Ubuntu Pro-related MOTD messages#

When the Ubuntu Pro Client (pro) is installed on the system, it delivers custom messages on “Message of the Day” (MOTD). Those messages are generated directly by three different sources.

MOTD about available updates
MOTD about important subscription conditions
MOTD about ESM being available

MOTD about available updates#

The update-notifier delivers a script via the update-notifier-common package called `/usr/lib/update-notifier/apt_check.py. With regards to Ubuntu Pro, this script is responsible for:

Informing the user about the status of one of the ESM services; esm-apps if the machine is an LTS series, or esm-infra if the series is in ESM mode.
Showing the number of esm-infra or esm-apps packages that can be upgraded on the machine.

update-notifier has always added information about potential updates to MOTD to raise user awareness. With the advent of Ubuntu Pro they are just more differentiated.

Note that if you run apt_check.py directly it might give you rather unreadable output as it is meant for program use. You can add --human-readable to see the information as it would be presented in MOTD.

Machine is unattached#

On a machine that runs an Ubuntu release for which the esm-apps service is available, but not yet attached to an Ubuntu Pro subscription, there will be a message notifying the user that there may be more security updates available through ESM Apps.

Expanded Security Maintenance for Applications is not enabled.

0 updates can be applied immediately.

Enable ESM Apps to receive additional future security updates.
See https://ubuntu.com/esm or run: sudo pro status

Machine is fully attached#

In the opposite situation, if an LTS machine has the esm-infra and esm-apps services enabled then users will see the following output in MOTD:

Expanded Security Maintenance for Applications is enabled.

11 updates can be applied immediately.
5 of these updates are ESM Apps security updates.
1 of these updates is a ESM Infra security update.
5 of these updates are standard security updates.
To see these additional updates run: apt list --upgradable

Machine is fully attached, on an older release#

Above you have seen examples of recent (as in “still in their first 5 years of support”) Ubuntu releases, where the hint is about ESM Apps extending the coverage to the universe repositories.

However, if running on an Ubuntu release that has is already past the initial 5 years of support and has thereby entered Expanded Security Maintenance (“ESM”), we would instead see esm-infra (which provides coverage for another 5 years) being shown:

Expanded Security Maintenance Infrastructure is enabled.

11 updates can be applied immediately.
5 of these updates are ESM Apps security updates.
1 of these updates is a ESM Infra security update.
5 of these updates are standard security updates.
To see these additional updates run: apt list --upgradable

Partial service enablement#

Now let’s consider a scenario where one of these services is not enabled. For example, if esm-apps was disabled, the output will be:

Expanded Security Maintenance for Applications is not enabled.

6 updates can be applied immediately.
1 of these updates is a ESM Infra security update.
5 of these updates are standard security updates.
To see these additional updates run: apt list --upgradable

5 additional security updates can be applied with ESM Apps
Learn more about enabling ESM Apps for Ubuntu 16.04 at
https://ubuntu.com/16-04

At the end of the output we can see the number of packages that could be upgraded if that service was enabled. Note that we would deliver the same information for esm-infra if the service was disabled and the series running on the machine is in ESM state.

MOTD about important subscription conditions#

One of the timer jobs Ubuntu Pro uses can insert additional messages into MOTD. These messages will be always delivered next to the content created by update-notifier. These additional messages are generated when pro detects that certain conditions on the machine have been met. They are:

Subscription expired#

When the Ubuntu Pro subscription is expired, pro will deliver the following message after the update-notifier message:

*Your Ubuntu Pro subscription has EXPIRED*
2 additional security update(s) require Ubuntu Pro with 'esm-infra' enabled.
Renew your service at https://ubuntu.com/pro

Subscription about to expire#

When the Ubuntu Pro subscription is about to expire, we deliver the following message after the update-notifier message:

CAUTION: Your Ubuntu Pro subscription will expire in 2 days.
Renew your subscription at https://ubuntu.com/pro to ensure continued security
coverage for your applications.

Subscription expired but within grace period#

When the Ubuntu Pro subscription has expired, but is still within the grace period, we deliver the following message after the update-notifier script:

CAUTION: Your Ubuntu Pro subscription expired on 10 Sep 2021.
Renew your subscription at https://ubuntu.com/pro to ensure continued security
coverage for your applications.
Your grace period will expire in 9 days.

MOTD about ESM being available#

When Ubuntu Pro became generally available, a temporary announcement was made through MOTD. This was intended to raise awareness of Pro now being available and free for personal use, and was shown on systems that could be covered by esm-apps. It looked like:

 * Introducing Expanded Security Maintenance for Applications.
   Receive updates to over 25,000 software packages with your
   Ubuntu Pro subscription. Free for personal use.

     https://ubuntu.com/pro

Since this message was intended as a limited-time announcement to coincide with the release of Ubuntu Pro into general availability, it was removed in 27.14.

How are these messages inserted into MOTD and how can I disable them?#

Just as there are different purposes to the messages outlined above, there are different sources producing these MOTD elements that one sees at login.

Those messages are considered important to ensure user awareness about the free additional security coverage provided by Ubuntu Pro and about not-yet-applied potential updates in general. Therefore it is generally not recommended to disable them. But still, you can selectively disable them by removing the config files that add them, as outlined below.

Removing those files is considered a conffile change to customize a program and they will stay removed even on future upgrades or re-installations of the related packages.

If you realize that you actually need them back you need to reinstall the related packages and tell apt/dpkg to offer you to restore those files via:

sudo apt install --reinstall -o Dpkg::Options::="--force-confask" ubuntu-advantage-tools update-notifier-common

Source: MOTD about available updates#

update-notifier-common has a hook /etc/apt/apt.conf.d/99update-notifier that runs after apt update.
That hook will update the information in /var/lib/update-notifier/updates-available matching the new package information that was just fetched by using /usr/lib/update-notifier/apt-check --human-readable.
At MOTD generation time, the script located at /etc/update-motd.d/90-updates-available checks if /var/lib/update-notifier/updates-available exists and if it does, inserts the message into the full MOTD.

If you want to disable any message of update-notifier (not just related to Ubuntu Pro and ESM) about potentially available updates remove /etc/update-motd.d/90-updates-available.

Source: MOTD about important subscription conditions#

The subscription status is checked periodically in the background when the machine is attached to an Ubuntu Pro subscription.
If one of the above conditions applies to the subscription that the machine is attached to (there are no messages generated by this for unattached machines), then the message is stored in /var/lib/ubuntu-advantage/messages/motd-contract-status.
At MOTD generation time, the script located at /etc/update-motd.d/91-contract-ua-esm-status checks if /var/lib/ubuntu-advantage/messages/motd-contract-status exists and if it does, inserts the message into the full MOTD.

If you want to disable any message about important conditions of your attached subscription remove /etc/update-motd.d/91-contract-ua-esm-status.

Source: MOTD about ESM being available#

pro checks regularly if a system would have esm-apps available to it and if so places a message in /var/lib/ubuntu-advantage/messages/motd-esm-announce.
At MOTD generation time, the script located at /etc/update-motd.d/88-esm-announce checks if /var/lib/ubuntu-advantage/messages/motd-esm-announce exists and if it does, inserts the message into the full MOTD.

If you want to disable the ESM announcement remove /etc/update-motd.d/88-esm-announce (or upgrade to 27.14 or later which will remove it for you).