Terminal User Interface

The Terminal User Interface (TUI) is a command line shell that lets users sign in to the Minion Appliance and perform tasks using a text-based interface. These tasks include the following:

Reboot the system.
Change the admin password.
Configure the network address.
Update system settings.
Run a health check.
List running containers and images.
Display logs.
Open a shell.
Configure SNMP settings.

The TUI is particularly useful for setting up an appliance when you do not have DHCP, and for verifying that everything runs correctly after installation and setup.

First-time sign in

To sign in to the TUI for the first time, you must use the admin account and its default password:

Username: admin
Password: opennms

After logging in, you are prompted to change the password for the admin account to a secure one.

TUI tasks

After you sign in, the screen displays a numbered list of tasks that you can complete in the TUI. To complete a task, type the number associated with the task and follow the prompts.

Terminal User Interface displaying a numbered list of tasks.

List of TUI tasks

Reboot the system

To reboot a Minion Appliance using the TUI, type the number associated with Reboot the System and type Y to confirm. The Minion Appliance is rebooted.

Type N to cancel the reboot request and return to the list of tasks.

The Minion Appliance takes approximately 2-5 minutes to reboot (about 2.5 minutes until you can SSH into it).

Change admin password

To change the admin account’s password in the TUI, type the number associated with Change Admin Password and follow the prompts.

When you create a new password, you are asked to verify it. If the password you type when verifying does not match the new password, the TUI prompts you that they do not match, and does not change the password.

Configure network address

By default, the Minion Appliance is assigned a dynamic IP address as necessary. You can configure its network address to use a static IP, as desired.

To configure the network address in the TUI, type the number associated with Configure Network Address. Type the network interface name to configure it. This is expected to be in one of the following forms: eth*, eno*, or enp*. The Minion Appliance’s current network settings are displayed:

TUI displaying current network address configuration settings.

Follow the prompts to finish configuring your network address settings.

Update system settings

To update your Minion Appliance’s system settings using the TUI, type the number associated with Update System Settings. You can update the hostname, enable or disable secure NTP, change the NTP server, and update the HTTP and HTTPS proxy settings. Follow the prompts as appropriate.

Change default clock synchronization

The Minion Appliance uses NTS and NTP for network time synchronization, ensuring that the Minion Appliance’s clock is synchronized with that of the OpenNMS Meridian instance by regularly communicating with a secure NTP server.

NTS and NTPv4 are active by default, and are set to synchronize with time.cloudflare.com. You can disable NTS and choose to use only NTP. We recommend against this, however, because of the security enhancements that NTS provides.

To configure or update your NTP settings, type the number associated with Update System Settings and follow the prompts. The TUI displays the updated NTP server address and its synchronization status ("Synchronized" or "Not synchronized"):

TUI displaying the main task list and network connection information; the synchronization status is circled in red.

Troubleshoot NTP server synchronization

It is important that the OpenNMS Portal be properly synchronized with the NTP server. If it falls out of sync, the Minion Appliance will not communicate with your Meridian instance properly, and alerts or notifications may be generated incorrectly.

You cannot change NTS/NTP configuration in the Portal. You can, however, view its status under Appliance Details.

If the OpenNMS Portal is not synchronized with the NTP server, your firewall may be blocking the ports, or your gear may not be syncing properly. Troubleshoot the NTP server connection by checking the following:

Run a health check and address any identified failure points.
Check your firewall rules.
Check your environment’s communication capabilities by disabling secure NTP (if active) and changing the NTP server to one that you know works (for example, time.cloudflare.com).

Run a health check

To run a health check in the TUI, type the number associated with Run Health Check and follow the prompts. Results are displayed and updated in real-time:

List containers and images

To list all running containers and images in the TUI, type the number associated with List Containers and Images. The Minion Appliance’s Docker containers and images are displayed:

TUI displaying running Docker containers and images.

Note that the Minion Appliance hosts the last two software images that were used, but only the most recent one is run. When the Minion Appliance downloads a new image, the oldest is removed and replaced with the one that was previously running.

Display logs

To display your Minion Appliance’s logs in the TUI, type the number associated with Follow Logs. The most recent log files are displayed. To exit the logs and return to the TUI menu, press Ctrl+C.

Open a shell

To open a command terminal in the TUI, type the number associated with Open a Shell. The terminal runs Linux-based commands. To exit and return to the TUI menu, type exit or press Ctrl+D.

Configure SNMP

To set the SNMP location and contact name, type the number associated with Configure SNMP and follow the prompts.