prudkohliad

How to deploy a Next.js app to a Hetzner VPS using SST and Docker

“SST is a framework that makes it easy to build modern full-stack applications on your own infrastructure. SST v3 uses Pulumi and Terraform.” – SST Documenation

In this guide we will be deploying a Next.js app on a Hetzner VPS using SST and Docker. This guide is a follow-up on my previous post. If you find something that does not make sense here, there’s a good chance you’ll find the answers there – How to deploy a Next.js app to a VPS on Hetzner using Docker and GitHub Actions.

TL;DR: See this GitHub Gist for the full sst.config.ts file.

Add SST to the project

To add SST to the project, run the following command:

pnpx sst@ion init

This will show an interactive prompt. Select “Yes” and then “aws”:

SST init output – Terminal

Make sure all the necessary packages are installed:

pnpm install

This will create the sst.config.ts file where we will be adding all the configuration.

Also, some other files/directories will be created. Let’s add them to .dockerignore, we don’t want them to end up the the Docker image:

# sst
.sst
sst.config.ts
tsconfig.json

This is what the sst config file looks like currently:

/// <reference path="./.sst/platform/config.d.ts" />

export default $config({
  app(input) {
    return {
      name: "next-self-hosted",
      removal: input?.stage === "production" ? "retain" : "remove",
      home: "aws",
    };
  },
  async run() {},
});

We are not going to use AWS, so let’s set the home parameter to "local": 

/// <reference path="./.sst/platform/config.d.ts" />

export default $config({
  app(input) {
    return {
      name: "next-self-hosted",
      removal: input?.stage === "production" ? "retain" : "remove",
      home: "local",
    };
  },
  async run() {},
});

Now can start adding things to the run() function.

Create an API Token on Hetzner

In order to create a VPS on Hetzner using SST, we are going to need a Hetzner API Token. Let’s generate a new one.

Open the project in Hetzner console, navigate to the “Security” tab:

Project Security settings – Hetzner Cloud UI
Project Security settings – Hetzner Cloud UI

Generate an API token:

Generating an API token – Hetzner Cloud UI
Generating an API token – Hetzner Cloud UI

A new token will be added to you project:

The API token – Hetzner Cloud UI
The API token – Hetzner Cloud UI

The token will only be shown once, make sure to not lose it.

Add TLS and Hetzner Providers:

pnpm sst add tls
pnpm sst add hcloud
pnpm install

Generate an SSH key

In order to execute further commands after we create a Hetzner VPS, we need to make sure that an SSH key is added to it during the creation. To do that, we will create an SSH token locally and then add it’s public part to Hetzner. Add the following code to the run function:

// In the run() function:

// Generate an SSH key
const sshKeyLocal = new tls.PrivateKey("SSH Key - Local", {
  algorithm: "ED25519",
});

// Add the SSH key to Hetzner
const sshKeyHetzner = new hcloud.SshKey("SSH Key - Hetzner", {
  publicKey: sshKeyLocal.publicKeyOpenssh,
});

Deploy the app:

pnpm sst deploy

SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Created     SSH Key - Local tls:index:PrivateKey
|  Created     SSH Key - Hetzner hcloud:index:SshKey

✓  Complete

You will see that a new SSH key has been added to Hetzner:

The SSH key – Hetzner Cloud UI
The SSH key – Hetzner Cloud UI

Now we can proceed with creating a VPS.

Create a Server

The following command will ensure that a new VPS is created in your project:

// In the run() function:

// Create a Server on Hetzner
const server = new hcloud.Server("Server", {
  image: "docker-ce",
  serverType: "cx22",
  location: "nbg1",
  sshKeys: [sshKeyHetzner.id],
});

Here I am using docker-ce image, because it comes with Docker already installed. You can use Hetzner Cloud API to list all the available images, server types and datacenters.

Verify that the server gets created correctly:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Created     Server hcloud:index:Server (34.5s)

✓  Complete

You should also be able to see the newly created server in the console:

The Server – Hetzner Cloud UI
The Server – Hetzner Cloud UI

Connect to Docker Server on the VPS

In order to build the app Docker image on the VPS and be able to create networks, volumes and containers, we need to make a bridge between our local machine and Docker Server on the VPS. To do that, we are going to need the Docker provider:

pnpm sst add docker
pnpm install

Store the private SSH key on disk so that the SSH client can access it. Сreate a connection to the Docker server on the VPS:

// At the top of the file:
import { resolve as pathResolve } from "node:path";
import { writeFileSync as fsWriteFileSync } from "node:fs";

// In the run() function:

// Store the private SSH Key on disk to be able to pass it to the Docker
// Provider
const sshKeyLocalPath = sshKeyLocal.privateKeyOpenssh.apply((k) => {
  const path = "id_ed25519_hetzner";
  fsWriteFileSync(path, k, { mode: 0o600 });
  return pathResolve(path);
});

// Connect to the Docker Server on the Hetzner Server
const dockerServerHetzner = new docker.Provider("Docker Server - Hetzner", {
  host: $interpolate`ssh://root@${server.ipv4Address}`,
  sshOpts: ["-i", sshKeyLocalPath, "-o", "StrictHostKeyChecking=no"],
});

Make sure to also add the private SSH key id_ed25519_hetzner to .gitignore and .dockerignore, so that it does not make it into your GitHub repo and to the Docker image.

Trigger the deployment to verify the changes:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Created     Docker Server - Hetzner pulumi:providers:docker

✓  Complete

Build the Docker image

Now we can build the Docker image on the remove Docker server:

// In the run() function:

// Build the Docker image
const dockerImageHetzner = new docker.Image(
  "Docker Image - App - Hetzner",
  {
    imageName: "next-self-hosted/next-self-hosted:latest",
    build: {
      context: pathResolve("./"),
      dockerfile: pathResolve("./Dockerfile"),
      target: "production",
      platform: "linux/amd64",
    },
    skipPush: true,
  },
  {
    provider: dockerServerHetzner,
    dependsOn: [server],
  }
);

Let’s trigger the deployment to see if everything works:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Log         Starting Docker build
< ... A PRETTY LONG BUILD LOG HERE ... >
|  Log         Image built successfully, local id "sha256:629a6cdfc298c74599a3056278e31c64197a87f6d11aab09573bc9171d2f3362"
|  Created     Docker Image - App - Hetzner docker:index:Image (36.0s)

✓  Complete

Now, let’s check that Docker image made it to the server:

ssh [email protected] -i ./id_ed25519_hetzner -o StrictHostKeyChecking=no -C "docker image ls"
REPOSITORY                          TAG       IMAGE ID       CREATED              SIZE
next-self-hosted/next-self-hosted   latest    629a6cdfc298   About a minute ago   712MB

Awesome!

Docker networks

We will create two networks: Public and Internal. The Public network is for services to which NGINX is connected, i.e. for services that have to be exposed to the outside (e.g. the Next.js application or an API server). The Internal network is for services that are not meant to be exposed to the outside e.g. Postgres database, Redis cache:

// In the run() function:

// Setup Docker Networks
const dockerNetworkPublic = new docker.Network(
  "Docker Network - Public",
  { name: "app_network_public" },
  { provider: dockerServerHetzner, dependsOn: [server] }
);
const dockerNetworkInternal = new docker.Network(
  "Docker Network - Internal",
  { name: "app_network_internal" },
  { provider: dockerServerHetzner, dependsOn: [server] }
);

Trigger the deployment:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Created     Docker Network - Public docker:index:Network (2.3s)
|  Created     Docker Network - Internal docker:index:Network (3.1s)

✓  Complete

Check that networks app_network_internal and app_network_public are present on the remote:

ssh [email protected] -i ./id_ed25519_hetzner -o StrictHostKeyChecking=no -C "docker network ls"
NETWORK ID     NAME                   DRIVER    SCOPE
0590360bd4ae   app_network_internal   bridge    local
e3bd8be72506   app_network_public     bridge    local
827fa5ca5de2   bridge                 bridge    local
dc8880514199   host                   host      local
f1481867db18   none                   null      local

Docker volumes

We will create a volume to store the application build files (the .next folder):

// In the run() function:

// Setup Docker Volumes
const dockerVolumeAppBuild = new docker.Volume(
  "Docker Volume - App Build",
  { name: "app_volume_build" },
  { provider: dockerServerHetzner, dependsOn: [server] }
);

Deploy and verify that the docker volume app_volume_build is present on the VPS:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Created     Docker Volume - App Build docker:index:Volume

✓  Complete

ssh [email protected] -i ./id_ed25519_hetzner -o StrictHostKeyChecking=no -C "docker volume ls"
DRIVER    VOLUME NAME
local     app_volume_build

The Build container

We are going to run a one-off container (a.k.a. Init Container) to build the Next.js application and store the result in the .next folder, that will be shared with the main application container through the volume that we have created above:

// In the run() function:

// Run a one-off container to build the app
const dockerAppBuildContainer = new docker.Container(
  "Docker Container - App Build",
  {
    name: "app_container_build",
    image: dockerImageHetzner.imageName,
    volumes: [
      {
        volumeName: dockerVolumeAppBuild.name,
        containerPath: "/app/.next",
      },
    ],
    command: ["pnpm", "build"],
    mustRun: true,
  },
  {
    provider: dockerServerHetzner,
  }
);

Deploy and verify via logs that the build has been successful:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Created     Docker Container - App Build docker:index:Container (1.1s)

✓  Complete

ssh [email protected] -i ./id_ed25519_hetzner -o StrictHostKeyChecking=no -C "docker logs -f app_container_build"

> next-self-hosted@ build /app
> next build

  ▲ Next.js 14.2.5

   Creating an optimized production build ...
 ✓ Compiled successfully
   Linting and checking validity of types ...
   Collecting page data ...
   Generating static pages (0/4) ...
   Generating static pages (1/4)
   Generating static pages (2/4)
   Generating static pages (3/4)
 ✓ Generating static pages (4/4)
   Finalizing page optimization ...
   Collecting build traces ...

Route (app)                              Size     First Load JS
┌ ○ /                                    142 B          87.2 kB
└ ○ /_not-found                          871 B          87.9 kB
+ First Load JS shared by all            87 kB
  ├ chunks/52d5e6ad-40eff88d15e66edb.js  53.6 kB
  ├ chunks/539-e1fa9689ed3badf0.js       31.5 kB
  └ other shared chunks (total)          1.84 kB


○  (Static)  prerendered as static content

The App container

Now we will add a “runner” container, that will use the build output from the Build container, and run next start:

// In the run() function:

const dockerAppContainer = new docker.Container(
  "Docker Container - App",
  {
    name: "app",
    image: dockerImageHetzner.imageName,
    volumes: [
      {
        volumeName: dockerVolumeAppBuild.name,
        containerPath: "/app/.next",
      },
    ],
    networksAdvanced: [
      { name: dockerNetworkPublic.id },
      { name: dockerNetworkInternal.id },
    ],
    command: ["pnpm", "start"],
    restart: "always",
  },
  { provider: dockerServerHetzner, dependsOn: [dockerAppBuildContainer] }
);

Deploy and verify that the app has started successfully:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Created     Docker Container - App docker:index:Container (1.1s)

✓  Complete

ssh [email protected] -i ./id_ed25519_hetzner -o StrictHostKeyChecking=no -C "docker logs -f app"

> next-self-hosted@ start /app
> next start

  ▲ Next.js 14.2.5
  - Local:        http://localhost:3000

 ✓ Starting...
 ✓ Ready in 497ms

The app container might fail, because the build container has not finished building yet, but it will soon recover and function normally.

Add Cloudflare certificates

In order to upload files to the VPS, we need to install the Command provider and the Polumi package:

pnpm sst add @pulumi/command
pnpm add -D @pulumi/pulumi
pnpm install

Make sure that the /root/app and /root/app/certs directories exist on the VPS and upload Cloudflare Origin Server certificates:

// At the top of the file
import { asset as pulumiAsset } from "@pulumi/pulumi";

// In the run() function:

// Make sure that app directory exists
new command.remote.Command("Command - Ensure app directory", {
  create: "mkdir -p /root/app",
  connection: {
    host: server.ipv4Address,
    user: "root",
    privateKey: sshKeyLocal.privateKeyOpenssh,
  },
});

// Make sure that app/certs directory exists
new command.remote.Command("Command - Ensure app/certs directory", {
  create: "mkdir -p /root/app/certs",
  connection: {
    host: server.ipv4Address,
    user: "root",
    privateKey: sshKeyLocal.privateKeyOpenssh,
  },
});

// Copy Certificates to the VPS
new command.remote.CopyToRemote(
  "Copy - Certificates - Key",
  {
    source: new pulumiAsset.FileAsset(
      pathResolve("./certs/cloudflare.key.pem")
    ),
    remotePath: "/root/app/certs/cloudflare.key.pem",
    connection: {
      host: server.ipv4Address,
      user: "root",
      privateKey: sshKeyLocal.privateKeyOpenssh,
    },
  }
);
new command.remote.CopyToRemote(
  "Copy - Certificates - Cert",
  {
    source: new pulumiAsset.FileAsset(
      pathResolve("./certs/cloudflare.cert.pem")
    ),
    remotePath: "/root/app/certs/cloudflare.cert.pem",
    connection: {
      host: server.ipv4Address,
      user: "root",
      privateKey: sshKeyLocal.privateKeyOpenssh,
    },
  }
);
new command.remote.CopyToRemote(
  "Copy - Certificates - Authenticated Origin Pull",
  {
    source: new pulumiAsset.FileAsset(
      pathResolve("./certs/authenticated_origin_pull_ca.pem")
    ),
    remotePath: "/root/app/certs/authenticated_origin_pull_ca.pem",
    connection: {
      host: server.ipv4Address,
      user: "root",
      privateKey: sshKeyLocal.privateKeyOpenssh,
    },
  }
);

Start Nginx

Copy Nginx configuration file to the VPS and start the Nginx container:

// In the run() function:

// Copy Nginx config to the VPS
const commandCopyNginxConfig = new command.remote.CopyToRemote(
  "Copy - Nginx Config",
  {
    source: new pulumiAsset.FileAsset(
      pathResolve("./nginx/production.conf")
    ),
    remotePath: "/root/app/nginx.conf",
    connection: {
      host: server.ipv4Address,
      user: "root",
      privateKey: sshKeyLocal.privateKeyOpenssh,
    },
  }
);

// Run the Nginx container
const dockerNginxContainer = new docker.Container(
  "Docker Container - Nginx",
  {
    name: "app_container_nginx",
    image: "nginx:1.27.0-bookworm",
    volumes: [
      {
        hostPath: "/root/app/nginx.conf",
        containerPath: "/etc/nginx/nginx.conf",
      },
      {
        hostPath: "/root/app/certs",
        containerPath: "/certs",
      },
    ],
    command: ["nginx", "-g", "daemon off;"],
    networksAdvanced: [{ name: dockerNetworkPublic.id }],
    restart: "always",
    ports: [
      {
        external: 443,
        internal: 443,
      },
    ],
    healthcheck: {
      tests: ["CMD", "service", "nginx", "status"],
      interval: "30s",
      timeout: "5s",
      retries: 5,
      startPeriod: "10s",
    },
  },
  { provider: dockerServerHetzner, dependsOn: [dockerAppContainer] }
);

return { ip: server.ipv4Address };

Deploy and verify that the Nginx container is running:

pnpm sst deploy
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Deploy

|  Deleted     Docker Container - App Build docker:index:Container
|  Created     Command - Ensure app/certs directory command:remote:Command
|  Created     Command - Ensure app directory command:remote:Command
|  Created     Docker Container - App Build docker:index:Container
|  Created     Copy - Certificates - Cert command:remote:CopyToRemote (1.2s)
|  Created     Copy - Nginx Config command:remote:CopyToRemote (1.2s)
|  Created     Copy - Certificates - Key command:remote:CopyToRemote (1.2s)
|  Created     Copy - Certificates - Authenticated Origin Pull command:remote:CopyToRemote (1.2s)
|  Deleted     Docker Container - App docker:index:Container
|  Created     Docker Container - App docker:index:Container (1.2s)
|  Created     Docker Container - Nginx docker:index:Container (7.1s)

✓  Complete
   ip: 116.203.183.180
   
ssh root@116.203.183.180 -i ./id_ed25519_hetzner -o StrictHostKeyChecking=no -C "docker ps -a"

CONTAINER ID   IMAGE                                      COMMAND                  CREATED         STATUS                     PORTS                          NAMES
9c2cb18db304   nginx:1.27.0-bookworm                      "/docker-entrypoint.…"   3 minutes ago   Up 3 minutes (healthy)     80/tcp, 0.0.0.0:443->443/tcp   app_container_nginx
32e6a4cee8bc   next-self-hosted/next-self-hosted:latest   "docker-entrypoint.s…"   4 minutes ago   Up 3 minutes               3000/tcp                       app
f0c50aa32493   next-self-hosted/next-self-hosted:latest   "docker-entrypoint.s…"   4 minutes ago   Exited (0) 3 minutes ago                                  app_container_build

As you can see, Nginx and the application are running smoothly.

The final check

It’s time to make sure that the DNS record is pointing to the right IP address (yes, it is possible to add this to the SST config too, via the Cloudflare provider):

DNS settings – Cloudflare UI
DNS settings – Cloudflare UI

Then, we can open the application and verify that it works:

The application in the browser
The application in the browser

Congratulations! We have now completed out SST dive and can enjoy the freshly deployed application 👌

Cleaning up

SST makes it very easy to clean up – just run pnpm sst remove and the whole setup will go away:

pnpm sst remove
SST ❍ ion 0.1.90  ready!

➜  App:        next-self-hosted
   Stage:      antonprudkohliad

~  Remove

|  Deleted     Docker Container - Nginx docker:index:Container (1.9s)
|  Deleted     Docker Container - App docker:index:Container
|  Deleted     Docker Container - App Build docker:index:Container
|  Deleted     Docker Image - App - Hetzner docker:index:Image
|  Deleted     Docker Volume - App Build docker:index:Volume (2.1s)
|  Deleted     Docker Network - Public docker:index:Network (3.1s)
|  Deleted     Docker Network - Internal docker:index:Network (3.2s)
|  Deleted     Copy - Nginx Config command:remote:CopyToRemote
|  Deleted     Docker Server - Hetzner pulumi:providers:docker
|  Deleted     Copy - Certificates - Authenticated Origin Pull command:remote:CopyToRemote
|  Deleted     Command - Ensure app/certs directory command:remote:Command
|  Deleted     Copy - Certificates - Key command:remote:CopyToRemote
|  Deleted     Command - Ensure app directory command:remote:Command
|  Deleted     Copy - Certificates - Cert command:remote:CopyToRemote
|  Deleted     Server hcloud:index:Server (16.8s)
|  Deleted     SSH Key - Hetzner hcloud:index:SshKey
|  Deleted     SSH Key - Local tls:index:PrivateKey

✓  Removed

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