rook VS sealed-secrets

I have some experience with Ceph, both for work, and with homelab-y stuff.

First, bear in mind that Ceph is a distributed storage system - so the idea is that you will have multiple nodes.

For learning, you can definitely virtualise it all on a single box - but you'll have a better time with discrete physical machines.

Also, Ceph does prefer physical access to disks (similar to ZFS).

And you do need decent networking connectivity - I think that's the main thing people think of, when they think of high hardware requirements for Ceph. Ideally 10Gbe at the minimum - although more if you want higher performance - there can be a lot of network traffic, particularly with things like backfill. (25Gbps if you can find that gear cheap for homelab - 50Gbps is a technological dead-end. 100Gbps works well).

But honestly, for a homelab, a cheap mini PC or NUC with 10Gbe will work fine, and you should get acceptable performance, and it'll be good for learning.

You can install Ceph directly on bare-metal, or if you want to do the homelab k8s route, you can use Rook (https://rook.io/).

Hope this helps, and good luck! Let me know if you have any other questions.

Another option is to leverage a Kubernetes-native distributed storage solution such as Rook Ceph as the storage backend for stateful components running on Kubernetes. This has the benefit of simplifying application configuration while addressing business requirements for data backup and recovery such as the ability to take volume snapshots at a regular interval and perform application-level data recovery in case of a disaster.

This is beyond your question but might help someone else: I switch from docker-compose to kubernetes for my home lab a while ago. The storage solution I've settled on is Rook. It was a bit of up-front work learning how to get it up but now that it's done my storage is automatically managed by Ceph. I can swap out drives and Ceph basically takes care of everything itself.

The stumbling point I am at is I want to use rook.io(Ceph) as my storage solution for the cluster. The Ceph prerequisites are one of the following:

Have you looked at Rook?

I've briefly run ceph in an external mode, you can actually use a rook deployment to manage it (sort of). Here is the documentation for doing that. For me it didn't pass my testing phase because I need better networking equipment before I can try that.

This article explains the data corruption issue happened in Rook in 2021. The root cause lies in an unexpected place and can also occurs in all Ceph environment. It's interesting that Rook had started to encounter this problem recently even though this problem has existed for a long time. It's due to a series of coincidences. I wrote this article because the word "Atari" used in a non-historical context in 2021.

Rook (this is a nice article for Rook NFS)

Storage: Favor any distributed storage you know to start with for Persistent Volumes: Ceph maybe via rook.io, Longhorn if you go rancher etc

I've dealt with a lot of issues that are very close to just unplugging a node. Unfortunately on node lost, my stateful workloads using rook-ceph block storage won't migrate over to another node automatically due to an issue with rook. Stateless apps (ingress nginx, etc..) not using rook-ceph block failover to another node just fine. I've kind of accepted this for now and I know Longhorn has a feature that makes this work but I find rook-ceph to be more stable for my workloads.

External-Secrets Operator : A Kubernetes operator that integrates external secret management systems like AWS Secrets Manager, HashiCorp Vault, Google Secrets Manager, and many more. The operator reads information from external APIs and automatically injects the values into a Kubernetes Secret (Alternatives : Vault, SOPS, Sealed Secrets)

I like sealed secrets (https://github.com/bitnami-labs/sealed-secrets) a lot. It's like 1Password, but for apps in kubernetes. You only need to secure a private key, and can throw encrypted secrets in a public github repo or anywhere you want.

It's owned by VMware (Broadcom) now, so you have to decide which company you hate more.

If you have noticed, you are setting secrets in plain text on the application-configmap.yml file, which is not ideal and is not a best practice for security. The best way to do this securely would be to use AWS Secrets Manager, an external service like HashiCorp Vault, or Sealed Secrets. To learn more about these methods see the blog post Shhhh... Kubernetes Secrets Are Not Really Secret!.

Yeah documentation is hard and I'm guilty (as a former maintainer of SealedSecrets)

SealedSecrets was designed with "write only" secrets in mind.

Turns out a lot of people need to access the current secrets because they need to update a part of a "composite" secret.

There are two kinds of "composite" secrets, one easy and one harder, but if you don't know how to do it, even the easier is hard:

1. Secret with multiple data "items" (also called keys in K8s Secret jargon but that's confusing when there is encryption involved). I.e. good old "data":{"foo": "....", "bar": "..."}

2. Secrets where data within one item is actually a config file with cleartext and secrets mixed up in one single string (usually some JSON or YAML or TOML)

Case 1 is "easy" to deal with once you realize that sealed secrets files are just text files and you can just manually merge and update encryoted data items. We even created a "merge" and some "raw" encryption APIs to make that process a little less "copy pasta" but it's still hard to have a good UX that works for everyone.

Case 2 is harder. We did implement a data templating feature that allows you to generate a config file via a go-template that keeps the cleartext parts in clear and uses templating directives to inject the secret parts where you want (referencing the encrypted the items)

The main problem with case 2 is that it's undocumented.

The feature landed in 2021:

https://github.com/bitnami-labs/sealed-secrets/pull/580

I noticed that people at my current $dayjob used sealed secrets for years and it took me a while to understand that the reason they hated it was that they didn't know about that fundamental feature.

And how to blame them!? It's still undocumented!

In my defense I spent so much effort before and after I left VMware to lobby so that the project got the necessary staffing so it wouldn't die of bitrot that I didn't have much time left to work on documentation. Which is a bit said and probably just an excuse :-)

That said, I'm happy that the project is alive and the current maintainers are taking care of it against the forces of entropy. Perhaps some doc work would be useful too. Unfortunately I don't have time for now.

This might be OT, and forgive me, but I think one of the best practices for Encrypting and Managing secrets in Kubernetes is to use Sealed Secrets, they allow your secrets to be securely stored in git with the rest of the configuration and yet no one with access to the Git repository will be able to read them. I say this might be OT, because Sealed Secrets are trying to mitigate a different threat, the threat of the secrets at rest somewhere, and not "live in the cluster", where in theory all the ingredients to decrypt the secrets would still live.

The addition of Consul and Vault gives me a few things. For one, right now I'm handling secrets with a mixture of SOPS and Sealed Secrets. I use Vault in my professional life, and have used both Vault and Consul at my last job. Vault is a beast, so I may as well get better at it; plus its options for secret injection are better.

Use Sealed Secrets Operator.

sealed-secrets (sealed)