Checkup, the comic

An inspector, before anything breaks.

The same kitchen as the other comics, on a quiet day. Nothing is wrong yet, and that is exactly when an inspector walks round and writes down what could be better, and then leaves the fixing to you.

1 The inspector walks round

The checkup is an inspector who walks round while everything still works, and writes down what could be better, in three kinds: worth a look, better changed, could be tidied. No score: a number invites polishing instead of thinking.

More power than it needs: a cook with the master key to the whole building, running privileged or with the Docker socket mounted, or a cupboard of the house they can write in.

A door open to the whole street where the staff door would have done: a published port listening on every address, where 127.0.0.1 would have been enough.

2 Will it survive the night?

Will the cook be back tomorrow? No restart policy, no health check, no memory limit: counted only for cooks who have been working for a day.

Secrets where they should not be: the password written on the menu card while the sealed envelope lies right next to it, or a private key left on the counter.

Passwords stay covered: environment variables that look like secrets show as stars until you click them. Copying still gives you the real thing.

3 Your call

Every finding links to the dialog that changes it. The inspector points; you fix. The app never changes anything by itself.

This is on purpose: dismiss a finding and it stays dismissed, greyed out at the bottom where you can undo it. A list you cannot empty is a list nobody reads.

In Docker Client MX: the checkup, notes in three weights with the fix one click away, and a report to share that shows what changed since the last one.

The cheat sheet

Every picture above, in Docker words.

The inspector: The checkup
Three kinds of notes: Worth a look, better changed, could be tidied
The master key: --privileged, the Docker socket, a writable host folder
The door to the whole street: A port published on every address
Back tomorrow?: Restart policy, health check, memory limit
The password on the menu: A secret where it should not be
Stars until you click: Environment variables that look like secrets
“On purpose”: A dismissed finding
The report: Markdown or HTML, environment variables left out

Now let the inspector walk round.

Nineteen rules in three weights, the dialog that fixes each finding one click away, and nothing changed without you.

What the checkup finds →Connections, the comic →Download for Windows