Remove docker restart policy until the docker api stabilizes

[michaelshobbs]

closes #1505

[ryan-bever]

Is it time to look into the restart policy again with docker 1.9.x out? Add a new unless-stopped restart policy (#15348) was added in 1.9.0

[josegonzalez]

If you want to replicate this by using the official docker-options plugin and letting us know if it worked, that would be A+.

[ryan-bever]

Sure, I will try that out as soon as I get a chance, it will probably be a day or two.

[josegonzalez]

cool :)

[ryan-bever]

OK, I was able to test out the docker-option --restart=unless-stopped. Based on the testing that I have performed this behaves as I would desire.

Below is a summary of my testing:
I have a test-app deployed with DOKKU_SCALE=2

    dokku docker-options:add test-app deploy --restart=unless-stopped
    sudo reboot

After setting the restart option following any reboot I would see the following behavior:

• The initial docker ps shows 4 containers up.
• After a couple of minutes it shows only the 2 expected containers up.

docker inspect showed for both containers:

"RestartPolicy": {
            "Name": "unless-stopped",
            "MaximumRetryCount": 0
        }

After causing the app to crash (process.exit(1)) each container twice:
docker inspect showed for both containers:

"RestartCount": 2

Then sudo reboot

• See reboot behavior description above.

Execute dokku ps:restart test-app 3 Times in quick succession:

• docker ps Shows 8 containers up for 1-2 minutes
• Then back down to expected 2

Then sudo reboot

• See reboot behavior description above.

Then dokku ps:stop test-app

• docker ps shows no containers running

Then sudo reboot

• This time only two containers come up.
• This is the same as doing a ps:stop and reboot with an app that does not have the restart policy.

Push new version of the test-app

• Behaves the same as the reboot behavior description above.
• docker inspect shows that the RestartPolicy is retained for both containers.

Test crash the test-app

• the containers are still restarted

Then sudo reboot

• Same reboot behavior described above

[josegonzalez]

What happens on memory-constrained systems? Can you try this on a box with 512mb ram and 512mb swap?

[michaelshobbs]

Might I suggest bringing this conversation to a new issue?

[josegonzalez]

👍