Red Hat System Administration I

Instructions

1. Log in to the servera machine as the student user and switch to the root user.

   [student@workstation ~]$ ssh student@servera
   ...output omitted...
   [student@servera ~]$ sudo -i
   [sudo] password for student: student
   [root@servera ~]#

2. Restart and reload the sshd service, and observe the results.

   1. Display the status of the sshd service. Note the process ID of the sshd daemon. Press q to exit the command.

      [root@servera ~]# systemctl status sshd
      ● sshd.service - OpenSSH server daemon
           Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
           Active: active (running) since Thu 2022-05-19 04:04:45 EDT; 16min ago
             Docs: man:sshd(8)
                   man:sshd_config(5)
         Main PID: 784 (sshd)
            Tasks: 1 (limit: 10799)
           Memory: 6.6M
      ...output omitted...

   2. Restart the sshd service and view the status. In this example, the process ID of the daemon changes from 784 to 1193. Press q to exit the command.

      [root@servera ~]# systemctl restart sshd
      [root@servera ~]# systemctl status sshd
      ● sshd.service - OpenSSH server daemon
           Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
           Active: active (running) since Thu 2022-05-19 04:21:40 EDT; 5s ago
             Docs: man:sshd(8)
                   man:sshd_config(5)
         Main PID: 1193 (sshd)
            Tasks: 1 (limit: 10799)
           Memory: 1.7M
      ...output omitted...

   3. Reload the sshd service and view the status. The process ID of the daemon does not change. Press q to exit the command.

      [root@servera ~]# systemctl reload sshd
      [root@servera ~]# systemctl status sshd
      ● sshd.service - OpenSSH server daemon
           Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
           Active: active (running) since Thu 2022-05-19 04:21:40 EDT; 52s ago
             Docs: man:sshd(8)
                   man:sshd_config(5)
          Process: 1201 ExecReload=/bin/kill -HUP $MAINPID (code=exited, status=0/SUCCESS)
         Main PID: 1193 (sshd)
            Tasks: 1 (limit: 10799)
           Memory: 1.7M
      ...output omitted...

3. Verify that the chronyd service is running. Press q to exit the command.

   [root@servera ~]# systemctl status chronyd
   ● chronyd.service - NTP client/server
        Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled; vendor preset: enabled)
        Active: active (running) since Thu 2022-05-19 04:04:44 EDT; 19min ago
     ...output omitted...

4. Stop the chronyd service and view the status. Press q to exit the command.

   [root@servera ~]# systemctl stop chronyd
   [root@servera ~]# systemctl status chronyd
   ○ chronyd.service - NTP client/server
        Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled; vendor preset: enabled)
        Active: inactive (dead) since Thu 2022-05-19 04:24:59 EDT; 4s ago
   ...output omitted...
   May 19 04:24:59 servera.lab.example.com systemd[1]: Stopping NTP client/server...
   May 19 04:24:59 servera.lab.example.com systemd[1]: chronyd.service: Deactivated successfully.
   May 19 04:24:59 servera.lab.example.com systemd[1]: Stopped NTP client/server.

5. Determine whether the chronyd service is enabled to start at system boot.

   [root@servera ~]# systemctl is-enabled chronyd
   enabled

6. Reboot the servera machine, and then view the status of the chronyd service.

   [root@servera ~]# systemctl reboot
   Connection to servera closed by remote host.
   Connection to servera closed.
   [student@workstation ~]$

   Log in as the student user on the servera machine, and switch to the root user. View the status of the chronyd service. Press q to exit the command.

   [student@workstation ~]$ ssh student@servera
   ...output omitted...
   [student@servera ~]$ sudo -i
   [sudo] password for student: student
   [root@servera ~]# systemctl status chronyd
   ● chronyd.service - NTP client/server
        Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled; vendor preset: enabled)
        Active: active (running) since Thu 2022-05-19 04:27:12 EDT; 40s ago
      ...output omitted...

7. Disable the chronyd service so that it does not start at boot, and then view the status of the service. Press q to exit the command.

   [root@servera ~]# systemctl disable chronyd
   Removed /etc/systemd/system/multi-user.target.wants/chronyd.service.
   [root@servera ~]# systemctl status chronyd
   ● chronyd.service - NTP client/server
        Loaded: loaded (/usr/lib/systemd/system/chronyd.service; disabled; vendor preset: enabled)
        Active: active (running) since Thu 2022-05-19 04:27:12 EDT; 2min 48s ago
      ...output omitted...

8. Reboot servera, and then view the status of the chronyd service.

   [root@servera ~]# systemctl reboot
   Connection to servera closed by remote host.
   Connection to servera closed.
   [student@workstation ~]$

   Log in as the student user on servera, and view the status of the chronyd service. Press q to exit the command.

   [student@workstation ~]$ ssh student@servera
   ...output omitted...
   [student@servera ~]$ systemctl status chronyd
   ○ chronyd.service - NTP client/server
        Loaded: loaded (/usr/lib/systemd/system/chronyd.service; disabled; vendor preset: enabled)
        Active: inactive (dead)
          Docs: man:chronyd(8)
                man:chrony.conf(5)

9. Return to the workstation system as the student user.

   [student@servera ~]$ exit
   logout
   Connection to servera closed.
   [student@workstation ~]$