RHEL7CentOS7 - Installation, Configuration & Management

5 Tools to Enable Remote Desktop Access on RHEL/CentOS 7 This article I will show you, tools which enabled you to access remote Desktop on machines running Centos/RHEL. All these apps works in client-server mode. So you need to run server side app on your remote machine and after that, you will be able to connect to it from all over the world. Of Course in this reference manual I will tell you how to configure this securely, so only you can access to your server. Before beginning, you only need SSH access to your server and rights to install software. You need to know root password or permissions to use sudo. All commands will work on every CentOS server 5/6/7. Before start you need to install desktop environment to your server #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 nee...

Use SSH Keys with PuTTY on Windows Introduction SSH can handle authentication using a traditional username and password combination or by using a public and private key pair. The SSH key pair establishes trust between the client and server, thereby removing the need for a password during authentication. While not required, the SSH private key can be encrypted with a passphrase for added security. The PuTTY SSH client for Microsoft Windows does not share the same key format as the OpenSSH client. Therefore, it is necessary to create a new SSH public and private key using the PuTTYgen tool or convert an existing OpenSSH private key. Requirements PuTTY SSH client for Microsoft Windows Remote server accessible over OpenSSH Install PuTTY and PuTTYgen Both PuTTY and PuTTYgen are required to convert OpenSSH keys and to connect to the server over SSH. These two tools can be downloaded individually or, preferably, as a Windows installer from the  PuTTY Download Page . ...

Install Fail2ban on Centos 7 to Protect SSH via firewalld Introduction If you are using password based authentication for SSH access to a server attached to the public internet, then this will look all too familiar. tutorial@<redacted>'s password: Last failed login: Mon Mar 20 20:47:43 UTC 2017 from 116.31.116.37 on ssh:notty There were 96619 failed login attempts since the last successful login. Last login: Mon Mar 13 18:07:23 2017 from <redacted> Did you notice the  96619  failed login attempts? The vast majority of those attempted connections are likely attempts to  guess  the credentials and gain access to your server! One way to minimize the chances of such brute-force attempts actually working is to utilize Fail2ban. Fail2ban can be configured to keep an eye on various system logs and respond to failed login attempts using local firewall rules. In this tutorial we will briefly show how to get Fail2ban installed and configured to protect ...

Setting up SSH Server for Public/Private keys based Authentication (Password-less login) SSH  is a protocol to communicate a server with client in an encrypted manner. It has replaced telnet protocol, which was not at all secure at all. Almost the Linux system admins know about it because they use it to connect to Linux servers as the physical access to server is very limited. SSH is installed by default on most of the Linux distribution. & to access a server through ssh is very easy, you use following command $ ssh {Server IP address or FQDN} and then you enter the credentials. But in this tutorial we will learn to access ssh session securely with the help of Public/Private keys authentication aka password-less ssh sessions. Advantages of using Public/Private keys authentication are You won’t be asked for password everytime you access server (unless you are using a passphrase to decrypt the keys) No-one can gain unauthorized access to your server unless they ...

Ultimate guide to securing SSH sessions I n this tutorial we will be discussing some ways with which we make our ssh server more secure. OpenSSH is currently used by default to work on servers as physical access to servers is very limited. We use ssh to copy/backup files/folders, to remotely execute commands etc. But these ssh connections might not be as secure as we believe & we must make some changes to our default settings to make them more secure. Here are steps needed to secure our ssh sessions, Use complex username & password This is first of the problem that needs to be addressed, I have known users who have ‘12345’ as their password. It seems they are inviting hackers to get themselves hacked. You should always have a complex password. It should have at-least 8 characters with numbers & alphabets, lower case & upper case letter, and also special characters. A good example would be “ vXdrf23#$wd ” , it is not a word so dictionary at...