linux

Change hostname / domain name

Q. I would like to change hostname and domain name for my Linux server. Where can I set the local hostname and domain name of my server? A. You can use hostname command to show or set the system’s host…

Identify IP address of the router

Question: What Is the IP Address of a Router? A typical home network router keeps two IP addresses, one for local devices to connect to across the LAN, and one for the external Internet (WAN) connection. How can you find a router’s IP addresses? Answer:…

WI-FI Network Radius setup

Installing and Operating a RADIUS Server Overview Whenever access to a resource must be regulated, there must be a regulation mechanism. A RADIUS server is a mechanism for regulating access to a computer network by users (customers, usually.)…

WD disk can’t be found

[root@localhost disk]# fdisk /dev/sdb Welcome to fdisk (util-linux 2.22.2). Changes will remain in memory only, until you decide to write them. Be careful before using the write command. Command (m for help): help h: unknown command Command action a toggle…

GD, ImageMagic, mbstring installation Fedora

GD and ImageMagick are must installed components on your server if you are dealing with images in PHP, and I can’t believe that your application is not using any image processing. PHP is used to create and manipulate image files…

Top 10 Linux Virtualization Software

Virtualization is the latest buzz word. You may wonder computers are getting cheaper every day, why should I care and why should I use virtualization? Virtualization is a broad term that refers to the abstraction of computer resources such as:…

Top 5 memory consume process

$ ps -eo pmem,pcpu,vsize,pid,cmd | sort -k 1 -nr | head -5 You can also check top command, then -F and select „n“ to see process memory usage.

Too many open files error

Root causes: In most operating systems, a file is simply a chunk of data stored on disk. However, in Linux, everything is file. Besides data and executable files, directories, sockets, even different components are treated as files. Therefore max-file handle…