SSH

How to find the OpenSSH version

Searching for the installed version of OpenSSH? Here are some commands to discover what software you are running.

Summary of How to find the OpenSSH version

SSH or Secure Shell is a popular protocol for doing system administration on Linux systems. Sometimes you may need to know what version you are running to know if some specific configuration options are available. In this article we have a look at the available options. Local OpenSSH version The easiest way to find the installed OpenSSH version is using the ssh -V command. This works when being logged in to the system itself.

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OpenSSH security and hardening

The SSH configuration influences the security of your Linux system. This guide helps you to secure your OpenSSH server and client configuration.

Summary of OpenSSH security and hardening

SSH or Secure Shell is the popular protocol for doing system administration on Linux systems. It runs on most systems, often with its default configuration. As this service opens up a potential gateway into the system, it is one of the steps to hardening a Linux system. This article covers the SSH security tips to secure the OpenSSH service and increase the defenses of the system. OpenSSH security OpenSSH is under development by the security fanatics from the OpenBSD project.

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Restrict SSH access to only allow rsync

Want to restrict SSH access to only allow rsync file synchronization? This article explains the steps and how to set it up.

Summary of Restrict SSH access to only allow rsync

Rsync is still one of the most popular tools to synchronize files between two systems. Although it has a few caveats when dealing with special files, it can do its job very well. In this explainer we will show how to use it in combination with SSH and at the same restrict SSH access to only allow the rsync job to run. In this article we refer to system01 having the original files and it wants to send them to the receiving system (system02)

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Using Ed25519 for OpenSSH keys (instead of DSA/RSA/ECDSA)

Many years the default for SSH keys was DSA or RSA. There is a new kid on the block, with the fancy name Ed25519. Let's have a look at this new key type.

Summary of Using Ed25519 for OpenSSH keys (instead of DSA/RSA/ECDSA)

Introduction into Ed25519 OpenSSH 6.5 added support for Ed25519 as a public key type. It is using an elliptic curve signature scheme, which offers better security than ECDSA and DSA. At the same time, it also has good performance. This type of keys may be used for user and host keys. With this in mind, it is great to be used together with OpenSSH. In this article, we have a look at this new key type.

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Using SSH keys instead of passwords

Linux systems are usually managed remotely with SSH, with many system administrators still using passwords. Time to switch over to SSH keys and here is how to do that.

Summary of Using SSH keys instead of passwords

Linux systems are usually managed remotely with SSH (secure shell). Still many administrators are using passwords, instead of keys. Keys not only boost security, it also makes managing systems much easier. Instead of entering your password for each server, you only have to do it once per session. When managing several systems per day, you will be wondering why you ever used password based authentication before. Generating the SSH key Depending on your desktop platform, we first have to create a key pair.

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