Tools to remote into Linux Environments

#yum groupinstall 'GNOME Desktop Environment' 'X Window System'

1) VNC

x11vnc – simples of this 3 methods to get remote access. VNC stands for Virtual Network Computing) is a very useful network graphics protocol
Perhaps you need to enable EPEL (Extra Packages for Enterprise Linux) repository. Run
#yum -y install epel-release
Now we can install x11vnc. This command will install server and solve all dependencies
#yum -y install x11vnc
Then we will protect server with password:
# x11vnc -storepasswd

Enter VNC password:

Verify password:

Write password to /root/.vnc/passwd? [y]/n y

Password written to: /root/.vnc/passwd
!Do not use simple password!
We ready to start server:
# x11vnc --reopen --forever -rfbauth ~/.vncpasswd &
You can check if servers started:
    #netstat -an | grep 5900

    tcp 0 0 0.0.0.0:5900 0.0.0.0:* LISTEN

    tcp6 0 0 :::5900 :::* LISTEN

    If its ok, simply try to connect to it using vncviewer.
    #yum -y install vnc
    #vncviewer YOUR_SERVER_IP
That's all! Now you have access to your desktop. After reboot just ssh again and do again
    x11vnc --reopen --forever -rfbauth ~/.vncpasswd &

2) Tigervnc server

Tigervnc - is a high-performance, platform-neutral implementation of VNC
   #yum install -y tigervnc-server
Lets copy example config and edit it:
    #cp /lib/systemd/system/vncserver@.service /etc/systemd/system/vncserver@:1.service

    #vi /etc/systemd/system/vncserver@:1.service
Example of config:
[Unit]
    Description=Remote desktop service (VNC)
    After=syslog.target network.target
    [Service]
    Type=forking
    ExecStartPre=/bin/sh -c '/usr/bin/vncserver -kill %i > /dev/null 2>&1 || :'
    ExecStart=/usr/sbin/runuser -l YOUR_NAME -c "/usr/bin/vncserver
    PIDFile=/home/YOUR_NAME/.vnc/%H%i.pid
    ExecStop=/bin/sh -c '/usr/bin/vncserver -kill %i > /dev/null 2>&1 || :'
    [Install]
    WantedBy=multi-user.target
Now enable autostart service and restart it:
    systemctl enable vncserver@:1.service
    systemctl restart vncserver@:1.service
And finally connect to it:
    #vncviewer YOUR_SERVER_IP

3) XRDP

xrdp is an Open Source Remote desktop Protocol server. First of all we need to install EPEL repository and xrdp server:
    #yum -y install epel-release
    #yum -y install xrdp
Now lets start server
    #systemctl start xrdp.service 
Check if its running, and add him to autostart.
#netstat -an | grep 3389 
tcp 0 0 0.0.0.0:3389 0.0.0.0:* LISTEN
#systemctl enable xrdp.service
Thats all now you can connect to your server from any windows machine.

4) Teamviewer

Teamviewer does not exist in standard repos, so we need to install wget and download TeamViewer rpm package
    #yum -y install wget
    #wget https://download.teamviewer.com/download/linux/teamviewer.x86_64.rpm
Install it, using this command:
    #yum install teamviewer.x86_64.rpm
And set your password
    # teamviewer passwd YOUR_PASSWORD
    ok
    #systemctl start teamviewerd.service
Now you only need to get your id to connect
#teamviewer –info
  TeamViewer ID: 9XXXXXXX7
Try to connect to it using this id and password you set

5) FreeNX

FreeNX is a Remote Access solution based on enterprise class open source technologies by NoMachine. If you like exact this tool to get remote access you may upgrade to cloud version.
First of all we need to add e EPEL + nux-dextop repositories, for Centos 6:
# rpm -Uvh https://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
# rpm -Uvh http://li.nux.ro/download/nux/dextop/el6/x86_64/nux-dextop-release-0-2.el6.nux.noarch.rpm
For Centos 7
rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
# rpm -Uvh http://li.nux.ro/download/nux/dextop/el7/x86_64/nux-dextop-release-0-5.el7.nux.noarch.rpm
Install server and agent:
#yum install freenx-server nxagent 
Enable passdb authentication:
#echo 'ENABLE_PASSDB_AUTHENTICATION="1"' >> /etc/nxserver/node.conf
Now we need to create user for remote access and assign password for him:
# /usr/libexec/nx/nxserver --adduser bob 
NX> 100 NXSERVER - Version 3.2.0-74-SVN OS (GPL, using backend: not detected)
NX> 1000 NXNODE - Version 3.2.0-74-SVN OS (GPL, using backend: not detected)
NX> 716 Public key added to: /home/bob/.ssh/authorized_keys2
NX> 1001 Bye.
NX> 999 Bye

#/usr/libexec/nx/nxserver --passwd bob 
NX> 100 NXSERVER - Version 3.2.0-74-SVN OS (GPL, using backend: not detected)
New password:
Password changed.
NX> 999 Bye
Now we will install epel-repos and opennx client on your machine:
#yum install opennx
After starting opennx wizard you will be asked about session name,server address and port. Most important thing is to set your key. You need to copy key from servers /etc/nxserver/client.id_dsa.key and paste it general tab of your client session properties.