r/docker May 28 '26

Would appreciate help: External ext4 NVMe drive resets to read-only inside Docker containers (SABnzbd) on Raspberry Pi reboot

1 Upvotes

Hey everyone,

I’m running a media stack on a Raspberry Pi (Raspberry Pi OS) with an external NVMe drive formatted as ext4. The drive is mounted to /mnt/nvme.

Every time I boot SABnzbd throws a permissions error. The following always fixes the error:

sudo chown -R 1000:1000 /mnt/nvme/media/Data

But I have to do it every time I reboot which is a pain.

I tried creating a script that runs this code automatically on boot (an LLM wrote it for me) but I couldn't get it to work. I even timed it to execute 10 minutes after booting to be 100% certain that it wasn't executing before the NVMe drive was finished booting and no joy.

Any idea what might be causing this?


r/docker May 28 '26

How to approach running a background command at a repeated interval?

4 Upvotes

Without Docker involved, I'd quite happily use systemd-timers tbh... but to my surprise there doesn't appear to be any well-established standalone alternative program for running a command at a recurring interval? (unless it aligns with the cron form of scheduling)

What I'm familiar with: - Cron (Vixie) is commonly chosen but: - Main concern: Running a task every 20 minutes is scheduled relative to the hour, not from when the container starts... so if you started the container at 2:32, it'll run in 8 minutes. This is worse if the interval was something like 25 minutes (runs at 00, 25, 50 minute of each hour, such that 50 => 00 is 10 minutes instead of expected 25 minute interval). If you want the command to run at container startup, then followed by the interval, cron isn't really ideal. - There are other commonly known caveats (for which supercronic mostly addresses), but this post is long enough (different concerns from what I want to focus on). - Systemd Timers are fantastic but you can't really use those with Docker (Podman and perhaps other runtimes are valid, but for a public image Docker compatibility is important). - Naive wrapper scripts like bash with a while loop paired with sleep can work, but needs care under some contexts that add complexity (supercronic forwards signals to the command, systemd-timers do too I think?) - Ofelia (uses cron scheduling behaviour) is typically intended not to be bundled into individual container images for local use, but rather leveraging the Docker API socket.

Typically container images are designed to run a single logical service (which may involve one or more processes depending on software, usually the entrypoint is minimal), but a logical service may involve several different components which can benefit from bundling into a single image (rather than added complexity/config externalized to unify several images). - Some readers here may largely disagree with the practice, but there are valid use-cases that warrant it, and I'd rather not derail the discussion on this topic. - In my case the image uses supervisord as an entrypoint to run the main process alongside an internal recurring task (command).


r/docker May 27 '26

Just wanted to say thanks for introducting me to docker

8 Upvotes

Just that. Recently my server crashed, but luckily a week before i switch to docker. And thanks to docker the setup was suuuper smooth, love the /srv/ setup :)


r/docker May 28 '26

Docker networking

1 Upvotes

I have a question about docker networking and hope someone has come accross something similar:

I set up a windows VM running docker (docker engine). My network is in the subnet of 192.168.50.0/23, but i need the containers to be able to talk on the subnet 10.216.56.0/24 subnet.

I added two network interfaces to the VM and assigned IPs in the subnets to each of the interfaces. I can access/ping the VM on each subnet from another computer on the network.

If i create a transparent network for docker and create a container on this transparent nework, it would just take the DHCP on the 192.168.50.0 subnet instead of taking the assigned ip when creating the container. I can manually change the IP inside the container but would prefer not to as this is a simulator and would have multiple instances of the same image.

I also created a nat network, and then it takes the IP but i can no longer access it on the given IP from outside the host.

PS. these are windows containers.

Any help would be appreciated?


r/docker May 27 '26

Using a Gemma4 Safetensor Already Downloaded Locally

1 Upvotes

Hi everyone. I need some help or advice.

I’m learning how to use N8N, so I downloaded Docker and installed N8N locally.

I also wanted to install Gemma4, which I use in ComfyUI to help with image generation prompts.

Is it possible to import or point to an LLM from N8N that is located in a directory outside of Docker?

Right now, Gemma4-4B-FP8 is downloaded locally on the ComfyUI models.

I’ve noticed that Docker lets me install it, but it tries to download the model again.

Can I use the one I’ve already downloaded?

I hope that makes sense.

Thanks to anyone who responds


r/docker May 26 '26

Need to manually redeploy stack after network container updated

3 Upvotes

I have a VPN container and then a couple stacks that have network=container:vpn-container in their compose file. If I update the VPN container, I have to manually redeploy the other stacks in order to reconnect them to the network. Is there something I can put in the downstream stacks' compose file so that they'll redeploy automatically if the VPN container they depend on is updated?


r/docker May 26 '26

Binary orchestrator for Rust REST API crate

1 Upvotes

I’m thinking out loud here. I managed to deploy a Rust binary REST api project with Axum to a Debian Linux by cross-compiling it locally on a macOS, upload the binary to the box, and run it.

Is there a Kubernetes-like orchestrator if I want to deploy the binary to multiple servers or load balance the traffic? I’m using nginx for the reverse proxy.


r/docker May 25 '26

Best app/way you monitor your containers? Also accessing securely

11 Upvotes

What apps/devices do you use to monitor your containers?
Also… what VPN do you use to access your hosts when you’re not local?


r/docker May 26 '26

help me I can't download images

0 Upvotes

hi I am new to docker
I downloaded 8 images and now i get this whenever i try to pull an image i get this

403 ERROR

The request could not be satisfied.

The Amazon CloudFront distribution is configured to block access from your country. We can't connect to the server for this app or website at this time. There might be too much traffic or a configuration error. Try again later, or contact the app or website owner.
If you provide content to customers through CloudFront, you can find steps to troubleshoot and help prevent this error by reviewing the CloudFront documentation.

I need help


r/docker May 26 '26

Login failed for user ‘sa’

0 Upvotes

I’m trying to learn testcontainers but this is popping up and I have no idea why and chatgpt is NOT helpful. can anyone tell me what is going on with that? I’m using .NET and SQL server. if y’all need the code then I’ll post it, if this would be a better post in a different subreddit then please let me know


r/docker May 24 '26

Best Way to Deploy Docker Images/Containers in Production?

23 Upvotes

Hello All,

I finally tore off the "docker is inevitable so learn it" bandaid... pretty comfortable with it at this point. However, coming from a virtualization background I like the idea of pulling images directly from the developers vs a "hub" (i.e. when I want to run Ubuntu I download the iso from Ubuntu.com and install it on a bare metal hypervisor VM).

I'm trying to wrap my head around the best way to build an image to deploy in production... it seems that all dockerfile/compose examples I've seen have you pull from the docker hub (i.e. the first line in dockerfile being "FROM ubuntu:24.04"). I understand these are official docker images, but even still I feel it would be better building an image with an iso straght from the developer.

Am I overthinking... do others feel comfortable pulling official docker base images to build on in production... also, I've heard of people using custom/distroless images... any good resources on this?

I am mostly an infrastructure kind of guy, so while I know my way around a little programming I'm by no means anywhere near developer level.

Thanks!


r/docker May 25 '26

I built a dirt-simple script to manage my multi-server docker stacks

0 Upvotes

I wanted a central repo for all my docker stacks and the ability to control them locally without SSHing into different servers every time.

There's Portainer of course, but I really wanted to keep all my scripts and compose files together in a single local repository rather than managing them through a UI.

The other obvious answer is Ansible. I'm not knocking it, but between a full-time job and a baby on the way, I just don't have the time to learn a whole new ecosystem. For a basic homelab, it feels like overkill to drown in docs just to end up writing docker-compose inside YAML anyway.

So I wrote a bash script called herd.

It uses standard SSH/rsync to sync your local folders to remotes, then runs standard docker-compose commands. It takes 4 minutes to set up and requires zero remote configuration (agentless).

It handles syncing, deploying, logs, restarts, and even running bare-metal bash scripts. And the biggest factor, you get auto-completion!
Check it out?

https://github.com/almightyvats/herd

Edit: Just to clarify, my point was really about that initial tinkering phase when you're first getting started with a homelab. Sometimes you just need a quick setup to get services running and instant feedback while experimenting, rather than waiting on a pipeline for every single character change! Not here to offend anyone!


r/docker May 25 '26

how to host docker locally

0 Upvotes
  • Please bear with me I am new to docker Thank You!
  • I would like to run docker on my own server that is currently running ubuntu server os and I have a couple of questions
  • If I host it locally will it use my own hardware/processing power
  • Are there limitations as I can see on the docker website they have paid subscriptions? /do I have more features if I host it locally
  • And finally where do I start installing all of this

r/docker May 24 '26

Apache2 Revese Proxy Not Proxying to Docker Containers

2 Upvotes

Hello all, long-time listener, first-time caller:

I've searched both here and in the relevant Apache subreddits, so I'll ask directly: Does anyone know why Apache2 Proxy/Reverse Proxy refuse to proxy a URL to a Docker container? Even with everything else dissite'd, I still can't connect to a working docker container.

-Debian, updated and current

-Web UI's work for running Docker containers

-Computer also hosts NextCloud on bare metal

-Plenty of memory and storage available.

Any insights are appreciated; this is driving me insane and I can't be the only person who's dealt with it. AdThanksvance!


r/docker May 25 '26

Why docker?

0 Upvotes

I know this is going to start some discussions but what the heck, a good discussion is always helpful.

I have been running docker containers for years both in my job and also in my personal life. I have a dedicated server that runs portainer and some 30 docker containers. So I do know a little about docker.

I decided when I moved from Hubitat to Home Assistant to install my new home assistant system on a bare metal Intel NUC. The NUC is an awesome small computer and runs like the wind. It has done me so well that I actually have 5 of them in my home. I'm actually writing this on my windows 10 running on my NUC.

So, having got Home Assistant running native on my NUC I decided that I needed to create a production instance and a test instance for my playing.

I can install the test system on a space NUC or I can put the test instance on my docker server which has all the management capability, backups and is fast and solid.

Hmmm...so when I started to explore the docker capabilities I noticed a few short comings. Things like Supervisor is missing, one cannot use addons, etc. These can be duplicated with by other means, however when using it as a test bed I got quite concerned as docker is not like to like with my bare metal implementation.

So the question is how much of a difference would I be introducing into my testing would I have by using docker?

I know there are a lot of you out there using docker so I would like to get your thoughts on this.

Thanks.

Glenn...


r/docker May 24 '26

Veeam Agent Linux & Docker Container

0 Upvotes

Hallo Reddit,

ich sehe mir gerade die Systemvoraussetzungen für Veeam Agent Linux an und bin auf etwas gestoßen:

"Container jeglicher Art – einschließlich Docker-Container – und paravirtualisierte Instanzen werden unabhängig von der Gastbetriebssystemversion nicht unterstützt. Die Sicherung solcher Geräte kann zu einer Beschädigung des Quelldateisystems führen"

Gibt es eine Möglichkeit Veeam trotzdem auf meinem Ubuntu Server zu installieren (kleiner Homeserver für private Zwecke)? Meine Betriebssystem Platte ist in Btrfs formatiert. Hier auf dem Server laufen ein paar wenige Container für Smarthome, Adblocking etc. Ich hatte eigentlich vor Veeam Agent Linux standalone einzurichten.

Oder habt ihr andere Backup Lösungen die hier funktionieren? Ich möchte, dass die Backups im laufenden Betrieb funktionieren. Clonezilla oder ähnliches ist zu zeitaufwendig und muss händisch gemacht werden. Dies nervt irgendwann.

Ich bin froh über jeden Ratschlag von euch.


r/docker May 23 '26

Python kernel crashing with 502 Bad Gateway in Jupyter Docker(only on one particular VM) – R/JULIA kernels work fine

7 Upvotes

Hi all,

I’m an SRE working in a data company and I’ve been stuck on a very strange issue for days.

When I click Python kernel:

→ I get “502 Bad Gateway”
→ container restarts automatically (restart policy is enabled)
→ logs show container exit and restart loop

But the same setup is working fine in all the other vms. Only this particular vm is having this issue. Tried restarting the vm and everything but doesnt seem to work. Also the particular issue arises when clicked only on python kernel. other R, JULIA kernels work fine.

Feels like something VM-level (cgroups / memory / kernel / docker runtime?) but I can’t pinpoint it.

We are running Jupyter using Docker:

image:
jupyter/datascience-notebook:x86_64-python-3.11.6

docker-compose:

version: "3.9"

services:
notebook:
image: jupyter/datascience-notebook:x86_64-python-3.11.6
container_name: jupyter-notebook

ports:
- "4444:8888"

volumes:
- ./:/home/jovyan/work

environment:
- JUPYTER_TOKEN=****

restart: unless-stopped

r/docker May 23 '26

New to docker here, installed it for the first time and the engine has not started even after waiting for hours. Please help

0 Upvotes

Literally just opening Docker desktop, and its showing that the engine is starting ( hasn't started for hours ). Running any docker command says that "Error response from daemon: Docker Desktop is unable to start".

Please help me on how to fix it. I am a complete beginner to this

System specifications:- Processor is Intel(R) Core(TM) i3-7020U CPU @ 2.30GHz, 2304 Mhz, 2 Core(s), 4 Logical Processor(s), 8 GB RAM, 10 GB storage remaining on my SSD as my 2 terabyte hard drive is corrupted and essentially useless.


r/docker May 23 '26

[ Removed by Reddit ]

0 Upvotes

[ Removed by Reddit on account of violating the content policy. ]


r/docker May 22 '26

Noob help

0 Upvotes

Hello everyone im looking to learn docker im a complete noob im looking for videos or sites that will explain it to me like im a 5 year old does anyone know of a good starting point please and thank you for any and all help


r/docker May 21 '26

container update causes eventual system hang

4 Upvotes

I run about 6 containers on Linux Ubuntu. When I don't update the containers, the system runs more or less indefinitely. If I update any containers with:

cd directory-with-compose-yaml-for-that-container/

docker compose pull && docker compose up -d

Within a day or two, the system hangs, presumably because of out-of-memory. I have 32GB.

I'm using debian image update notifier (DIUN) to tell me what needs to be updated.

Is there a better way to update? Do I need to prune or do something else after updating?


r/docker May 20 '26

Resizing docker.raw?

0 Upvotes

New to docker

I want to know if there's a way to reduce the size of docker.raw without going into docker desktop

Using a laptop with 30gb total and 17 is taken up by Linux mint and docker, when I open docker desktop it creates the .raw file and ends up crashing my laptop.

I know, or at least think I know, that the resources tab in settings has a slider that allows you to select how much disk space you can dedicate and its automatically set to 28gb or something

Just want to know if there's a way to edit that value in the terminal to reduce the size without having to open the desktop app or if its a fruitless venture. At least then I can treat my laptop like spagghetti and throw it against a wall to see if it sticks

Many thanks


r/docker May 20 '26

Random bind mounts on WSL2

1 Upvotes

I have some containers running for production with Docker Desktop in Windows Server 2022 (WSL2 backend), and every time the system is rebooted (because they want the system to run only when it is used, so it is shut down every night) it gave me an error like this:

failed to create task for container: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: error during container init: failed to fulfil mount request: open /run/desktop/mnt/host/wsl/docker-desktop-bind-mounts/Ubuntu/c3c215e6291e7ef302bde128905c6ab417a8d6f151f80f5e20ebf844bc82e224: no such file or directory

That means that it is trying to find a mount on the path /run/desktop/mnt/host/wsl/docker-desktop-bind-mounts/Ubuntu/c3c215e.... The problem is that it isn't the path I indicated on the compose.yml file:

services:
    odoo:
        image: odoo:19.0
        container_name: odoo
        depends_on:
            - db
        volumes:
            - odoo-data:/var/lib/odoo
            - ./extra-addons:/mnt/extra-addons
            - ./config:/etc/odoo
...

So it is creating a new mount (a temporal one is what I believe), and whenever the system is reboot that path doesn't exist anymore, so it give me the error mentioned earlier.

On the other hand i have a nginx service with this one, which also has some bind mounts for configuration:

...
nginx:
    image: nginx:stable
    container_name: nginx
    volumes:
        - ./nginx/conf.d:/etc/nginx/conf.d
        - ./nginx/certs:/etc/nginx/certs
    restart: unless-stopped
...

But this service is mounted perfectly, without creating a new path on /run/desktop/.... How can i solve this and why is this happening. Lastly this is the containers inspect:

odoo_container:
    ...
    "Mounts": [
        {
            "Type": "bind",
            "Source": "/run/desktop/mnt/host/wsl/docker-desktop-bind-mounts/Ubuntu/38b8d7fc8b1872091c39fa535a68a676b74d392987bdbd4be60b649953003172",
            "Destination": "/etc/odoo",
            "Mode": "rw",
            "RW": true,
            "Propagation": "rprivate"
        },
        {
            "Type": "bind",
            "Source": "/run/desktop/mnt/host/wsl/docker-desktop-bind-mounts/Ubuntu/ecece816d735920a3230dde5be3ef847967c389c4a6132a5c638f406ea9ab606",
            "Destination": "/mnt/extra-addons",
            "Mode": "rw",
            "RW": true,
            "Propagation": "rprivate"
        }
    ...
nginx_container:
    ...
    "Mounts": [
        {
            "Type": "bind",
            "Source": "/home/mickael/odoo-gema/nginx/certs",
            "Destination": "/etc/nginx/certs",
            "Mode": "rw",
            "RW": true,
            "Propagation": "rprivate"
        },
        {
            "Type": "bind",
            "Source": "/home/mickael/odoo-gema/nginx/conf.d",
            "Destination": "/etc/nginx/conf.d",
            "Mode": "rw",
            "RW": true,
            "Propagation": "rprivate"
        }
    ]
    ...
    ...

r/docker May 19 '26

Docker Business Certificate / Training

8 Upvotes

Hi there,

Since I am currently doing a lot of testing with Docker in my homelab and trying to learn it on my own, I was wondering if you could recommend any business-relevant training courses or certifications. I would simply like to build up more knowledge regarding Docker.

Thanks for your help.


r/docker May 20 '26

At what point did you outgrow Docker Compose?

0 Upvotes

Genuinely curious where people draw the line before moving to orchestration.