Install Nagios from Sources in CentOS 6.X

Nagios is software monitoring. It can monitor server uptime, service, and so on. For more details, you can go here.

To install nagios, follow step below:

Set and Remove Proxy for Git

To set Proxy into git, do this step

1. Open git console
2. Type this

git config --global http.proxy http://proxyuser:proxypwd@proxy.server.com:8080
git config --global https.proxy https://proxyuser:proxypwd@proxy.server.com:8080

 Where:

• proxyuser is username for proxy
• proxypwd is proxy password for the username
• proxy.server.com is address of the proxy. It can be IP address.
• 8080 is proxy port. You can change it based on your proxy configuration

If you don't use username and password, you just need to use this format:

git config --global http.proxy http://proxy.server.com:8080
git config --global https.proxy https://proxy.server.com:8080

 If you want to unset proxy, just do this:

 git config --global --unset http.proxy
 git config --global --unset https.proxy

Import Mysql Dump into PostgreSQL Ubuntu

First, you must dump mysql with command below

mysqldump --compatible=postgresql --default-character-set=utf8 -r nama_file.sql -u root -p db_name

 If you don't need mysql password, please remove "-p"

After that, you need to convert sql into psql. You can go github repository here.

After you get psql format, than you can import with

psql -U postgres -h localhost -d database_name -f nama_file.psql

Check File With High Disk Usage On Debian / Ubuntu

In server with limited disk space, high size file is very annoying if we can not find what file it is. So this command will show you what file that has high size

find / -type f -size +10000k -exec ls -lh {} \

"/" show that it will search in the root directory and 10000k means that the file must have > 10.000k (10MB) in size. You can change it based on your need.

Source:
http://www.cyberciti.biz/faq/find-large-files-linux/

Change Hostname Permanently CentOS 6.5

To change hostname permanently, you need to do this

• nano /etc/sysconfig/network
• Change "HOSTNAME=yourNewDesiredHostname"

And the next step is

• nano /etc/hosts
• Change "127.0.0.1 yourDesiredHostname.com"

Finally reboot to take effect

Source: http://unix.stackexchange.com/questions/145019/how-to-change-hostname-on-centos-6-5

Resize Multiple Image Ubuntu

If you have many big size image and want to resize into smaller size, you can resize all image with just 1 command in terminal. This tutorial take example if you have many image with .JPG extension and you want to resize 25% of the original dimension

Create Virtual Host Apache Ubuntu

Virtual host make a server can handle many domain on it. To make virtual host on apache, follow steps below. This tutorial needs prerequisite an apache installed.