nfs-subdir-external-provisioner VS litestream

Using nfs-subdir-external-provisioner instead of csi-driver-nfs

I am trying to run sonarr inside my k3s cluster. Since I have multiple nodes, in order to keep data persistant I have been using a NAS and the Kubernetes NFS external provisioner as my Storage Class.

There's this, if you want your nfs storage available to pods as PVCs, with some limitations: https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner

NFS Provisioner

Depends on how much resiliency you need . Something like https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner works well for a lab or non-prod cluster. You could even use something like this in prod if you have access to highly reliably NFS mounts.

I first installed a NFS Server via this helm chart: https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner Eventually I deployed Longhorn cause I needed expandable volumes, which the first repo doesn't support. I guess for best performance you should go for a ceph cluster, but I'm not an expert.

I used the NFS provisioner for persistent volumes until I got the Ceph side up and running. I created a share on my NAS specifically for k8s. It worked very well and had the bonus of being just a regular file system that you could browse/edit easily (just place files in or edit config). I would agree with not moving plex into k8s. I right now just have a barebones 1 control 2 worker setup using k3s.

However, is it too difficult to create new pods/deployments etc on your own? I find it super easy to just create a PVC (via https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner ) and create a MySQL pod in a new namespace for every micro service I create.

This is what you need https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner Point it to a folder and it will create subfolders for each PVC.

I have not, but I keep meaning to collate everything I've learned into a set of useful defaults just to remind myself what settings I should be enabling and why.

Regarding Litestream, I learned pretty much all I know from their documentation: https://litestream.io/

This presentation is focused on the use-case of vertically scaling a single server and driving everything through that app server, which is running SQLite embedded within your application process.

This is the sweet-spot for SQLite applications, but there have been explorations and advances to running SQLite across a network of app servers. LiteFS (https://fly.io/docs/litefs/), the sibling to Litestream for backups (https://litestream.io), is aimed at precisely this use-case. Similarly, Turso (https://turso.tech) is a new-ish managed database company for running SQLite in a more traditional client-server distribution.

This post intends to help you setup replication for SQLite using Litestream.

I've been messing around with litestream. It is so cool. And, I either found a bug in the -timestamp switch or don't understand it correctly.

What I want to do is time travel into my sqlite database. I'm trying to do some forensics on why my web service returned the wrong data during a production event. Unfortunately, after the event, someone deleted records from the database and I'm unsure what the data looked like and am having trouble recreating the production issue.

Litestream has this great switch: -timestamp. If you use it (AFAICT) you can time travel into your database and go back to the database state at that moment. However, it does not seem to work as I expect it to:

https://github.com/benbjohnson/litestream/issues/564

I have the entirety of the sqlite database from the production event as well. Is there a way I could cycle through the WAL files and restore the database to the point in time before the records I need were deleted?

Will someone take sqlite and compile it into the browser using WASM so I can drag a sqlite database and WAL files into it and then using a timeline slider see all the states of the database over time? :)

We're using SQLite in production very heavily with millions of databases and fairly high operations throughput.

But we did run into some scariness around trying to use Litestream that put me off it for the time being. Litestream is really cool but it is also very much a cool hack and the risk of database corruption issues feels very real.

The scariness I ran into was related to this issue https://github.com/benbjohnson/litestream/issues/510

Litestream is a library that allows you to easily create backups. You can probably just do analytic queries on the backup data and reduce load on your server.

https://litestream.io/

One possible strategy is to have one directory/file per customer which is one SQLite file. But then as the user logs in, you have to look up first what database they should be connected to.

OR somehow derive it from the user ID/username. Keeping all the customer databases in a single directory/disk and then constantly "lite streaming" to S3.

Because each user is isolated, they'll be writing to their own database. But migrations would be a pain. They will have to be rolled out to each database separately.

One upside is, you can give users the ability to take their data with them, any time. It is just a single file.

[0]. https://litestream.io/

Upstream Kuma uses a local SQLite database to store account data, configuration for services to monitor, notification settings, and more. To make sure that our data is available across redeploys, we will bundle Uptime Kuma with Litestream, a project that implements streaming replication for SQLite databases to a remote object storage provider. Effectively, this allows us to treat the local SQLite database as if it were securely stored in a remote database.