[MESOS-6445] Reconciliation for unreachable agent after master failover is incorrect.

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: 1.1.0
• Component/s: master
• Labels: mesosphere
• Target Version/s: 1.1.0
• Assignee: Neil Conway
• Reporter: Neil Conway
• Shepherd: Vinod Kone
• Created: 21/Oct/16 19:09
• Updated: 28/Oct/16 09:31
• Resolved: 25/Oct/16 19:18

Description

    If the master fails over and an agent does not re-register within the
    `agent_reregister_timeout`, the master marks the agent as unreachable in
    the registry and sends `slaveLost` for it. However, we neglected to
    update the master's in-memory state for the newly unreachable agent;
    this meant that task reconciliation would return incorrect results
    (until/unless the next master failover).