How to change the ssh banner for the linux system.

Adding customized  Linux login banner on the Linux system adds protection on the legal front & also it acts as the warning information to the user. This banner is shown to the user before the user logged into the system/OS. Since by default system does not show any kind of messages to user we need to change this as per the legal policy of the organization.

So here the way we can change it.

1. Add the following line of directive in the file sshd config file “/etc/sshd/sshd_config”

banner /etc/issue.net

The above line defines the customized pre-login banner file “/etc/issue.net”.

2. Now the next step is create the customized banner in the “/etc/issue.net” file as per your organization policy. As an example I have taken below one:

[root@kalwa1 etc]# cat /etc/issue.net
################################################################
#                                                              #
# Hello , This is UXtechno's Property.                         #
# Please log Off Immediately!!!!!!                             #
# If you are not a valid user                                  # 
#                                                              #
#                                                              #
###############################################################
[root@kalwa1 etc]#

3. Now restart the sshd service:

[root@kalwa1 etc]# service sshd restart
Stopping sshd: [ OK ]
Starting sshd: [ OK ]
[root@kalwa1 etc]#

4. Now when you try to login on the system following prelogin banner will be shown as below: