engine: rename systemd.md to proxy.md, update links

Signed-off-by: David Karlsson <35727626+dvdksn@users.noreply.github.com>

content/config/containers/resource_constraints.md

@@ -233,7 +233,9 @@ for real-time tasks per runtime period. For instance, with the default period of
 containers using the real-time scheduler can run for 950000 microseconds for every
 1000000-microsecond period, leaving at least 50000 microseconds available for
 non-real-time tasks. To make this configuration permanent on systems which use
-`systemd`, see [Control and configure Docker with systemd](../daemon/systemd.md).
+`systemd`, create a systemd unit file for the `docker` service. For an example,
+see the instruction on how to configure the daemon to use a proxy with a
+[systemd unit file](../daemon/proxy.md#systemd-unit-file).
 
 #### Configure individual containers
 

content/config/daemon/_index.md

@@ -127,4 +127,4 @@ documentation. Some places to go next include:
 - [Limit a container's resources](../containers/resource_constraints.md)
 - [Configure storage drivers](../../storage/storagedriver/select-storage-driver.md)
 - [Container security](../../engine/security/_index.md)
-- [Configure the Docker daemon to use a proxy](./systemd.md#httphttps-proxy)
+- [Configure the Docker daemon to use a proxy](./proxy.md)

content/config/daemon/proxy.md

@@ -7,6 +7,7 @@ aliases:
   - /articles/systemd/
   - /engine/admin/systemd/
   - /engine/articles/systemd/
+  - /config/daemon/systemd/
 ---
 
 <a name="httphttps-proxy"><!-- included for deep-links to old section --></a>
@@ -61,6 +62,8 @@ environment to configure HTTP or HTTPS proxy behavior:
 - `NO_PROXY`
 - `no_proxy`
 
+### systemd unit file
+
 If you're running the Docker daemon as a systemd service, you can create a
 systemd drop-in file that sets the variables for the `docker` service.
 

content/config/daemon/troubleshoot.md

@@ -60,7 +60,7 @@ ExecStart=/usr/bin/dockerd
 ```
 
 There are other times when you might need to configure `systemd` with Docker,
-such as [configuring a HTTP or HTTPS proxy](systemd.md#httphttps-proxy).
+such as [configuring a HTTP or HTTPS proxy](./proxy.md).
 
 > **Note**
 >

content/engine/install/linux-postinstall.md

@@ -96,7 +96,7 @@ To create the `docker` group and add your user:
 
 ## Configure Docker to start on boot with systemd
 
-Many modern Linux distributions use [systemd](../../config/daemon/systemd.md) to
+Many modern Linux distributions use [systemd](https://systemd.io/) to
 manage which services start when the system boots. On Debian and Ubuntu, the
 Docker service starts on boot by default. To automatically start Docker and
 containerd on boot for other Linux distributions using systemd, run the
@@ -114,9 +114,10 @@ $ sudo systemctl disable docker.service
 $ sudo systemctl disable containerd.service
 ```
 
-If you need to add an HTTP proxy, set a different directory or partition for the
-Docker runtime files, or make other customizations, see
-[customize your systemd Docker daemon options](../../config/daemon/systemd.md).
+You can use systemd unit files to configure the Docker service on startup,
+for example to add an HTTP proxy, set a different directory or partition for the
+Docker runtime files, or other customizations. For an example, see
+[Configure the daemon to use a proxy](../../config/daemon/proxy.md#systemd-unit-file).
 
 ## Configure default logging driver
 

content/engine/release-notes/20.10.md

@@ -405,7 +405,7 @@ to learn how to use the `docker scan` command to check if images are vulnerable.
 > longer used for TLS (`https://`) connections. Make sure you also set an `$HTTPS_PROXY`
 > environment variable for handling requests to `https://` URLs.
 >
-> Refer to the [HTTP/HTTPS proxy section](../../config/daemon/systemd.md#httphttps-proxy)
+> Refer to [Configure the daemon to use a proxy](../../config/daemon/proxy.md)
 > to learn how to configure the Docker Daemon to use a proxy server.
 { .important }
 
@@ -435,7 +435,7 @@ to learn how to use the `docker scan` command to check if images are vulnerable.
 > longer used for TLS (`https://`) connections. Make sure you also set an `$HTTPS_PROXY`
 > environment variable for handling requests to `https://` URLs.
 >
-> Refer to the [HTTP/HTTPS proxy section](../../config/daemon/systemd.md#httphttps-proxy)
+> Refer to the [HTTP/HTTPS proxy section](../../config/daemon/proxy.md#httphttps-proxy)
 > to learn how to configure the Docker Daemon to use a proxy server.
 { .important }
 
@@ -476,7 +476,7 @@ well as updated versions of the containerd.io package.
 > longer used for TLS (`https://`) connections. Make sure you also set an `$HTTPS_PROXY`
 > environment variable for handling requests to `https://` URLs.
 >
-> Refer to the [HTTP/HTTPS proxy section](../../config/daemon/systemd.md#httphttps-proxy)
+> Refer to the [HTTP/HTTPS proxy section](../../config/daemon/proxy.md#httphttps-proxy)
 > to learn how to configure the Docker Daemon to use a proxy server.
 { .important }
 
@@ -521,7 +521,7 @@ well as updated versions of the containerd.io package.
 > longer used for TLS (`https://`) connections. Make sure you also set an `$HTTPS_PROXY`
 > environment variable for handling requests to `https://` URLs.
 >
-> Refer to the [HTTP/HTTPS proxy section](../../config/daemon/systemd.md#httphttps-proxy)
+> Refer to the [HTTP/HTTPS proxy section](../../config/daemon/proxy.md#httphttps-proxy)
 > to learn how to configure the Docker Daemon to use a proxy server.
 { .important }
 

content/network/proxy.md

@@ -14,7 +14,7 @@ For instructions on configuring Docker Desktop to use HTTP/HTTPS proxies, see
 [proxies on Linux](../desktop/settings/linux.md#proxies).
 
 If you're running Docker Engine without Docker Desktop, refer to
-[Configure the Docker daemon to use a proxy server](../config/daemon/systemd.md#httphttps-proxy)
+[Configure the Docker daemon to use a proxy](../config/daemon/proxy.md)
 to learn how to configure a proxy server for the Docker daemon (`dockerd`) itself.
 
 If your container needs to use an HTTP, HTTPS, or FTP proxy server, you can
@@ -79,7 +79,7 @@ These settings are used to configure proxy environment variables for containers
 only, and not used as proxy settings for the Docker CLI or the Docker Engine
 itself.
 Refer to the [environment variables](/engine/reference/commandline/cli/#environment-variables)
-and [configure the Docker daemon to use a proxy server](../config/daemon/systemd.md#httphttps-proxy)
+and [configure the Docker daemon to use a proxy server](../config/daemon/proxy.md#httphttps-proxy)
 sections for configuring proxy settings for the CLI and daemon.
 
 ### Run containers with a proxy configuration

data/toc.yaml

@@ -1637,8 +1637,8 @@ Manuals:
       title: Start the daemon
     - path: /config/daemon/
       title: Configure the daemon
-    - path: /config/daemon/systemd/
-      title: Configure with systemd
+    - path: /config/daemon/proxy/
+      title: HTTP proxy
     - path: /config/containers/live-restore/
       title: Live restore
     - path: /config/daemon/troubleshoot/