Category: CentOS

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How to configure ICINGA2 Monitoring server on CentOS / RHEL 7

Before we start to configure ICINGA2 we need to ensure that LAMP is installed on our machine. SELINUX Setup view /etc/selinux/config sed -i ‘s/SELINUX=enforcing/SELINUX=permissive/g’ /etc/selinux/config reboot

How to enable and use EPEL Repo in RedHat / CentOS Linux

Red Hat Enterprise Linux 7 / CentOS 7 rpm -ivh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm yum update

How To Use Systemctl to Manage Systemd Services and Units

Introduction Systemd is an init system and system manager that is widely becoming the new standard for Linux machines. While there are considerable opinions about whether systemd is an improvement over the

How to Install MRTG with SNMP on Linux RedHat 6.5 / CentOS 6.5

Before you Install MRTG please verify apache is installed on your machine [root@mysql01 ~]# vi /etc/hosts 127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 192.168.49.19 mysql01

How to Install RHQ on CentOS 6.5

Install PosgreSQL 3.1.1. Type ‘yum install postgresql*’ making sure to include the asterisk (*) 3.1.2. Type ‘y’ when prompted (happens twice) Confirm java version 4.1.    Type ‘java –version’ 4.2.    Confirm it’s running at least 1.6 and using OpenJDK (or Oracle/Sun Java or JRockit, but NOT GNU Libgcj)

VPN CLIENT INSTALLATION on Linux

VPN INSTALLATION on Linux [root@app-01 ~]# uname -a Linux app-01 2.6.32-431.11.2.el6.x86_64 #1 SMP Tue Mar 25 19:59:55 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux [root@app-01 /]# mkdir download [root@app-01 /]# cd download/ [root@app-01 download]# ll total 0 [root@app-01 download]# mkdir vpn [root@app-01 download]# cd vpn/ [root@app-01 vpn]# ll total 0

How to verify DDOS attack with netstat command on Linux Terminal

How to verify DDOS attack with netstat command on Linux Terminal Some examples with explanation netstat -na This display all active Internet connections to the server and only established connections are included. netstat -an | grep :80 | sort

How to setup Network File Server on CentOS / Redhat with Automatic Backups — RackSpace

NFS SERVER SETUP ON CETNOS 6.5 / Redhat 6.5 / Fedora In this tutorial let us see how to install and configure NFS server and how to share files between NFS server and clients. Though i have tested these steps in Cent-OS 6.5 32 bit edition, it will work on RHEL/Fedora/ 64 bit architecture. Scenario NFS Server Operating System : CentOS 6.5 64 bit (Minimal server install) NFS Server Operating System  : CentOS 6.5 64 bit (Minimal server install) NFS Client Operating System  : CentOS 6.5 64 bit (Desktop Minimal) NFS Server IP Address              Host rackspace-nfs01: 192.168.58.152 NFS Server IP Address              Host rackspace-nfs02: 192.168.58.153 NFS Client IP Address               Host rackspace-jon: 192.168.58.154

How to recover RPMDB in RHEL / CentOS / Fedora

You can see below is the error while updating RHEL/CentOS/Fedora using yum update [root@babar rpm]# yum update rpmdb: Thread/process 8367/457660786 failed: Thread died in Berkeley DB library error: db4 error(-41638) from dbenv->failchk: DB_RUNRECOVERY: Fatal error, run database recovery error: cannot open Packages index using db3 – (-30575) error: cannot open Packages database in /var/lib/rpm CRITICAL:yum.main:…
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APACHE OPENSSL CERTIFICATE, PHP MYSQL, HTACCESS WEB DIRECTORY with SQUID WITHOUT SSL AND with SSL SETUP

APACHE+OPENSSL+CERTIFICATE+PHP+MYSQL+HTACCESS WEB DIRECTORY SQUID WITHOUT SSL AND SSL SETUP vi /etc/sysconfig/network NETWORKING=yes HOSTNAME=reverseproxy.node01 :wq!