Quickzi: How To Add a Welcome Message for SSH Users

Here is a quick tip on how to add a welcome message for your SSH users.

If you want users to see a banner welcome message when connecting to your SSH server, you need to turn on the banner configuration of SSHd and then create a banner file.

Step 1:

Create a banner file that contains text you want people to see when connecting to your SSH server.

Create and open the banner file:

# vi /home/adam/banner

Add your text:

This is the banner file for Foogazi.com! Welcome!

Write the file and quit:

:wq

Step 2:

Edit sshd_config to set a default banner path.

# vi /etc/ssh/sshd_config

then add the following to the config file:

Banner /path/to/banner

Write the file and quit:

:wq

Step 3:

Restart the sshd server.

# /etc/init.d/sshd restart

Step 4:

SSH to your server and test to see if the banner is working:

# ssh adam@foogazi.com
This is the banner file for Foogazi.com! Welcome!

adam@foogazi.com's password:
#

It’s working!

Modify SSH Config To Maximize Security

SSH is a powerful remote logging protocol that took the place of telnet back in the mid-to-late 90′s. With so many people using SSH as an every day tool, it is important for server administrators to understand some ways of making the secure shell a bit more… well… secure. In this article you will learn how a few simple configuration modifications to sshd_config on your SSH server can improve the security of your SSH daemon and allow you to sleep better at night…

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Prevent users from logging into your system

If you are a system administrator who allows remote access to your server or desktop, you may want to disable certain users from logging into the system both remotely and locally. This article will explain how to prevent certain users from logging into your Linux machine via SSH (OpenSSH_4.4p1) and FTP (vsftpd 2.0.5).

First we must understand that in most cases there are two different ways an allowed user may be logging into your Linux server. Continue reading

SSH + Screen = Easy Administration

I have access to a numerous amount of Linux machines for work and personal matters. Instead of having a ton of different SSH or PuTTY windows open, each connected to a server that I administrate, I decided to use screen to connect to all of them, and manage each one in a different screen window.

Before getting into my screen configuration, its also important to note that on top of my screen setup, I have also configured SSH to authenticate via SSH keys, so I wouldn’t have to always type the password when admining from my “playbox”.

Here is how I set up SSH keys.

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