docs: upgrade from 2.2.x

docs/upgrading.md

@@ -1,21 +1,58 @@
 # How To Upgrade bbb-docker
 
-## Backup
+### within `2.3.x
+#### Backup
 if you use greenlight, create a database backup first
 ```bash
 docker exec -t docker_postgres_1 pg_dumpall -c -U postgres > /root/greenlight_`date +%d-%m-%Y"_"%H_%M_%S`.sql
 ```
 
-## Upgrading
+#### Upgrading
 ```bash
 # upgrade!
 ./scripts/upgrade
 
 # restart updated services
-./scripts/compose up -d
+docker-compose up -d
 ```
 
 
-## "no such file or directory: ./scripts/upgrade"
-If you're on an old version, you might get this error. 
-A simple `$ git pull` resolves that, by fetching a newer version which includes the upgrade script.
+### from `2.2.x` to `2.3.x`
+
+```bash
+cd bbb-docker
+
+# if you use greenlight: create a database backup
+./scripts/compose exec postgres pg_dumpall -c -U postgres > /root/bbb-docker-2.2-backup.sql
+
+# stop bbb-docker
+./scripts/compose down
+
+# go back and rename folder
+cd ..
+mv bbb-docker bbb-docker-2.2-archived
+
+# get bbb-docker 2.3
+git clone --recurse-submodules https://github.com/bigbluebutton/docker.git bbb-docker
+cd bbb-docker
+
+# do setup
+./scripts/setup
+
+# optionally do additional changes
+nano .env
+
+# regenerate the docker-compose file
+./scripts/generate-compose
+
+# if you use greenlight, import database backup
+docker-compose up -d postgres
+cat /root/bbb-docker-2.2-backup.sql | docker-compose exec -T postgres psql -U postgres
+
+# start new BBB 2.3
+docker-compose up -d
+
+
+```
+- `$ cd bbb-docker`
+- (if you use greenlight) create a database backup first