docs: add environment variables configuration method for Docker daemon#25075
Open
mohithshuka wants to merge 3 commits into
Open
docs: add environment variables configuration method for Docker daemon#25075mohithshuka wants to merge 3 commits into
mohithshuka wants to merge 3 commits into
Conversation
added 3 commits
May 15, 2026 16:36
The previous description said 'optimize your repository storage' which was vague and did not reflect the page's actual content. The manage.md page is focused on viewing, filtering, and deleting images and image indexes. Updated the description to accurately reflect this. Fixes docker#25005
The daemon configuration overview only mentioned two methods (JSON file and flags) but was missing the environment variables method via systemd. Added a new section explaining how to use systemd drop-in overrides to set daemon environment variables. Fixes docker#25062
✅ Deploy Preview for docsdocker ready!
To edit notification comments on pull requests, go to your Netlify project configuration. |
Contributor
There was a problem hiding this comment.
Pull request overview
Addresses issue #25062 by expanding the Docker daemon configuration overview to mention environment variables as an additional configuration method, and adds a new "Configuration using environment variables" section showing a systemd drop-in example.
Changes:
- Updates the intro list from "two ways" to "three ways" and adds an environment-variables bullet.
- Adds a new section demonstrating
systemctl edit dockerwith anEnvironment="DOCKER_OPTS=..."drop-in and a reload/restart sequence.
Comments suppressed due to low confidence (3)
content/manuals/engine/daemon/_index.md:49
- The list now describes three configuration methods, but the sentence below still says "both of these options together," which only refers to two. This should be updated to reflect that three methods exist (e.g., "You can combine these options...") and clarify how environment variables interact with the JSON file and flags.
You can use both of these options together as long as you don't specify the same
option both as a flag and in the JSON file. If that happens, the Docker daemon
won't start and prints an error message.
content/manuals/engine/daemon/_index.md:113
- The opening fence uses 6 backticks while the closing fence uses 5, so the code block is unbalanced and will not render correctly. Use matching fences (typically 3 backticks) on both sides.
``````ini
[Service]
Environment="DOCKER_OPTS=--debug --tls=true"
**content/manuals/engine/daemon/_index.md:120**
* The opening fence uses 4 backticks while the closing fence uses 3, leaving the code block unbalanced. Use matching fences on both ends.
$ sudo systemctl daemon-reload
$ sudo systemctl restart docker
```
```
</details>
---
💡 <a href="/docker/docs/new/main?filename=.github/instructions/*.instructions.md" class="Link--inTextBlock" target="_blank" rel="noopener noreferrer">Add Copilot custom instructions</a> for smarter, more guided reviews. <a href="https://docs.github.com/en/copilot/customizing-copilot/adding-repository-custom-instructions-for-github-copilot" class="Link--inTextBlock" target="_blank" rel="noopener noreferrer">Learn how to get started</a>.
Comment on lines
+104
to
+106
| ````````console | ||
| $ sudo systemctl edit docker | ||
| ``````` |
Comment on lines
+96
to
+120
| ### Configuration using environment variables | ||
|
|
||
| You can configure the Docker daemon using environment variables. This is useful | ||
| in systemd service overrides or init scripts. | ||
|
|
||
| To set environment variables for the Docker daemon using systemd, create a | ||
| drop-in override file: | ||
|
|
||
| ````````console | ||
| $ sudo systemctl edit docker | ||
| ``````` | ||
|
|
||
| Add the following: | ||
|
|
||
| ``````ini | ||
| [Service] | ||
| Environment="DOCKER_OPTS=--debug --tls=true" | ||
| ````` | ||
|
|
||
| Then reload and restart the daemon: | ||
|
|
||
| ````console | ||
| $ sudo systemctl daemon-reload | ||
| $ sudo systemctl restart docker | ||
| ``` |
| - Use a JSON configuration file. This is the preferred option, since it keeps | ||
| all configurations in a single place. | ||
| - Use flags when starting `dockerd`. | ||
| - Use environment variables to set daemon options. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
What changed
Added a new "Configuration using environment variables" section to the
Docker daemon configuration overview page.
Why
The page stated there are "two ways" to configure the Docker daemon
(JSON file and flags) but was missing the environment variables method
using systemd drop-in overrides.
Fixes #25062
Testing