Bash (Bourne-Again SHell) is a Linux and Unix-like system shell or command language interpreter. It is a default shell on many operating systems including Linux and Apple OS X. Today, we’ll see how to quickly learn scripting.
If you have always used a graphic user interface like KDE or Gnome or MS-Windows or Apple OS X, you are likely to find bash shell confusing. If you spend some time with the bash shell prompt and it will be difficult for you to go back.
Here are a list of tutorials and helpful resources to help you learn bash scripting and bash shell itself.
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Source: nixCraft
For new computer or Laptop or server, I need to collect the information about its hardware. This is also useful when you need to replace a disk or memory with a vendor. In order to replace hardware you need all information in advance. In this post, I’m going to list commands that you can use to collect the hardware information.
All of the following commands are tested on Ubuntu Linux LTS 14.04, but should work with any modern distro too such as Debian or Fedora Linux.
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Source: nixCraft
Spoofing and bad address attack tries to fool the server and try to claim that packets had come from local address/network.
Following IP/netwok address are know to open this kind of attack:
Incoming source IP address is your servers IP address
Bad incoming address from following ranges:
- 0.0.0.0/8
- 127.0.0.0/8
- 10.0.0.0/8
- 172.16.0.0/12
- 192.168.0.0/16
- 192.168.0.0/16
- 224.0.0.0/3
- Your own internal server/network ip address/ranges.
Lire la suite…
Source: nixCraft
How do I find out my public IP address on the Linux and OS X Unix command line to use with my own bash shell script without using third party web site? Is there command-line option which will show my dynamic IP address on a Ubuntu or Fedora Linux?
There are many ways to find out your public IP address or wan (Wide Area Network) IP on a Linux or Unix-like operating systems such as FreeBSD, OpenBSD, NetBSD, Apple OS X, and others.
Explain IP addresses
An IP is short for Internet Protocol. It is used to identify computers or mobile devices on the Internet. Each device connected to the Internet has an IP address. IP address can be used to personalize information.
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How do I find out running processes were associated with each open port? How do I find out what process has open tcp port 111 or udp port 7000 under Linux?
You can the following programs to find out about port numbers and its associated process:
netstat – a command-line tool that displays network connections, routing tables, and a number of network interface statistics.fuser – a command line tool to identify processes using files or sockets.lsof – a command line tool to list open files under Linux / UNIX to report a list of all open files and the processes that opened them./proc/$pid/ file system – Under Linux /proc includes a directory for each running process (including kernel processes) at /proc/PID, containing information about that process, notably including the processes name that opened port.
You must run above command(s) as the root user. Lire la suite…
