Finding and preventing ddos attack on Linux Server

A distributed denial-of-service (DDoS) attack occurs when multiple systems flood the bandwidth or resources of a targeted system, usually one or more web servers. Such an attack is often the result of multiple compromised systems flooding...

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Tracing the execution of processes using strace

Strace is quite simply a tool that traces the execution of system calls. It can trace the execution of a binary from start to end, and output a line of text with the name of the system call, the arguments and the return value for every system call over the lifetime of the process.    1.Find out which config files a program reads on startup strace php...

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SELinux mechanism in linux environment.

Security-Enhanced Linux (SELinux) is a mandatory access control (MAC) security mechanism implemented in the kernel. SELinux was first introduced in CentOS 4 and significantly enhanced in later CentOS releases.  SELinux follows the...

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Simple bash script's for managing mysql

1. Monitoring replication health #!/bin/bash sql_thread_running=$(mysql -e "show slave status\G" | awk -F":" '/Slave_SQL_Running/ { print $2 }' | tr -d ' ') io_thread_running=$(mysql -e "show slave status\G" | awk -F":" '/Slave_IO_Running/...

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Running multiple mysql instance on single server(Centos&Red Hat)

 Follow Below Steps:- Step (1): Create a new MySQL data directory. mkdir -p /var/lib/mysql2 Step 2:  Give permission and ownership .Now we are taking ownership and permission reference from original /var/lib/mysql data directory chmod --reference /var/lib/mysql /var/lib/mysql2 chown --reference /var/lib/mysql /var/lib/mysql2 Step...

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Mysql Installation using rpm package

    1.Download the required rpm filess MySQL-client-community-5.1.25-0.rhel5.i386.rpm MySQL-server-community-5.1.25-0.rhel5.i386.rpm MySQL-devel-community-5.1.25-0.rhel5.i386.rpm    2. Remove the existing...

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Check and Repair Mysql Tables

 Check a Specific Table in a Database If your application throws an error message saying that a specific table is corrupted, execute the mysqlcheck command to check it. The following example checks t1 table in test database. # mysqlcheck...

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