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Updating.md

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+# Updating
+
+First of all, before you update, always read [the release notes of the NetBox Docker project](https://github.com/netbox-community/netbox-docker/releases).
+If a new version of NetBox is rolled our, be sure to also [check the release notes of NetBox itself](https://github.com/netbox-community/netbox/releases).
+
+When you followed [our Getting Started instructions](Getting-Started) instruction to get NetBox Docker running, then you should be able to follow this guide just fine.
+Otherwise you will have to figure out the analogous steps yourself.
+
+**IMPORTANT: Please make a backup of your data before updating!** [Our Troubleshooting page](Troubleshooting) has some information regarding this.
+
+## Update steps
+
+First, open a terminal and `cd` to your project folder.
+This is the folder where the `docker-compose.yml` file is.
+
+Now, stop all the containers that are running:
+
+```bash
+docker-compose down
+```
+
+Then, to update to the latest release, fetch all updates to the project files from the release channel:
+
+```bash
+git checkout release &&
+git pull -p origin release
+```
+
+_NOTE: If you instead want to update to a specific version, [see the respective guide](Version)._
+
+Now you need to tell Docker to fetch the latest NetBox Docker Container and also to fetch new version of the dependencies, such as a new Redis or PostgreSQL:
+
+```bash
+docker-compose pull
+```
+
+Now it's time to start all the containers again.
+This will also migrate the NetBox database schema automatically.
+
+```bash
+docker-compose up
+```
+
+Once NetBox has started, you should be ready to go.
+
+## Common Issues
+
+### Updating from below 1.x.x to 1.x.x
+
+Don't forget to update the `docker-compose.override.yml` file, [as described in the release notes](https://github.com/netbox-community/netbox-docker/releases/tag/1.0.0).
+
+### PostgreSQL Update
+
+Updates between major versions of PostgreSQL (e.g. version 11 to 12) require special attention.
+The easiest way to perform such an update is to backup the database on the old version and restore the data on the new version:
+
+**⚠️ IMPORTANT: Make sure to test this procedure first before applying it to valuable data ⚠️***
+
+```bash
+cd <path_to>/netbox-docker
+
+# Stop all containers
+docker-compose down
+
+# Only start the DB
+docker-compose up -d postgres
+docker-compose exec -T postgres sh -c 'pg_dump -cU $POSTGRES_USER $POSTGRES_DB' | gzip > db_dump.sql.gz
+
+# Stop the database and remove it's volme
+# THIS STEP WILL WIPE YOUR DATABASE!
+docker-compose rm -sfv postgres
+
+# Update NetBox Docker files and containers
+git checkout release && git pull -p origin release
+docker-compose pull
+
+# Restore the database
+docker-compose up -d postgres
+gunzip -c db_dump.sql.gz | docker-compose exec -T postgres sh -c 'psql -U $POSTGRES_USER $POSTGRES_DB'
+
+# Start all other containers
+docker-compose up
+```