Linux
What is FSCK
What is FSCK
fsck - check and repair a Linux file system.
fsck is used to check and optionally repair one or more Linux file systems. filesys can be a device name (e.g. /dev/hdc1, /dev/sdb2), a mount point (e.g. /, /usr, /home), or an ext2 label or UUID specifier (e.g.UUID=8868abf6-88c5-4a83-98b8-bfc24057f7bd or LABEL=root). ..
Define Boot Loader
What is a boot loader
Most simply, a boot loader loads the operating system. When your machine loads its operating system, the BIOS reads the first 512 bytes of your bootable media (which is known as the master boot record, or MBR). You can store the boot record of only one ..
Define Multi User
Multi User
Computer systems that support two or more simultaneous users. All mainframes and minicomputers are multi-user systems, but most personal computers and workstations are not. Another term for multi-user is time sharing. ..
Linux File System
What is file system
A file system (sometimes written filesystem) is the way in which files are named and where they are placed logically for storage and retrieval. The DOS, Windows, OS/2, Macintosh, and UNIX-based operating systems all have file systems in which files are placed somewhere in ..
Pluggable Authentication Modules
What is PAM?
(Pluggable Authentication Modules) A programming interface that enables third-party security methods to be used in Unix. For example, smart cards, Kerberos and RSA technologies can be integrated with various Unix functions such as rlogin, telnet and ftp.
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How Linux kernal works
What is kernel?
The kernel is a program that constitutes the central core of a computer operating system. It has complete control over everything that occurs in the system.
A kernel can be contrasted with a shell (such as bash, csh or ksh in Unix-like operating systems), which ..
Steps to install qmHandle
qmHandle 1.3.0 for handling qmail
qmHandle 1.3.0 has some new features to delete actions based on sender or content found in the headers or body and tagging messages for earlier retry based on remote destination.
qmHandle is a simple program which allows you to view and manage the qmail message queue.
Download qmhandle-1.3.0.tar.gz ..
Installation of single SSL certificate for multiple domains
Steps to Install of single SSL certificate for multiple domains
We can Install a single Certificate for multiple domains if the certificate is a UCC certificate. It is not a Shared SSL Certificate it is a dedicated SSL certificate.
Unified Communications Certificates (UCC) are SSL Certificates that secure
multiple domains and multiple ..
Netstat command
To find DDOS Attack
netstat -tn | grep :80 | awk '\''{print $5}'\'' | cut -f1 -d: | sort | uniq -c | sort -rn | head
The above command will print the number of hits from the a specific IP address
Top 10 Users of your system
ps -eo user,pcpu,pid,command | ..
IPTABLES-Linux-Firewalls
Use Of Iptables?
Filtering packets based on a MAC address and the values of the flags in the TCP header. This is helpful in preventing attacks using malformed packets and in restricting access from locally attached servers to other networks in spite of their IP addresses.
Firewall also keeps track of each ..
SELINUX
What is Security Enhanced LINUX
Security-enhanced Linux is a research prototype of the Linux kernel and a number of utilities with enhanced security functionality designed simply to demonstrate the value of mandatory access controls to the Linux community and how such controls could be added to Linux. The Security-enhanced Linux kernel ..
Steps to install wordpress
Follow the steps below to install wordpress:
These steps will help you to install wordpress easily, follow these simple steps one by one.
Requirements:
1. PHP version 4.2 or greater
2. MySQL version version 4.0 or greater
3. The Apache mod_rewrite module
Setup your MySQL database from within your control panel and note the
followings to ..
How to find gateway ip address of my machine?
To find gateway IP address
netstat -ar
/sbin/route
Both the command will print the same result.
Output:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 ..
Search hidden characters in vi editor
How will find and and replace the hidden characters in vi editor
Vi editor is such an awesome editor for developers. while you do coding with other editors it may help you with auto syntax but the garbage values written by it while saving the file may make your ..
Find ^M / ctrl+M character in a file
To find files which control M characters use the following method.
grep -R ^M *
How to type ^M ?
Type using ctrl+v+m or just "^" + m
Ctrl+v will get you the ^ character.
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