Control Character Commands
^ h
Backspace.
^ d
End text input, EOF for mail, write
(also acts as logout command).
^ w
Delete last word typed.
^ u
Delete (undo) last line typed.
^ r
Repeat last line typed.
^ s
Stop the screen from scrolling
(sometimes takes a while to be effective).
^ q
Unlock terminal screen, continue scrolling.
^ c
Interrupt running program ([Del] in System V).
^ z
Suspend running program, and […]

Introduction
As an operating system that has gained a strong market share in the server environment, firewall applications have always been important to Linux, and Linux kernels have had packet filtering since the 1.1 series.
In 1994, Alan Cox created ipfwadm, the first firewall for Linux, which was based on ipfw from BSD and was enhanced for […]

#vipw
Edit or no Edit path of Home directory & save
#vi /usr/local/etc/proftpd.conf
find line :
[…]
#DefaultRoot ~
[…]
uncomment # to
[…]
DefaultRoot ~
[…]
save file
Restart FTP deamon
/usr/local/etc/rc.d/proftpd retstart

If you forgot you password for your ubuntu system you can recover using the following stepsTurn your computer on.
Press ESC at the grub prompt.
Press e for edit.
Highlight the line that begins kernel ………, press e
Go to the very end of the line, add rw init=/bin/bash
press enter, then press b to boot your system.
Your system will […]

Some time you might find some applications are having only .rpm files but you want a .deb package for your debian,Ubuntu and other debian derived ditributions.If you can’t find .deb debian package in any of the debian,ubuntu repositories or elsewhere, you can use the alien package converter to install the .rpm file.Alien is a program […]

MySQL is a relational database management system (RDBMS) based on SQL (Structured Query Language). First released in January, 1998, MySQL is now one component of parent company MySQL AB’s product line of database servers and development tools. Yes, it really is this easy.run the following command to change the mysql root password
sudo /etc/init.d/mysql reset-password
New MySQL […]

1. Telnet using TCP port 25 :
#telnet xxx.xxx.xxx.xxx 25
or
#telnet domain.tld 25
2. Issue the following smtp command sequence
helo <your domain name><enter>
response should be as follows
250 OK
mail from: <your Email Address><enter>
response should be as follows
250 OK - mail from <your Email address>
rcpt to: <recipient address><enter>
response should be as follows
250 OK - Recipient <recipient address>
data<enter>
response should be as […]

fsck is a Unix utility for checking and repairing file system inconsistencies . File system can become inconsistent due to several reasons and the most common is abnormal shutdown due to hardware failure , power failure or switching off the system without proper shutdown . Due to these reasons the superblock in a file system […]

You can easily display dropped and total transmitted packets with netstat for eth0:
# netstat –interfaces=eth0
Output:
Kernel
Interface table Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0 1500 0 2040929 0 […]

Simply use netstat -s:
# netstat -s | less
# netstat -t -s | less
# netstat -u -s | less
# netstat -w -s | less
# netstat -s
Output:
Ip: 88354557 total packets received
0 forwarded
0 incoming packets discarded
88104061 incoming packets delivered
96037391 requests sent out
13 outgoing packets dropped
66 fragments dropped after timeout
295 reassemblies required
106 packets reassembled ok
66 […]