Details

Starting from version 8.9.0, when Elastic Agent tries to perform an upgrade, it first verifies the binary signature with the key bundled in the agent. This process has a backup mechanism that will use the key coming from https://artifacts.elastic.co/GPG-KEY-elastic-agent instead of the one it already has.

In an air-gapped environment, the agent won’t be able to download the remote key and therefore cannot be upgraded.

Impact

For the upgrade to succeed, the agent needs to download the remote key from a server accessible from the air-gapped environment. Two workarounds are available.

Option 1

If an HTTP proxy is available to be used by the Elastic Agents in your Fleet, add the proxy settings using environment variables as explained in Proxy Server connectivity using default host variables. Please note that you need to enable HTTP Proxy usage for artifacts.elastic.co to bypass this problem, so you can craft the HTTP_PROXY, HTTPS_PROXY and NO_PROXY environment variables to be used exclusively for it.

Option 2

As the upgrade URL is not customizable, we have to "trick" the system by pointing https://artifacts.elastic.co/ to another host that will have the file.

The following examples require a server in your air-gapped environment that will expose the key you will have downloaded from https://artifacts.elastic.co/GPG-KEY-elastic-agent`.

Example 1: Manual

Edit the Elastic Agent server hosts file to add the following content:

<YOUR_HOST_IP> artifacts.elastic.co

The Linux hosts file path is /etc/hosts.

Windows hosts file path is C:\Windows\System32\drivers\etc\hosts.

Example 2: Puppet

host { 'elastic-artifacts':
  ensure       => 'present'
  comment      => 'Workaround for PGP check'
  ip           => '<YOUR_HOST_IP>'
}

Example 3: Ansible

- name  : 'elastic-artifacts'
  hosts : 'all'
  become: 'yes'

  tasks:
    - name: 'Add entry to /etc/hosts'
      lineinfile:
        path: '/etc/hosts'
        line: '<YOUR_HOST_IP> artifacts.elastic.co'