Protect SSH Logins with SSH & MOTD Banner Messages

One of the easiest way to protect and secure SSH logins by displaying warming message to UN-authorized users or display welcome or informational messages to authorized users.

Display SSH Banner Messages

Being a system administrator whenever configure Linux servers I always use to configure a security banners for ssh logins. The banner contains some security warning information or general information. See my example banner message which I used for my all servers.

###############################################

ALERT! You are entering into a secured area! Your IP, Login Time, Username has been noted and has been sent to the server administrator!
This service is restricted to authorized users only. All activities on this system are logged.
Unauthorized access will be fully investigated and reported to the appropriate law enforcement agencies.

##################################################

There are two way to display messages one is using issue.net file and second one is using MOTD file.

issue.net : Display a banner message before the password login prompt.
motd : Display a banner message after the user has logged in.

So, I strongly recommended all system administrator to display a banner messages before allowing users to log in to systems. Just follow below simple steps to enable SSH logging messages.

Display SSH Warning Message to Users Before Login

To display Welcome or Warning message for SSH users before login. We use issue.net file to display a banner massages. Open the following file with VI editor.

# vi /etc/issue.net

Add the following banner sample message and save the file. You can add any custom banner message to this file.

###############################################################
#                                                      Welcome to InfronTech                                                           # 
#                                   All connections are monitored and recorded                                         #
#                          Disconnect IMMEDIATELY if you are not an authorized user!                    #
###############################################################

Open the master ssh configuration file and enable banners.

# vi /etc/ssh/sshd_config

Search for the word “Banner” and uncomment out the line and save the file.

#Banner /some/path

It should be like this.

Banner /etc/issue.net (you can use any path you want)

Next, restart the SSH daemon to reflect new changes.

# /etc/init.d/sshd restart
Stopping sshd:                                             [  OK  ]
Starting sshd:                                             [  OK  ]

Now try to connect to server you will see banner message

SSH Banner Messages Before Login

Display SSH Warning Message to Users After Login

To display banner messages after login, we use motd file, which is used to display banner massages after login. Now open it with VI editor.

vi /etc/motd

Place the following banner sample message and save the file.

###############################################################
#                                                   Welcome to my server                                                             # 
#                                    All connections are monitored and recorded                                       #
#                           Disconnect IMMEDIATELY if you are not an authorized user!                  #
###############################################################

Now again try to login into server you will get both the banner messages. See the screenshot attached below.

Display SSH Banner After Login

Configure Vsftpd with virtual users in Ubuntu 14.04

vsftpd is a GPL licensed FTP server for UNIX systems, including Linux. It is secure and extremely fast. It is stable. Don't take my word for it, though. Below, we will see evidence supporting all three assertions. We will also see a list of a few important sites which are happily using vsftpd. This demonstrates vsftpd is a mature and trusted solution. To configure vsftpd server with virtual users we need to enable PAM for vsftpd. apt-get install vsftpd libpam-pwdfile Now configure vsftpd to use PAM authentication vim /etc/vsftpd.conf then paste in the following listen=YES anonymous_enable=NO local_enable=YES write_enable=YES local_umask=022 local_root=/var/www chroot_local_user=YES allow_writeable_chroot=YES hide_ids=YES #virutal user settings user_config_dir=/etc/vsftpd_user_conf guest_enable=YES virtual_use_local_privs=YES pam_service_name=vsftpd nopriv_user=vsftpd guest_username=vsftpd Now create users - You can either use a data...

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