some useful linux commands and their full forms

ACL                            Access control list.

awk                             Aho, Weinberger, and Kernighan.

BIOS                          basic input output system.

cd                               change Directory.

chmod                        change mode.

chown                        change owner.

CIFS                          common Internet File System

df                                disk free.

DHCP                        Dynamic Host Configuration Protocol.

DNS                           Domain Name System.

du                              disk usage.

ext2                            second extended file system.

ext3                            third extended file system.

ext4                            fourth extended file system.

fdisk                           fixed disk.

FTP                            File Transfer Protocol.

grep                            Global  regular expression print.

GRUB                        Grand unified Bootloader.

http                            HyperText Transfer Protocol.

ifconfig                       Interface Configuration.

IMAP                         Internet Message Access Protocol.

KVM                          Kernel Virtual Machine.

LVM                          logical volume manager.

MBR                          Master Boot Record.

mkfs                           make filesystem.

NFS                            Network file system

pop                             Post Office Protocol.

ps                                process status.

pwd                            present working directory.

rm                              remove.

RPM                          Redhat package Manger.

scp                              secure copy.

sed                              Stream Editor.

SGID                          set group id.

SMB                           Server Message Block

ssh                              Secure Shell.

su                               substitute user or switch user.

sudo                           substitute user do or super user do .

SUID                          set user id .

tar                              tape archive.

TFTP                         Trivial File Transfer Protocol.

umask                        User's File Creation Mask.

Vim                            Visual Improved

VSFTP                       very secure  File Transfer Protocol.

YUM                          Yellowdog updater modified.

Linux Command That Can Be Used To View System Info

1. arch

This command will show you the architecture of your system.

2. uname -m

This is another command to view the architecture of the system.

3. uname -r

This command is used to check the kernel version that is being used in the system.

4. dmidecode -q

This command give you the hardware components in your system.

5. hdparm-i /dev/hda

This is the command that shows the characteristics of your hard disk.

6. hdparm-tT /dev/sda

This command is used in order to conduct tests readings on hard drives.

7. cat /proc/cpuinfo

These commands can help you in getting CPU information.

8. cat / proc / interrupts

These commands are used to interrupt a process.

9. cat /proc/meminfo

This command verifies the memory usage in your system.

10. cat /proc/swaps

These commands are used in order to swap files.

11. cat /proc/version

These three commands can display the kernel version for your system.

12. cat /proc/net/dev

These four commands are used to view the network adapters and display statistics of the system.

13. cat /proc/mounts

This command shows you the mounted file system.

14. lspci-tv

If you need to view the PCI display devices then this is the command to use.

15. lsusb-tv

This is the command for displaying USB devices.

Linux Network Management

Names dnsdomainname Show the systems DNS domain name domainname Show or set the systems domain name hostname Used to show or set the name of your machine for networking nisdomainname Show or set systems NIS/YP domain name nodename Show or set the systems DECnet node name ypdomainname Show or set the system's NIS/YP domain name Network setup and commands arp This program lets the user read or modify their arp cache. dig(1) Send domain name query packets to name servers for debugging or testing. finger Display information about the system users. ftp File transfer program. ifconfig Configure a network interface. ifdown Shutdown a network interface. ifup Brings a network interface up. Ex: ifup eth0 ipchains IP firewall administration used to set input, forward, and output rules. netconf A GUI interactive program to let you configure a network on Redhat systems. netconfig Another GUI step by step network configuration program. netstat Displays information about the systems network connections, including port connections, routing tables, and more. The command "netstar -r" will display the routing table. nslookup Used to query DNS servers for information about hosts. pftp Same as ftp. ping Send ICMP ECHO_REQUEST packets to network hosts. portmap DARPA port to RPC program number mapper. Must be running to make RPC calls. rarp Manipulate the system's RARP table. rcp Remote file copy. Copies files between two machines. rexec Remote execution client for an exec server. The host uses the rexecd server. ripquery Query RIP gateways. Request all routes known by an RIP gateway by sending an RIP request. rlogin Starts a terminal session on a remote host. route Show or manipulate the IP routing table. rsh Executes command on remote host. rup Displays summary of current system status of a remote host or all hosts on the network. ruptime Show host status of local machines. rwhod System status server, maintains database used by rwho and ruptime. showmount Show mount information for an NFS server. tcpd Access control facility for internet services. Can be set up to monitor requests for Telnet, finger, ftp, exec, rsh, rlogin, tftp, talk, comsat. It filters access for these requests. tcpdchk Tcp wrapper configuration checker. tcpdump Dump traffic on a network. Prints out headers of packets that match the boolean expression. tcpdmatch Predicts how the tcp wrapper will handle a specific request for a service. Telnet User interface to the TELNET protocol, setting up a remote console session. traceroute Print the route that packets take to the specified network host. ipx_configure Tool to setup Netware access. ncpmount Netware filesystem mounting program. nprint Novell print command. pqlist Netware printer list for a given server. pserver Netware print server. slist Netware server list.

Communications commands (includes mail)

biff		Notifies the system if mail arrives and who it is from.
comsat		Biff server to receive reports of incoming mail.
expire		Used to purge old news articles.
elm		Electronic mail.
ftp		File transfer protocol.
mailx		Berkley mail program.
metasend		Interface for sending non-text mail.
nn		Net news.
pine		Program for internet news and e-mail, Can send documents, graphics, local & remote messages.
sendmail		A popular Unix, Linux mail message transfer agent.
smail		A popular mail message transfer agent which is easier to set up than sendmail.
talk		Lets two parties talk simultaneously.
telnet		Allows a user to have a login session across a network on a remote host.
tin		Net news reader.
write		Allows users to directly interact with other users via terminal number (one way at a time).