How To Use grep Command In Linux

The grep command searches the given file for lines containing a match to the given strings or words. By default, grep prints the matching lines. grep can be used to search for lines of text that match one or many regular expressions, and outputs only the matching lines. grep Syntax grep ‘word’ filenamegrep ‘string1 string2’ […]

Building the Perfect Backtrack 4 USB Thumb Drive

This post will show you how to build a USB thumb drive with the following features: Persistent Changes Nessus and NessusClient installed Encryption configured for storing data Tools and Supplies USB thumbdrive – minimum capacity 4GB BackTrack 3 CDROM, BackTrack 4 DVD or an additional USB thumbdrive (minimum 2GB) – Used to partition the thumbdrive. Optional: […]

FREE Windows Utilities for Sniffing

WinDump WinDump is an exceptionally powerful command-line packet sniffer. Ported over from the source of the Tcpdump utility available for UNIX, WinDump carries over the same power and flexibility to the Windows world, all in a lightweight executable. WinDump is a helpful utility when you need to do some quick and easy packet capturing to […]

32 FREE Windows Administration Utilities

BareTail. A free real-time log file monitoring tool. CamStudio. Free screen recording software. CDBurnerXP. Burns CD-ROMs, DVDs, audio CDs, and ISO images. Comodo Firewall Pro. Is a firewall and antivirus application. DriveImage XML. Is a program for imaging and backing up partitions and logical drives. FileZilla. GUI FTP client. GParted LiveCD. Manages partitions on systems. […]

Get Detailed Information About Particular IP address Connections Using netstat

netstat command and shell pipe feature can be used to dig out more information about particular IP address connection. You can find out total established connections, closing connection, SYN and FIN bits and much more. You can also display summary statistics for each protocol using netstat. This is useful to find out if your server […]

Linux Upgrade Password Hashing Algorithm to SHA-512

The default algorithm for storing password hashes in /etc/shadow is MD5. I was told to use SHA-512 hashing algorithm. How do I set password hashing using the SHA-256 and SHA-512 under CentOS or Redhat Enterprise Linux 5.4? You need to use authconfig command to setup SHA-256/512 hashing. This command provides a simple method of configuring […]

Linux / UNIX Find Out What Program / Service is Listening on a Specific TCP Port

How do I find out which service is listening on a specific port? How do I find out what program is listening on a specific TCP Port? Under Linux and UNIX you can use any one of the following command to get listing on a specific TCP port: lsof : list open files including ports. […]

Understanding Linux /etc/passwd File Format

/etc/passwd file stores essential information, which is required during login i.e. user account information./etc/passwd is a text file, that contains a list of the system’s accounts, giving for each account some useful information like user ID, group ID, home directory, shell, etc. It should have general read permission as many utilities, like ls use it […]

Connecting to Amazon AWS from Windows to a Linux AMI

Connecting from Windows to a Linux Server poses problems for the average person to connect, and use their Windows OS to connect to the Linux Server. For some this is enough to put off people from jumping in, or banging their head against the wall wondering why you cannot simply RDP into the server and […]