use?   

pwconv
The pwconv command creates the file /etc/shadow and changes all passwords to 'x' in the /etc/passwd file.

4. Bob Armstrong, who has a username of boba, calls to tell you he forgot his password. What command should you use to reset his command?
 

passwd boba
The passwd command is used to change your password. If you do not specify a username, your password will be changed.

5. The top utility can be used to change the priority of a running process? Another utility that can also be used to change priority is ___________?
 

nice
Both the top and nice utilities provide the capability to change the priority of a running process.

6. What command should you type to see all the files with an extension of 'mem' listed in reverse alphabetical order in the /home/ben/memos directory.
 

ls -r /home/ben/memos/*.mem
The -c option used with ls results in the files being listed in chronological order. You can use wildcards with the ls command to specify a pattern of filenames.

7. What file defines the levels of messages written to system log files?
 

kernel.h
To determine the various levels of messages that are defined on your system, examine the kernel.h file.

8. What command is used to remove the password assigned to a group?
 

gpasswd -r
The gpasswd command is used to change the password assigned to a group. Use the -r option to remove the password from the group.

9. What command would you type to use the cpio to create a backup called backup.cpio of all the users' home directories?
 

find /home | cpio -o > backup.cpio
The find command is used to create a list of the files and directories contained in home. This list is then piped to the cpio utility as a list of files to include and the output is saved to a file called backup.cpio.

10. What can you type at a command line to determine which shell you are using?
 

echo $SHELL
The name and path to the shell you are using is saved to the SHELL environment variable. You can then use the echo command to print out the value of any variable by preceding the variable's name with $. Therefore, typing echo $SHELL will display the name of your shell.

11. What type of local file server can you use to provide the distribution installation materials to the new machine during a network installation?
 

A) Inetd
B) FSSTND
C) DNS
D) NNTP
E) NFS
 

E - You can use an NFS server to provide the distribution installation materials to the machine on which you are performing the installation. Answers a, b, c, and d are all valid items but none of them are file servers. Inetd is the superdaemon which controls all intermittently used network services. The FSSTND is the Linux File System Standard. DNS provides domain name resolution, and NNTP is the transfer protocol for usenet news.

12. If you type the command cat dog & > cat what would you see on your display? Choose one:
a. Any error messages only.
b. The contents of the file dog.
c. The contents of the file dog and any error messages.
d. Nothing as all output is saved to the file cat.

d
When you use & > for redirection, it redirects both the standard output and standard error. The output would be saved to the file cat.

13. You are covering for another system administrator and one of the users asks you to restore a file for him. You locate the correct tarfile by checking the backup log but do not know how the directory structure was stored. What command can you use to determine this?
 

Choose one:
a. tar fx tarfile dirname
b. tar tvf tarfile filename
c. tar ctf tarfile
d. tar tvf tarfile
d
The t switch will list the files contained in the tarfile. Using the v modifier will display the stored directory structure.

14. You have the /var directory on its own partition. You have run out of space. What should you do? Choose one:
 

a. Reconfigure your system to not write to the log files.
b. Use fips to enlarge the partition.
c. Delete all the log files.
d. Delete the partition and recreate it with a larger size.
d
The only way to enlarge a partition is to delete it and recreate it. You will then have to restore the necessary files from backup.

15. You have a new application on a CD-ROM that you wish to install. What should your first step be?
 

 Choose one:
a. Read the installation instructions on the CD-ROM.
b. Use the mount command to mount your CD-ROM as read-write.
c. Use the umount command to access your CD-ROM.
d. Use the mount command to mount your CD-ROM as read-only.
d
Before you can read any of the files contained on the CD-ROM, you must first mount the CD-ROM.

By: Unknown On 5:05 PM

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