The discussion revolves around installing Discourse v1.7.2 using Docker. Kel is trying to install an older version of Discourse due to a script compatibility issue. pfaffman suggests modifying the app.yml file with the desired version number, but Kel notes that this file is created after the initial installation.
fefrei provides a solution to create app.yml manually and downgrade, but warns that this will result in complete data loss. Since Kel is willing to lose the data, this solution works for them.
Additionally, pfaffman shares an alternative method to achieve this by copying the standalone.yml template and editing it, or using ./discourse-setup and interrupting the process to make changes. Kel confirms that these solutions are effective and is rebuilding their Discourse installation with the desired version.
Hi there,
First post so hello 
I am trying to install Discourse on a Digital Ocean Droplet all goes well, except I need to run a script that only works with v1.7.2 (long story just trust me!)
Tried everything I can think of to get Docker to do a clean install of v1.7.2 - does anyone know the correct procedure please?
Any help would be very much appreciated.
Kind regards
Kel
In app.yml where it says “tests-passed” you can put the the Git ID of the version you want.
So I think you want
version: 839a5e6e427bdffb87596f8fbe51c37796e40da3
version is in the file, but commented out.
Thanks!
I searched and found that solution earlier (it works using ‘v1.7.2’) but it seems to be only be able to do that as a rebuild the .yml file doesn’t exist until after the newest version has been installed.
These are the instructions I followed:
discourse/docs/INSTALL-cloud.md at main · discourse/discourse · GitHub
I need to be able to change the version number between the install and the setup.
All I have managed to do so far is install and then downgrade, that’s not what I am looking for.
The reason for this is that there seems to be some kind of database incompatibility with the script I am trying to run and the rebuild doesn’t fix it - although this is a guess!
I feel like I am missing something obvious.
You can create app.yml manually (there is a template in /var/discourse/samples/standalone.yml) – but if you already bootstrapped and want to downgrade, this is easy as long as you are willing to lose your data. Simply update app.yml, then run this:
cd /var/discourse/
./launcher stop app
rm -rf shared/standalone/ # wipe shared volume
./launcher rebuild app
Executing these commands will completely reset Discourse! All content, users and settings will be deleted.
I defintiely want to lose the data, everything needs to go so it’s a complete fresh install…
This is probably what I was missing - thank you!!!
I’d done everything but this one line!!!
Thank you!!!
You can cp samples/standalone.yml containers and edit it by hand, or use ./discourse-setup and hit a control C after it’s through configuring. There’s an undocumented 5 second pause before it starts the build, for just that purpose.
Brillaint, this is the magic dust I was looking for and couldn’t find 
I am already rebuilding and know it’s working as I’ve seen all the database commands run again - so have a lot of confidence I am going to end up with a 1.7.2 and corresponding database!
We will see, I will let you know!
Thanks again