Openssh server installation

Being a network administrator requires a deep knowledge about remote login protocols such as rlogin , telnet and ssh. The one I will discuss in this article is ssh , a secure remote protocol which is used to work remotely on other machines or transfer data between computers using SCP Secure Copy command.

OpenSSH is a free open source set of computer tools used to provide secure and encrypted communication over a computer network by using the ssh protocol. Many people, new to computers and protocols, create a misconception about OpenSSH , they think it is a protocol, but it is not, it is a set of computer programs that use the ssh protocol.

A main factor which has made possible for OpenSSH to be used so much among system administrators is its multi-platform capability and very useful nice features it has. The latest version is OpenSSH 6. The most important reason why should use OpenSSH tools over ftp and telnet is that all communications and user credentials using OpenSSH are encrypted, they are also protected from man in the middle attacks.

If a third party tries to intercept your connection, OpenSSH detects it and informs you about that. To install OpenSSH , open a terminal and run the following commands with superuser permissions. Open a terminal and run the following command to make a copy of the original sshd configuration file. Before we go further, we need to verify if our openssh server is working or not.

How to do that? I love working with this amazing tool on my machine, so let me show it to you. Referring to the netcat results, the ssh service is running on port 22 on my machine.

Very good! What if we want to use another port, instead of 22? We can do that by editing the sshd configuration file. Restart OpenSSH server so the changes in config file can take place by typing the following command and run netcat to verify if the port you set for listening is open or not.

Should we verify is our openssh server is listening on port 13, or not?. This verification is necessary, so I am calling my lovely tool netcat to help me do the job. To install the OpenSSH server application, and related support files, use this command at a terminal prompt:.

For information about the configuration directives used in this file, you may view the appropriate manual page with the following command, issued at a terminal prompt:. There are many directives in the sshd configuration file controlling such things as communication settings, and authentication modes.

Prior to editing the configuration file, you should make a copy of the original file and protect it from writing so you will have the original settings as a reference and to reuse as necessary.

Furthermore since losing an ssh server might mean losing your way to reach a server, check the configuration after changing it and before restarting the server:. Additionally, if an incorrect configuration directive is supplied, the sshd server may refuse to start, so be extra careful when editing this file on a remote server. SSH allow authentication between two hosts without the need of a password.

SSH key authentication uses a private key and a public key. This will generate the keys using the RSA Algorithm. At the time of this writing, the generated keys will have bits. You can modify the number of bits by using the -b option. For example, to generate keys with bits, you can do:. During the process you will be prompted for a password. Simply hit Enter when prompted to create the key.

If the permissions are not correct change them by:. In case, if we wish to remove the client or the server, then we run the below respective commands to remove them. After the installation of OpenSSH software, we can now configure it. Now, we shall set the sshd service to start on boot. This action will ensure to automatically restart the service if a reboot or power failure occurs. Here is the command that we execute in the Powershell prompt. This will start the service and set it to start automatically.

In order to allow a secure connection to our server, we need to add a firewall rule. This rule will allow inbound ssh traffic on port To verify, we type this command at the Powershell prompt. For that, we run the following command.

After having the OpenSSH server and client installed, we can now test the setup. In Windows, we execute the following command in PowerShell. If connecting for the first time, then we will be asked to confirm the connection. In Powershell, we type the below command to transfer the file to the Administrators folder on the server:. Then we enter the password when prompted for and hit enter. We will see output similar to the following information indicating the transfer percentage, transfer speed and timeframe of the transfer.

Next, in order to verify that the file is transferred successfully, we must go back to our server and type in the dir command again which lists all the files in that particular folder. As we can see, we have successfully transferred our text file. If the build of the system is older than From gpedit. This error occurs if the server is updated via WSUS. Microsoft delivers features on-demand bypassing WSUS, so we do not get them via the internal update server. Solution: Allow Windows to load optional features directly from Microsoft Update via group policy.

Also, we saw some common errors relating to OpenSSH. Never again lose customers to poor server speed! Let us help you. Your email address will not be published.