How to Self-Host Nextcloud with Docker

What Is Nextcloud?

Nextcloud is a self-hosted cloud platform that replaces Dropbox, Google Drive, and Google Workspace. It provides file sync, sharing, calendar, contacts, office document editing, and a plugin ecosystem with hundreds of apps. Nextcloud is the most well-known self-hosted cloud solution, used by governments, universities, and millions of individuals. It is fully open source under the AGPL-3.0 license.

Prerequisites

A Linux server (Ubuntu 22.04+ recommended)
Docker and Docker Compose installed (guide)
2 GB of RAM minimum (4 GB recommended)
10 GB of free disk space for the application, plus storage for your files
A domain name (strongly recommended for remote access and mobile apps)

Docker Compose Configuration

Create a directory and docker-compose.yml:

mkdir -p ~/nextcloud && cd ~/nextcloud

services:
  db:
    image: postgres:17-alpine
    container_name: nextcloud-db
    restart: unless-stopped
    volumes:
      - nextcloud-db:/var/lib/postgresql/data
    environment:
      POSTGRES_DB: nextcloud
      POSTGRES_USER: nextcloud
      POSTGRES_PASSWORD: "change-this-db-password"
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U nextcloud"]
      interval: 10s
      timeout: 5s
      retries: 5

  redis:
    image: redis:7-alpine
    container_name: nextcloud-redis
    restart: unless-stopped

  app:
    image: nextcloud:32.0.6-apache
    container_name: nextcloud
    restart: unless-stopped
    ports:
      - "8080:80"
    volumes:
      - nextcloud-html:/var/www/html
    environment:
      # Database
      POSTGRES_HOST: db
      POSTGRES_DB: nextcloud
      POSTGRES_USER: nextcloud
      POSTGRES_PASSWORD: "change-this-db-password"  # Must match db service
      # Cache
      REDIS_HOST: redis
      # Admin account (first run only)
      NEXTCLOUD_ADMIN_USER: admin
      NEXTCLOUD_ADMIN_PASSWORD: "change-this-admin-password"
      # Access
      NEXTCLOUD_TRUSTED_DOMAINS: "localhost your-domain.com"
      # PHP tuning
      PHP_MEMORY_LIMIT: "512M"
      PHP_UPLOAD_LIMIT: "16G"
      APACHE_BODY_LIMIT: "0"  # No limit — let PHP handle it
    depends_on:
      db:
        condition: service_healthy
      redis:
        condition: service_started

  cron:
    image: nextcloud:32.0.6-apache
    container_name: nextcloud-cron
    restart: unless-stopped
    volumes:
      - nextcloud-html:/var/www/html
    entrypoint: /cron.sh
    depends_on:
      db:
        condition: service_healthy
      redis:
        condition: service_started

volumes:
  nextcloud-db:
  nextcloud-html:

Important: Replace all passwords with strong, unique values. The POSTGRES_PASSWORD must match in both the db and app services. Set NEXTCLOUD_TRUSTED_DOMAINS to your actual domain.

The cron service uses the same Nextcloud image and volume but runs background tasks (file scanning, notifications, cleanup) instead of the web server.

Start the stack:

docker compose up -d

The first startup takes 1-2 minutes while Nextcloud initializes the database and installs default apps.

Initial Setup

Open Nextcloud at http://your-server-ip:8080
If you set NEXTCLOUD_ADMIN_USER and NEXTCLOUD_ADMIN_PASSWORD, you’re logged in as admin automatically
If not, the web installer appears — create your admin account and select PostgreSQL as the database
Install recommended apps when prompted (Calendar, Contacts, Talk, etc.)

Configuration

Trusted Domains

If you access Nextcloud from a domain not in NEXTCLOUD_TRUSTED_DOMAINS, you’ll see “Access through untrusted domain.” Fix it:

docker compose exec -u www-data app php occ config:system:set trusted_domains 2 --value="new-domain.com"

Reverse Proxy Settings

When behind a reverse proxy (strongly recommended for HTTPS), configure Nextcloud to trust it:

docker compose exec -u www-data app php occ config:system:set overwriteprotocol --value="https"
docker compose exec -u www-data app php occ config:system:set trusted_proxies 0 --value="172.16.0.0/12"

Without overwriteprotocol, Nextcloud enters a redirect loop when accessed via HTTPS.

Email (SMTP)

Add SMTP environment variables for notifications and password resets:

environment:
  # ... existing vars ...
  SMTP_HOST: "smtp.gmail.com"
  SMTP_SECURE: "tls"
  SMTP_PORT: "587"
  SMTP_NAME: "[email protected]"
  SMTP_PASSWORD: "your-app-password"
  MAIL_FROM_ADDRESS: "nextcloud"
  MAIL_DOMAIN: "yourdomain.com"

Background Jobs

Verify the cron container is handling background tasks:

docker compose exec -u www-data app php occ background:cron

In the admin panel under Administration > Basic settings, confirm “Background jobs” is set to “Cron.”

External Storage

For large file libraries, mount external storage directly:

volumes:
  - nextcloud-html:/var/www/html
  - /mnt/storage/nextcloud-data:/var/www/html/data

Warning: Set this before first run. Moving data after installation requires occ maintenance:data-fingerprint and manual directory moves.

Advanced Configuration (Optional)

Office Document Editing

Install Collabora Online or OnlyOffice for real-time document editing:

docker compose exec -u www-data app php occ app:install richdocuments

Then deploy a Collabora container alongside Nextcloud and configure the WOPI URL in Settings > Office.

S3 Object Storage

For scalable storage with S3-compatible backends:

environment:
  OBJECTSTORE_S3_BUCKET: "nextcloud-data"
  OBJECTSTORE_S3_REGION: "us-east-1"
  OBJECTSTORE_S3_HOST: "s3.amazonaws.com"
  OBJECTSTORE_S3_KEY: "your-access-key"
  OBJECTSTORE_S3_SECRET: "your-secret-key"

Note: S3 storage replaces local file storage entirely. Configure before first run — migration is complex.

Performance Tuning

For larger installations (10+ users):

environment:
  PHP_MEMORY_LIMIT: "1G"
  PHP_UPLOAD_LIMIT: "16G"
  PHP_OPCACHE_MEMORY_CONSUMPTION: "256"

Reverse Proxy

With Nginx Proxy Manager:

Add a proxy host for cloud.yourdomain.com → http://nextcloud:80 (or your-server-ip:8080)
Enable SSL with Let’s Encrypt

In the Advanced tab, add:

client_max_body_size 16G;
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;

Configure Nextcloud’s trusted proxy and overwrite settings (see above)

See Reverse Proxy Setup for detailed instructions.

Backup

Back up both the application data and the database:

# Database backup (portable SQL dump)
docker compose exec nextcloud-db pg_dump -U nextcloud nextcloud > nextcloud-db-backup.sql

# Application data backup
docker compose stop
docker run --rm -v nextcloud-html:/data -v $(pwd):/backup alpine tar czf /backup/nextcloud-data-backup.tar.gz /data
docker compose start

The /var/www/html volume contains user files, configuration, and installed apps. The database contains user accounts, file metadata, sharing permissions, and calendar/contacts data. Both are critical. See Backup Strategy.

Troubleshooting

”Access through untrusted domain”

Symptom: Error page saying the domain is not trusted

Fix: Add the domain to trusted domains:

docker compose exec -u www-data app php occ config:system:set trusted_domains 2 --value="your-domain.com"

Redirect loop with HTTPS

Symptom: Browser shows “too many redirects” when accessing via HTTPS through a reverse proxy

Fix: Set the overwrite protocol:

docker compose exec -u www-data app php occ config:system:set overwriteprotocol --value="https"
docker compose exec -u www-data app php occ config:system:set trusted_proxies 0 --value="172.16.0.0/12"

Large file uploads failing

Symptom: Uploads fail for files larger than 512 MB

Fix: Increase limits in all layers:

Set PHP_UPLOAD_LIMIT: "16G" in the Nextcloud environment
Set APACHE_BODY_LIMIT: "0" to disable the Apache limit
If using a reverse proxy, set client_max_body_size 16G; in the proxy config
The effective limit is the smallest value across all layers

”PHP memory limit below recommended”

Symptom: Admin panel shows a warning about PHP memory

Fix: Set PHP_MEMORY_LIMIT: "512M" (or higher). Verify:

docker compose exec app php -i | grep memory_limit

Slow performance

Symptom: Page loads are slow, especially with many files

Fix:

Ensure Redis is running and connected (check admin panel > Overview)
Increase OPcache: PHP_OPCACHE_MEMORY_CONSUMPTION: "256"
Ensure cron is running (not AJAX-based background jobs)
Use PostgreSQL, not SQLite

Resource Requirements

RAM: 512 MB idle, 1-2 GB under active use with Redis and PostgreSQL
CPU: Low for file storage. Medium for document editing, video preview generation.
Disk: 1 GB for the application, plus all user file storage

Frequently Asked Questions

Is Nextcloud free?

Yes. Nextcloud is fully open source under AGPL-3.0. Nextcloud GmbH sells enterprise support, but the software is identical.

Can I run Nextcloud on a Raspberry Pi?

Yes, but performance is limited. A Pi 4 with 4 GB RAM and an SSD works for 1-3 users. For more users, use an Intel N100 mini PC.

Should I use PostgreSQL or MariaDB?

PostgreSQL is recommended for new installations. It handles concurrent access better. MariaDB also works well and has a larger community of Nextcloud users.

How does Nextcloud compare to Seafile?

Nextcloud is a full cloud platform (files, calendar, contacts, office, apps). Seafile focuses purely on file sync with better performance for large libraries. Use Nextcloud for an all-in-one platform. Use Seafile for fast file sync only.

Verdict

Nextcloud is the default recommendation for anyone wanting a self-hosted cloud platform. It replaces Dropbox, Google Drive, Google Calendar, Google Contacts, and more. The app ecosystem is massive, the community is the largest in self-hosting, and it’s backed by a company with a sustainable business model. The downside is complexity — Nextcloud has more moving parts than simpler alternatives, and performance tuning requires attention. For users who only need file sync, Syncthing or Seafile are lighter.