[REQUEST]: Create a known issue in fleet-server 8.12.0 and 8.12.1

[juliaElastic]

Description

We found an issue with fleet-server 8.12.x: agents upgraded to 8.12.0 are stuck in non-upgradeable state, so the UI does not allow upgrade again to 8.12.1 and higher.

This is due do a bug introduced in 8.12.0 fleet-server where the agent last upgraded time (upgraded_at field) keeps incorrectly being updated on every checkin.

A fix is raised and planned for 8.12.2 and 8.13.0.

As a workaround, we suggest users to use the API to upgrade those agents with the force flag.
Example:

POST kbn:/api/fleet/agents/<agent_id>/upgrade
{
  "version": "8.12.1",
  "force": true
}

POST kbn:/api/fleet/agents/bulk_upgrade
  {
    "agents": "agent.version:8.12.0",
    "version": "8.12.1",
    "force": true
  }

Resources

elastic/fleet-server#3263

Collaboration

The documentation team will investigate the issue and create the initial content.

Point of contact.

Main contact: @juliaElastic

Stakeholders: @fleet