# Set Environmental Variables
**URL:** https://meta.discourse.org/t/set-environmental-variables/270832
**Category:** Self-Hosting
**Tags:** how-to
**Created:** [July 7, 2023, 12:02am UTC](https://meta.discourse.org/t/set-environmental-variables/270832 "2023-07-07T00:02:39Z")
**Posts on this page:** 14
**Page:** 1
### Author:  [@Discourse](https://meta.discourse.org/u/Discourse)
#### Post date: [July 7, 2023, 12:02am UTC](https://meta.discourse.org/t/set-environmental-variables/270832/1 "2023-07-07T00:02:39Z")
> š This is a #how-to guide for setting up environmental variables in a self-hosted Discourse installation.
>
> š Required user level: Administrator
Environmental variables play a crucial role in configuring your Discourse instance. They can store sensitive data like API keys and database passwords, making your installation more secure and flexible. In Discourse, environmental variables are set in the `app.yml` file within your Docker container setup.
Adding environmental variables to a `.yml` (YAML) file is straightforward. Hereās a basic example:
```plaintext
# This is a YAML file with environmental variables
env:
VARIABLE_NAME: "Variable Value"
ANOTHER_VARIABLE: "Another Value"
```
In the context of a Discourse Docker container, environmental variables are stored in the `env` section of your `app.yml` file.
> **Here's an example of an app.yml file:**
>
> ```yml
> ## this is the all-in-one, standalone Discourse Docker container template
> ##
> ## After making changes to this file, you must rebuild
> ## /var/discourse/launcher rebuild app
> ##
> templates:
> - "templates/postgres.template.yml"
> - "templates/redis.template.yml"
> - "templates/web.template.yml"
> - "templates/web.ratelimited.template.yml"
> ## Uncomment these two lines if you wish to add Lets Encrypt (https)
> #- "templates/web.ssl.template.yml"
> #- "templates/web.letsencrypt.ssl.template.yml"
>
> ## which TCP/IP ports should this container expose?
> ## If you want Discourse to share a port with another webserver like Apache or nginx,
> ## see https://meta.discourse.org/t/17247 for details
> expose:
> - "80:80" # http
> - "443:443" # https
>
> params:
> db_default_text_search_config: "pg_catalog.english"
>
> ## Set db_shared_buffers to a max of 25% of the total memory.
> ## will be set automatically by bootstrap based on detected RAM, or you can override
> db_shared_buffers: "256MB"
>
> env:
> LANG: en_US.UTF-8
> # DISCOURSE_DEFAULT_LOCALE: en
>
> ## How many concurrent web requests are supported? Depends on memory and CPU cores.
> ## will be set automatically by bootstrap based on detected CPUs, or you can override
> UNICORN_WORKERS: 3
>
> ## TODO: The domain name this Discourse instance will respond to
> DISCOURSE_HOSTNAME: 'discourse.example.com'
>
> ## Uncomment if you want the container to be started with the same
> ## hostname (-h option) as specified above (default "$hostname-$config")
> #DOCKER_USE_HOSTNAME: true
>
> ## TODO: List of comma delimited emails that will be made admin and developer
> ## on initial signup example 'user1@example.com,user2@example.com'
> DISCOURSE_DEVELOPER_EMAILS: 'user@example.com'
>
> ## TODO: The SMTP mail server used to validate new accounts and send notifications
> DISCOURSE_SMTP_ADDRESS: smtp.example.com # (mandatory)
> DISCOURSE_SMTP_PORT: 587 # (optional)
> DISCOURSE_SMTP_USER_NAME: user@example.com # (optional)
> DISCOURSE_SMTP_PASSWORD: a_s3cr3t_p@ssword # (optional)
> #DISCOURSE_SMTP_ENABLE_START_TLS: true # (optional, default true)
>
> ## If you added the Lets Encrypt template, uncomment below to get a free SSL certificate
> #LETSENCRYPT_ACCOUNT_EMAIL: me@example.com
>
> ## The CDN address for this Discourse instance (configured to pull)
> #DISCOURSE_CDN_URL: //discourse-cdn.example.com
>
> ## The Docker container is stateless; all data is stored in /shared
> volumes:
> - volume:
> host: /var/discourse/shared/standalone
> guest: /shared
> - volume:
> host: /var/discourse/shared/standalone/log/var-log
> guest: /var/log
>
> ## Plugins go here
> ## see https://meta.discourse.org/t/19157 for details
> hooks:
> after_code:
> - exec:
> cd: $home/plugins
> cmd:
> - git clone https://github.com/discourse/docker_manager.git
>
> ## Any custom commands to run after building
> run:
> - exec: echo "Beginning of custom commands"
> ## If you want to set the 'From' email address for your first registration, uncomment and change:
> #- exec: rails r "SiteSetting.notification_email='info@unconfigured.discourse.org'"
> ## After getting the first signup email, re-comment the line. It only needs to run once.
> - exec: echo "End of custom commands"
>
> ```
Letās get started with adding environmental variables to your site! š§
> ā¹ The following instructions are written for a [Standard Discourse Installation](https://github.com/discourse/discourse/blob/main/docs/INSTALL-cloud.md)
## Login to Your Server
Use a tool like PuTTY or the terminal on Unix-based systems to SSH into your server.
```plaintext
ssh username@your-server-ip
```
## Navigate to the Discourse Directory
Once you have access to your server, navigate to the directory containing your Discourse Docker setup, this is typically located at `/var/discourse`.
```plaintext
cd /var/discourse
```
## Open the `app.yml` File
Youāll need to open the `app.yml` file in a text editor. For this example weāll be using `nano`.
```plaintext
nano containers/app.yml
```
## Add Your Environmental Variables
In the `app.yml` file, youāll find an `env` section. This is where you can add your environmental variables.
```yml
env:
DISCOURSE_HOSTNAME: 'discourse.example.com'
DISCOURSE_SMTP_ADDRESS: smtp.example.com
DISCOURSE_SMTP_PORT: 587
DISCOURSE_SMTP_USER_NAME: user@example.com
DISCOURSE_SMTP_PASSWORD: a_s3cr3t_p@ssword
```
For example, if you wanted to set the `DISCOURSE_ENABLE_CORS` environmental variable to `true` to enable [Cross-Origin Resource Sharing (CORS)](https://meta.discourse.org/t/setup-cross-origin-resource-sharing-cors/270819), you would add the following line to the `env` section:
```plaintext
env:
DISCOURSE_ENABLE_CORS: "true"
...
```
> š The whitespace and formatting is important here, so make sure to maintain the correct indentation (two spaces) for the new line
Once youāve modified your variables, save and close the file.
## Rebuild the Discourse Container
Finally, youāll need to rebuild your Discourse Docker container for the changes to take effect. You can do this with the following command:
```plaintext
./launcher rebuild app
```
Alternatively, to update environmental variables for a running container without rebuilding, you can also use:
```plaintext
./launcher destroy app
./launcher start app
```
After the rebuild process completes, your updated environmental variables will be available to your Discourse application! š
> Last edited by @SaraDev 2024-08-16T20:01:37Z
>
> > **Check document**
> >
> > Perform check on document:
---
### Author:  [@pfaffman](https://meta.discourse.org/u/pfaffman)
#### Post date: [July 7, 2023, 4:18am UTC](https://meta.discourse.org/t/set-environmental-variables/270832/2 "2023-07-07T04:18:04Z")
This would be much more useful if it explained how to use env variables to override (and give from the UX) system settings or the global settings in the default global variable file (
and linked to it so people could see those settings like obscure redis settings
> [@SaraDev](#):
>
> For example, if you wanted to add a variable called `MY_VARIABLE` with a value of `my value`, you would add the following line:
>
> ```plaintext
> MY_VARIABLE: "my value"
>
> ```
This is a confusing example since it has nothing to do with discourse.
You could mention that itās the same as using the analogous command like setting in docker, perhaps.
I see you made this because you made [Setup Cross-Origin Resource Sharing (CORS)](https://meta.discourse.org/t/setup-cross-origin-resource-sharing-cors/270819), so maybe use that as an example.
---
### Author:  [@Crius](https://meta.discourse.org/u/Crius)
#### Post date: [July 8, 2023, 11:21am UTC](https://meta.discourse.org/t/set-environmental-variables/270832/4 "2023-07-08T11:21:11Z")
Is there a place in which one can find all the possible environment variable used in discourse?
**That** would have been much more useful rather than a topic that says that the environment variable go in the `app.yml` under the section `env:` š
Also, to have the application āloadā the changed environment variable, Iām pretty sure you can just `restart` and donāt need to `rebuild` but please someone correct me if Iām wrong.
---
### Author:  [@pfaffman](https://meta.discourse.org/u/pfaffman)
#### Post date: [July 8, 2023, 11:56am UTC](https://meta.discourse.org/t/set-environmental-variables/270832/5 "2023-07-08T11:56:45Z")
> [@Crius](#):
>
> Also, to have the application āloadā the changed environment variable, Iām pretty sure you can just `restart` and donāt need to `rebuild` but please someone correct me if Iām wrong.
You can destroy and start the container; thatās added to the OP, I think. The only issue is if you did upgrades from the UX they are lost.
You can set any site setting with DISCOURSE\_SETTING\_NAME. See also the default settings under config. [discourse/config/discourse\_defaults.conf at main Ā· discourse/discourse Ā· GitHub](https://github.com/discourse/discourse/blob/main/config/discourse_defaults.conf)
---
### Author:  [@Hyan](https://meta.discourse.org/u/Hyan)
#### Post date: [November 29, 2023, 1:03pm UTC](https://meta.discourse.org/t/set-environmental-variables/270832/6 "2023-11-29T13:03:47Z")
Hi @SaraDev, may I know how these environment variables change the behaviour of the Discourse? For example, all of variable mentioned in this post [Available settings for global rate limits and throttling](https://meta.discourse.org/t/available-settings-for-global-rate-limits-and-throttling/78612) I cannot find any of them in the Discouse source code, then how these variable are hooked to Discourse? Thanks!
---
### Author:  [@Arkshine](https://meta.discourse.org/u/Arkshine)
#### Post date: [November 29, 2023, 3:36pm UTC](https://meta.discourse.org/t/set-environmental-variables/270832/7 "2023-11-29T15:36:42Z")
> [@Hyan](#):
>
> I cannot find any of them in the Discouse source code
I believe you can see them here:
>
---
### Author:  [@Hyan](https://meta.discourse.org/u/Hyan)
#### Post date: [November 30, 2023, 12:17am UTC](https://meta.discourse.org/t/set-environmental-variables/270832/8 "2023-11-30T00:17:33Z")
Thank you so much @Arkshine.
---
### Author:  [@ewd910](https://meta.discourse.org/u/ewd910)
#### Post date: [January 15, 2024, 5:11pm UTC](https://meta.discourse.org/t/set-environmental-variables/270832/9 "2024-01-15T17:11:31Z")
Is there a way to set environment variables on a non-docker hosted dev environment? I plan on hosting with docker eventually but am developing locally with this setup: [Install Discourse on macOS for development](https://meta.discourse.org/t/install-discourse-on-macos-for-development/15772)
Thereās no app.yml in this case
---
### Author:  [@pfaffman](https://meta.discourse.org/u/pfaffman)
#### Post date: [January 15, 2024, 6:23pm UTC](https://meta.discourse.org/t/set-environmental-variables/270832/10 "2024-01-15T18:23:40Z")
> [@ewd910](#):
>
> Is there a way to set environment variables on a non-docker hosted dev environment?
You can set them in the command line before you start rails, but what are you trying to do with those ENV variables?
---
### Author:  [@ewd910](https://meta.discourse.org/u/ewd910)
#### Post date: [January 15, 2024, 10:39pm UTC](https://meta.discourse.org/t/set-environmental-variables/270832/11 "2024-01-15T22:39:42Z")
Iām trying to set DISCOURSE\_ENABLE\_CORS to true for SSO. Would you mind sending me a sample command? Iām new to discourse / rails development. Also what does that ultimately do? Create a record in the site\_settings table?
---
### Author:  [@MaxSPG](https://meta.discourse.org/u/MaxSPG)
#### Post date: [February 7, 2024, 1:16pm UTC](https://meta.discourse.org/t/set-environmental-variables/270832/12 "2024-02-07T13:16:07Z")
I am trying to setup discourse automatically within kubernetes. Therefore I plan to build a custom docker image (DinD).
BUT if I were to run ./discourse-setup.sh in my Dockerfile, it would ask me for config options - which docker can not answer (as this should be done automatically).
I understand that I could put those env variables inside the app.yml file, but at this point there will not be any app.yaml file at all, as the ./discourse-setup script has not been run yet.
So my question would be: How can I pre-configure discourse for my purposes, so that ./discourse-setup does not require my user input?
The [discourse/docs/INSTALL-cloud.md at main Ā· discourse/discourse (github.com)](https://github.com/discourse/discourse/blob/main/docs/INSTALL-cloud.md) install guide does not say anything about pre-configurations or config files at all.
Thanks in advance!
---
### Author:  [@pfaffman](https://meta.discourse.org/u/pfaffman)
#### Post date: [February 7, 2024, 6:43pm UTC](https://meta.discourse.org/t/set-environmental-variables/270832/13 "2024-02-07T18:43:40Z")
Try
```plaintext
./launcher start-cmd app
```
Thatāll give you the docker start command used to crank up the container. You should be able to use that to figure out how to crank things up in k8s.
---
### Author:  [@swong](https://meta.discourse.org/u/swong)
#### Post date: [May 14, 2024, 12:33am UTC](https://meta.discourse.org/t/set-environmental-variables/270832/14 "2024-05-14T00:33:36Z")
> [@SaraDev](#):
>
> Once you have access to your server, navigate to the directory containing your Discourse Docker setup, this is typically located at `/var/discourse`
Are there any other common places that `app.yml` file could live, or could it be possible that this file needs to be created from scratch? I āwent intoā my Docker container (`docker exec -it discourse_dev /bin/bash`), and was unable to find any file named `app.yml`.
---
### Author:  [@Firepup650](https://meta.discourse.org/u/Firepup650)
#### Post date: [May 14, 2024, 2:04am UTC](https://meta.discourse.org/t/set-environmental-variables/270832/15 "2024-05-14T02:04:53Z")
The `app.yml` file should be outside of your container, rather than inside of it.