Linux Banner KodeKloud Engineer Task

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Linux Banner KodeKloud Engineer Task

 Question :  During the monthly compliance meeting, it was pointed out that several servers in the Stratos DC do not have a valid banner. The security team has provided serveral approved templates which should be applied to the servers to maintain compliance. These will be displayed to the user upon a successful login.


Update the message of the day on all application and db servers for Nautilus. Make use of the approved template located at /tmp/nautilus_banner on jump host


Solution:  

1.  Copy the /tmp/nautilus_banner using scp command from jumpserver to  

all Apps & DB servers.

thor@jump_host /$ ll /tmp/nautilus_banner

-rw-r--r-- 1 root root 2531 Jun 26 15:39 /tmp/nautilus_banner

thor@jump_host /$

thor@jump_host /$ scp -r  /tmp/nautilus_banner  tony@stapp01:/tmp

The authenticity of host 'stapp01 (172.16.238.10)' can't be established.

ECDSA key fingerprint is SHA256:C1wj96Q8FEfYPlCvtHftglN5KEYSvaAhbi3hmWcXF/U.

ECDSA key fingerprint is MD5:09:36:49:a3:00:da:35:72:e7:b2:2a:97:dd:f3:01:8d.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added 'stapp01,172.16.238.10' (ECDSA) to the list of known hosts.

tony@stapp01's password:

nautilus_banner                                                                            100% 2531     2.3MB/s   00:00   

thor@jump_host /$


2. Login to all the App server  & switch to root user 

    Now move copied file banner  /tmp to /etc/motd 

thor@jump_host /$ ssh tony@stapp01

tony@stapp01's password:

[tony@stapp01 ~]$ sudo su -

 We trust you have received the usual lecture from the local System

Administrator. It usually boils down to these three things:

     #1) Respect the privacy of others.

    #2) Think before you type.

    #3) With great power comes great responsibility.

 [sudo] password for tony:

 [root@stapp01 ~]# mv /tmp/nautilus_banner  /etc/motd

mv: overwrite ‘/etc/motd’? yes

[root@stapp01 ~]#


3. Validate the open new terminal and login with user 

thor@jump_host /$ ssh tony@stapp01

tony@stapp01's password:

Last login: Sat Jun 26 15:46:03 2021 from jump_host.linux-banner_app_net

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

  .__   __.      ___      __    __  .___________. __   __       __    __       _______.        #

       |  \ |  |     /   \    |  |  |  | |           ||  | |  |     |  |  |  |     /       |   #

       |   \|  |    /  ^  \   |  |  |  | `---|  |----`|  | |  |     |  |  |  |    |   (----`   #

       |  . `  |   /  /_\  \  |  |  |  |     |  |     |  | |  |     |  |  |  |     \   \       #

       |  |\   |  /  _____  \ |  `--'  |     |  |     |  | |  `----.|  `--'  | .----)   |      #

       |__| \__| /__/     \__\ \______/      |__|     |__| |_______| \______/  |_______/       #

                                                                                               #

                                                                                               #

                                                                                               #

                                                                                               #

                                 # #  ( )                                                      #

                                  ___#_#___|__                                                 #

                              _  |____________|  _                                             #

                       _=====| | |            | | |==== _                                      #

                 =====| |.---------------------------. | |====                                 #

   <--------------------'   .  .  .  .  .  .  .  .   '--------------/                          #

     \                                                             /                           #

      \_______________________________________________WWS_________/                            #

  wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww                        #

wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww                       #

   wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww                         #

                                                                                               #

                                                                                               #

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

Warning! All Nautilus systems are monitored and audited. Logoff immediately if you are not authorized!

[tony@stapp01 ~]$


Please Note :- I have showed only for stapp01
You have to do this in all app server stapp01,stapp02, stapp03.


While copying file on DB server you will faced issue due to openssh-clients package not installed.

1. Login on DB server  &  Install openssh-clients

thor@jump_host /$ ssh peter@stdb01

The authenticity of host 'stdb01 (172.16.239.10)' can't be established.

ECDSA key fingerprint is SHA256:4DArb3ojuPQXjniJ6ju3HtFHQp+PtG8CVN0qP39Lsyo.

ECDSA key fingerprint is MD5:81:1a:82:8a:53:14:a7:dd:61:49:3f:0f:59:73:47:89.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added 'stdb01,172.16.239.10' (ECDSA) to the list of known hosts.

peter@stdb01's password:

[peter@stdb01 ~]$ sudo su -

 We trust you have received the usual lecture from the local System

Administrator. It usually boils down to these three things:

     #1) Respect the privacy of others.

    #2) Think before you type.

    #3) With great power comes great responsibility.

 [sudo] password for peter:

[root@stdb01 ~]#


2.  Copy the /tmp/nautilus_banner using scp command from jumpserver 

thor@jump_host /$ scp -r  /tmp/nautilus_banner  peter@stdb01:/tmp

peter@stdb01's password:

nautilus_banner                                                                                                              nautilus_banner                                                                                                                                                            100% 2531     3.2MB/s   00:00   

thor@jump_host /$


3. Now move copied file banner  /tmp to /etc/motd 

[root@stdb01 ~]# mv /tmp/nautilus_banner  /etc/motd

mv: overwrite ‘/etc/motd’? yes

[root@stdb01 ~]#



4.  Validate  login all the server's & check banner implemented successfully as per the task request

thor@jump_host /$ ssh peter@stdb01

peter@stdb01's password:

Last login: Sat Jun 26 15:53:55 2021 from jump_host.linux-banner_db_net

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

  .__   __.      ___      __    __  .___________. __   __       __    __       _______.        #

       |  \ |  |     /   \    |  |  |  | |           ||  | |  |     |  |  |  |     /       |   #

       |   \|  |    /  ^  \   |  |  |  | `---|  |----`|  | |  |     |  |  |  |    |   (----`   #

       |  . `  |   /  /_\  \  |  |  |  |     |  |     |  | |  |     |  |  |  |     \   \       #

       |  |\   |  /  _____  \ |  `--'  |     |  |     |  | |  `----.|  `--'  | .----)   |      #

       |__| \__| /__/     \__\ \______/      |__|     |__| |_______| \______/  |_______/       #

                                                                                               #

                                                                                               #

                                                                                               #

                                                                                               #

                                 # #  ( )                                                      #

                                  ___#_#___|__                                                 #

                              _  |____________|  _                                             #

                       _=====| | |            | | |==== _                                      #

                 =====| |.---------------------------. | |====                                 #

   <--------------------'   .  .  .  .  .  .  .  .   '--------------/                          #

     \                                                             /                           #

      \_______________________________________________WWS_________/                            #

  wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww                        #

wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww                       #

   wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww                         #

                                                                                               #

                                                                                               #

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

Warning! All Nautilus systems are monitored and audited. Logoff immediately if you are not authorized!

[peter@stdb01 ~]$


5.  Click on Finish & Confirm to complete the task successful

Happy Learning!!!!

Apart from this if you need more clarity,  I have made a  tutorial video on this , please go through and share your comments. Like and share the knowledge




Post a Comment

9 Comments

  1. Make use of the approved template located at /root/nautilus_banner on jump host,....,, He is saying file in /root/nautilus but you using /tmp directory I didn't get clear about /tmp/nautilus_banner this directory you use

    ReplyDelete
    Replies
    1. Thanks for your comment. I copied the update task question for reference. which cause you confusion. If you would gone through the video you would notice in previous task location was /tmp/nautilus. Which now change to /root /nautilus_banner. Please go through the update version of task and follow the same steps.

      Delete
  2. Hello, thanks for your help. Please how do you connect to stdb server?

    ReplyDelete
  3. Done the same steps as you mentioned, even given the executable permission to /etc/motd, still it didnt work.

    ReplyDelete
    Replies
    1. hope you doing on the correct server. could you please share me task will validate. or connect me online chat while performing task . will help you.

      Delete
    2. it worked now but i have to edit /etc/ssh/sshd_config where i have to uncomment banner and need to add file path (banner one)..and restarted the sshd service.

      Delete
    3. Glad to know you solve by own and troubleshoot. Thanks for updating. Keep Learning

      Delete

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