Skip to content

Agent logs "failed to unmarshal checkin actions" error on almost every check-in #15397

Description

@macdewee

Version: 9.4.0 and later (confirmed on 9.4.3)
Operating System: Any

What's happening

Agents managed by Fleet are logging this error over and over, roughly once per check-in: failed to unmarshal checkin actions: unexpected end of JSON input

It shows up whenever Fleet Server has nothing new to tell the agent to do. It doesn't break anything — when there actually are actions to run, they still come through fine

Why it happens

In 9.4.0 we changed how the agent reads the "actions" part of Fleet's check-in response. Fleet Server leaves that field out of the response entirely when there's nothing to report, and the agent wasn't handling that case — it tried to read the missing value anyway, which is what throws the error.

Steps to reproduce

  1. Enroll an agent with Fleet.
  2. Leave it running with no pending actions.
  3. Watch the agent logs — the error shows up on almost every check-in.

Metadata

Metadata

Assignees

Labels

Type

No type

Fields

No fields configured for issues without a type.

Projects

No projects

Milestone

No milestone

Relationships

None yet

Development

No branches or pull requests

Issue actions