Linux How To: Install IPTABLES in CentOS 7 / RHEL 7 Replacing FirewallD

CentOS 7 / RHEL 7 doesn’t come with iptables by default. It uses a full functional firewall system called ‘firewalld’. I have been a big fan of iptables and it’s capability from the very first, and since I have switched to CentOS 7, I couldn’t stop using it. I had to stop firewalld and install iptables in all of my CentOS 7 installation and start using iptables rules as I was using before. Here is a small How To guide on installing Iptables and disabling firewalld from a CentOS 7 or RHEL 7 or a similar variant distro.

How to Install IPTABLES in CentOS 7

To begin using iptables, you need to download and install iptables-service package from the repo. It isn’t installed automatically on CentOS 7. To do that, run the following command:

# yum install iptables-services -y

How to stop the firewalld service and start the Iptables service

Once the iptables-serivces package is installed, you can now stop the firewalld and start the iptables. Keeping both kind of network filtering too can create conflicts and it is recommended to use any out of two. To do that run the following:

# systemctl stop firewalld
# systemctl start iptables

Now to disable firewalld from the starting after the boot, you need to disable the firewalld:

# systemctl disable firewalld

To disallow starting firewalld manually as well, you can mask it:

# systemctl mask firewalld

Now you can enable iptables to start at the boot time by enabling iptables using systemctl command:

# systemctl enable iptables

How to check status of iptables in centOS 7

In previous distros, iptables status could be fetched using service command, although, the option is no longer available in CentOS 7. To fetch the iptables status, use the following:

# iptables -S

Iptables save command can still be used using service tool:

# service iptables save

This would save your iptables rules to /etc/sysconfig/iptables as it used to do in previous distros.

How to install fusecompress in CentOS 6

What is fusecompress?

FuseCompress provides a mountable Linux filesystem which transparently compresses its content. Files stored in this filesystem are compressed on the fly and FUSE allows to create a transparent interface between compressed files and user applications. FuseCompress supports different compression methods: LZO, gzip, bzip2, and LZMA.

How to install fusecompress in CentOS 6?

Follow the following to install fusecompress in CentOS 6

Install pre-tools

# yum groupinstall 'Development Tools'
# yum install boost boost-devel boost141-iostreams
# yum install fuse fuse-devel zlib-devel bzip2-devel lzo-devel
Download and Install fusecompress using git
# git clone git://github.com/tex/fusecompress.git
# cd fusecompress
# ./configure --with-z --with-bz2 --with-lzo2 --without-lzma --with-boost-serialization=boost_serialization --with-boost-iostreams=boost_iostreams --with-boost-program-options=boost_program_options --with-boost-file --with-boost-filesystem=boost_filesystem
# make
# make install

How to install node.js in a shared cpanel hosting account

What is node.js?

Node.js is event-driven, asynchronous I/O server-side JavaScript environment based on V8 engine.

Pre-Requirements

You don’t need full root access to install node.js in a cpanel hosting account. Although, you require to have access to the following from your hosting provider:

1. Compiler Access
2. SSH Access
3. An open port
4. Automatic Process Killing Exclusion

You need to first contact your provider to ensure you can access ‘1’ & ‘2’. In case 3 and 4, mention the port you want to use for your node.js app. Provider will exclude the port and your cpanel username in the firewall.

Installation: Step 1

First, find out if you have python 2.6 or above and bzip2-devel installed in the server. You can do using the following commands:

# which python
/usr/bin/python
# python -V
Python 2.6.6
# rpm -qa|grep bzip2-devel
bzip2-devel-1.0.5-7.el6_0.x86_64

Most of the latest cPanel server will have Python 2.6.6 or 2.6.7. So, as long as your provider isn’t running some old version of cPanel. If you have Python 2.6, you don’t need to recompile python. Python in cPanel server executable by the users. You might not see bzip2-devel installed. In case, it is not, your provider would need to install it using yum.

# yum install bzip2-devel

Step 2

Once the above ‘Step 1’ things are available, you can download the latest node.js binary and compile it. While writing this tutorial, node.js is running 0.10.24. You can download the latest node.js source from here:

http://nodejs.org/download/

# wget http://nodejs.org/dist/v0.10.24/node-v0.10.24.tar.gz
# tar -xvzf node-v*
# cd node*
# ./configure --prefix=$HOME
# make
# make install

Out of all the commands above, you need to note the ‘prefix’. It should use $HOME if you are running from the user’s shell. A root user can use the path to the home directory of the cpanel user like /home/cpanelusername in place of $HOME to install node.js in a cpanel user’s account.

Step 3

If you have installed node.js from the root account, change the permission for /home/cpanelusername/bin, /home/cpanelusername/include, /home/cpanelusername/lib to the cpanelusername.

# cd /home/cpanelusername
# chown -Rf cpanelusername:cpanelusername node* bin include lib

Now you can run a node.js node. A simple script to open a port can be the following:

# nano sock.js

Insert the following:

var net = require(‘net’);
var server = net.createServer(function (socket) {
socket.write(‘Open Serverrn’);
socket.pipe(socket); });
server.listen(674, ‘203.20.20.20);
console.log(‘Server running at http://203.20.20.20:674/’);

Now you can run the node as following:

# node sock.js