Linux
How to Find Hardware Details with dmesg
dmesg is Linux command that is used to examine or control the kernel ring buffer. The program helps users to print out their boot-up messages. Lspci worked well to discover our PCI devices but we want inventory of all devices on the system. Using dmesg we can view hardware details of everything detected by our [...]
How to see the hardware on a linux Box
Many new Linux users have trouble determining the true specs of their Linux machine from command line. Linux GUI software’s have evolved over past few years and provide the same details in very beautiful laid out manner; however an administrator/home-user may not have luxury of those tools on every machine Task display : CPU Information [...]
How to Install SquirrelMail on Unix and Linux systems
Any version numbers used in these examples are specific to the time when this documentation was written. You should generally use the most up to date versions of all software involved. That is, if there are newer versions of these packages available now, you’ll probably want to substitute the newer numbers in the examples below. [...]
The mknod command in Linux
MAKEDEV is the preferred way of creating device files which are not present. However sometimes the MAKEDEV script will not know about the device file you wish to create. This is where the mknod command comes in. In order to use mknod you need to know the major and minor node numbers for the device [...]
How to take the output of one program and send it to another as the input In Linux
you can actually take the output of one program and send it to another as the input. This is called piping. With pipes, you can “glue” multiple commands together in a powerful way. The following is maybe one of the most common ways of using pipes: $ ls | less In the example above, the standard output [...]
How to Setup PXE under Centos
PXE is an open industry standard developed by a number of software and hardware vendors. It was initially designed by Intel, with input from several other vendors including 3Com, HP, Dell, Compaq, and Phoenix Technologies. PXE works with a network interface card (NIC) in the PC, and makes the NIC a boot device. The PXE [...]
How to Configure the firewall for https Traffic in Linux
You should now have a site working over https using a self-signed certificate. If you can’t connect you may need to open the port on your firewall. To do this amend your iptables rules: iptables -A INPUT -p tcp –dport 443 -j ACCEPT /sbin/service iptables save iptables -L -v
How to Assign Virtual IPs to your NIC
A virtual IP address (VIP or VIPA) is an IP address that is not connected to a specific computer or network interface card (NIC) on a computer. Incoming packets are sent to the VIP address, but all packets travel through real network interfaces. VIPs are mostly used for connection redundancy; a VIP address may still [...]
How to use Tcpdump Command In Linux
The tcpdump command prints out the headers of packets on a network interface that match the boolean expression. It can also be run with the -w flag, which causes it to save the packet data to a file for later analysis. It can also be run with the -r flag, which causes it to read from a saved packet file rather [...]
How to add a Static route in Linux?
Its very easy to add a static route in windows, its straight forward and will not disturb you more. But in linux the syntax is little different . Usage: inet_route [-vF] del {-host|-net} Target[/prefix] [gw Gw] [metric M] [[dev] If] Â Â Â Â inet_route [-vF] add {-host|-net} Target[/prefix] [gw Gw] [metric M] Â Â Â Â [...]
How to Capture Linux network packets to a file
tcpdump command dump traffic on a network in real time. It prints out a description of the contents of packets on a network interface. By default traffic is dumped on a screen. To capture these packets to a file, enter the following command as the root user: # tcpdump -i eth0 -w traffic.eth0 The -w flag causes it [...]
The powerful bash wildcards in Linux
Wildcards are a shell feature that makes the command line much more powerful than any GUI file managers. You see, if you want to select a big group of files in a graphical file manager, you usually have to select them with your mouse. This may seem simple, but in some cases it can be very [...]