Running Prefect Server without Docker ?

[Kaash]

Hi Team,

My company is looking at automation tools and as part of that we're reviewing Prefect. One of the restrictions we have is that we can't use Docker in our systems which the Prefect Server has a dependency on as you know.

Hoping you can help clarify if it would be possible to run without Docker and if so how?

Many Thanks, Kaashif Khawaja

[jcrist]

Hi @Kaash, there's nothing about server that relies on running inside docker specifically (as far as I know), but we also don't provide a nice way to run it outside docker. Prefect Server consists of several services - the easiest way we could provide users tooling for setting this up was through a dockerized setup. There might be some changes in our deployment story for Server in the coming months, but in the near future I don't believe this is something that we'll work on on our side of things. That said, if you can standup all the services in this docker-compose file, things should work the same as they would normally in docker.

Alternatively, if you'd be comfortable using Prefect Cloud instead, you can use Prefect Cloud to externally manage the things Prefect Server would, and use a local agent to execute flow runs without docker.

[Kaash]

@jcrist thank you very much for your response. We've been taking a look at getting Prefect Server running in my company using Kubernetes as standalone services and have made relatively good progress.

We do however have a few questions:

Services required by the Prefect server are set-up to run on localhost. In my company, we have a distributed network of Virtual machines across various data centres so we would need to ensure services are isolated and can independently run with their own IP address. Is this possible? We've modified references to localhost in the docker-compose file before running through "Kompose" to allow us to run in Kubernetes but references to localhost exist in the UI JS code too.

Will running the services via docker resolve the above problem? As mentioned previously, we have a limitation of using Docker (which we are trying to figure out if there is a way around) and so for completeness it would be good to understand if this gets around our issue?

Finally, are we trying to use the Prefect server in a way it wasn't designed? If so, is Prefect Cloud the way forward?

Thanks, Kaash

[zdhughes]

Hi @Kaash!

While there's nothing that requires Prefect Server to be run in Docker, spinning it up via docker-compose is our currently supported method of deploying Prefect Server. If you run into any hard-coded localhost references you'd like to template out, we'd definitely welcome a PR back to the repo! And if your issues are specifically with the UI's localhost references, this script may be useful!

As for whether you're trying to use Prefect Server in a manner it wasn't designed for, I can't immediately say. You'll likely be able to spin it up without Docker, but it'll require customization outside of our standard deploy strategy and we may not be able to offer support. If you're open to using Cloud, I'd strongly recommend it. Aside from the fact that it side-steps the Docker issue, Cloud also avoids some of the networking and infrastructure issues folks encounter while deploying Server to a remote environment. We even have a free developer tier, so you can assess whether Prefect works well within your organization's restrictions.

[jcrist]

Hi @Kaash, I'll second everything @zdhughes said.

Also - we had a livestream last week on deploying server (recording here). Note that there was a brief discussion on why docker is used currently and our feelings about deploying via other methods here in the video.

[Kaash]

Hey guys, thank you so much for your advice and sharing the video - it proved helpful!

A bit of a status update where i'm at with deploying Prefect with Kubernetes:

• Converted docker-compose to deployment/service files via Kompose. Created separate pods for the images.
• Created ingress files to expose end-points (UI, Hasura, GraphQL and PostGres)
• The UI and Hasura services are up and running - I can access the end-points.

I am however running into a few issues - notably around the theme of networking - and was hoping you maybe able to help? Alternatively, is there any guide for setting up Prefect in Kubernetes that I can follow?

• The Prefect UI -> API Status displays http://localhost:4200/graphql however I've modified /.prefect/config.toml by changing server "endpoint" as well as "graphql_url" in server.ui to the new Graphql URL i've exposed (via Ingress) however I notice the UI does not update. Is there anything else I need to update ?
• This script is great but I note that we need sudo access which we lack in work environment. Is there a way to copy the code to a different location?
• I'm struggling to get Apollo running running in my new environment. Again I think this is network related (connection to GraphQL fails) so completely understand if you feel it's for me to figure out. At this keen for any feedback!

As always, really appreciate your help with this so far.

Many thanks, Kaash

[K3UL]

Hi @Kaash, I am currently on the same path as you, looking for an automation tool that we can use in my team. Globally I hit the same wall as you with a small nuance, I can use Docker. But I would like to deploy to Kubernetes and go from the docker-compose to a Deployment. I would also like to use a pre-existing PG database and handle the localhost references.

Is there a chance you can share your work on the K8S part ?

[mingfang]

Hi,

I've created a set of Terraform modules to run Prefect Server in Kubernetes. https://github.com/mingfang/terraform-k8s-modules/tree/master/examples/prefect

It runs all the services include Prefect server, scheduler, apollo, ui, agent, hasura and postegres. I used nginx as a trick to get the UI to talk to apollo.

Please feel free to PM me to discuss.

--ming