docs: update Synology install guide (#21996)

Co-authored-by: mertalev <101130780+mertalev@users.noreply.github.com>

docs/docs/install/synology.md

@@ -16,7 +16,7 @@ Immich can easily be installed on a Synology NAS using Container Manager within
 
 ## Step 1 - Download the required files
 
-Create a directory of your choice (e.g. `./immich-app`) to house Immich. In general, it's a best practice to have all Docker-based applications running under the `./docker` directory, so in this case, your directory structure will look like `./docker/immich-app`.
+Create a directory of your choice (e.g. `./immich-app`) to house Immich. In general, it's best practice to have all Docker-based applications running under the `./docker` directory, so in this case, your directory structure will look like `./docker/immich-app`.
 
 Now create a `./postgres` and `./library` directory as sub-directories of the `./docker/immich-app`.
 
@@ -25,7 +25,7 @@ When you're all done, you should have the following:
 - `./docker/immich-app/postgres`
 - `./docker/immich-app/library`
 
-Download [`docker-compose.yml`](https://github.com/immich-app/immich/releases/latest/download/docker-compose.yml) and [`example.env`](https://github.com/immich-app/immich/releases/latest/download/example.env) to your computer. Upload the files to the `./docker/immich-app` directory, and rename `example.env` to `.env`.
+Download [`docker-compose.yml`](https://github.com/immich-app/immich/releases/latest/download/docker-compose.yml) and [`example.env`](https://github.com/immich-app/immich/releases/latest/download/example.env) to your computer. Upload the files to the `./docker/immich-app` directory, and rename `example.env` to `.env`. Note: If you plan to use the Synology Text editor to edit the `.env` file on the NAS within File Station, you will need to rename it to a temporary name (e.g. `example.txt`) in order to see 'Open with Text Editor' in the file context menu. Once saved, rename it back to `.env`.
 
 ## Step 2 - Populate the .env file with custom values
 
@@ -34,23 +34,23 @@ Follow [Step 2 in Docker Compose](/install/docker-compose#step-2---populate-the-
 ## Step 3 - Create a new project in Container Manager
 
 Open Container Manager, and select the "**Project**" action on the left navigation bar and then click "**Create**".
-![Create Project](../../static/img/synology-container-manager-create-project.png)
+![Create project](../../static/img/synology-container-manager-create-project.png)
 
 In the settings of your new project, set "**Project name**" to a name you'll remember, such as _immich-app_. When setting the "**Path**", select the `./docker/immich-app` directory you created earlier. Doing so will prompt a message to use the existing `docker-compose.yml` already present in the directory for your project. Click "**OK**" to continue.
 
-![Set Path](../../static/img/synology-container-manager-set-path.png)
+![Set path](../../static/img/synology-container-manager-set-path.png)
 
-The following screen will give you the option to further customize your `docker-compose.yml` file, giving you a warning regarding the `start_interval` property. Under the `healthcheck` heading, remove the `start_interval: 30s` completely and click "**Next**".
+The following screen will give you the option to further customize your `docker-compose.yml` file. Take note of `DB_STORAGE_TYPE: 'HDD'`and uncomment if applicable for your Synology setup.
 
-![start interval](../../static/img/synology-container-manager-customize-docker-compose.png)
+![DB storage](../../static/img/synology-container-manager-customize-docker-compose.png)
 
 Skip the section asking to set-up a portal for Web Station, and then complete the wizard which will build and start the containers for your project.
 
 Once your containers are successfully running, navigate to the "**Container**" section of Container Manager, right-click on the "**immich-server**" container, and choose the "**Details**".
 
-Scroll to the bottom of the "**Details**" section, and find the `IP Address` of the container, located in the `Network` section. Take note of the container's IP address as you will need it for **Step 4**.
+Scroll to the bottom of the "**Details**" section and find the `IP Address` listed in the `Network` section. Take note of the container's IP address as you will need it for **Step 4**.
 
-![Container Details](../../static/img/synology-container-manager-container-details.png)
+![Container details](../../static/img/synology-container-manager-container-details.png)
 
 ## Step 4 - Configure Firewall Settings
 
@@ -63,8 +63,66 @@ Open "**Control Panel**" on your Synology NAS, and select "**Security**". Naviga
 Click "**Edit Rules**" and add the following firewall rules:
 
 - Add a "**Source IP**" rule for the IP address of your container that you obtained in Step 3 above
+
+![IP address rule](../../static/img/synology-ipaddress-firewall-rule.png)
+
 - Add a "**Ports**" rule for the port specified in the `docker-compose.yml`, which should be `2283`
 
+![Custom port rule](../../static/img/synology-custom-port-firewall-rule.png)
+
 ## Next Steps
 
 Read the [Post Installation](/install/post-install.mdx) steps and [upgrade instructions](/install/upgrading.md).
+
+<details>
+  <summary>Updating Immich using Container Manager</summary>
+Check the post installation and upgrade instructions at the links above before proceeding with this section.
+
+## Step 1. Backup
+
+Ensure your photos and videos are backed up. Your `.env` settings will define where they are stored. There is no need to delete any files or folders within the `docker` folder when doing a release upgrade unless instructed in the release notes.
+
+## Step 2. Check release notes
+
+Always check the [release notes](https://github.com/immich-app/immich/releases) before proceeding with an update!
+
+## Step 3. Stop containers & clean up
+
+Open **Container Manager**. Select **Project** then your Immich app
+
+![Select project](../../static/img/synology-select-proj.png)
+
+Select **Stop**
+
+![Stop project](../../static/img/synology-project-stop.png)
+
+Select **Action** then **Clean**. This removes the containers.
+
+![Clean project](../../static/img/synology-action-clean.png)
+
+Go to **Image** and select **Remove Unused Images**.
+
+![Remove unused](../../static/img/synology-remove-unused.png)
+
+## Step 4. Build
+
+Go to **Project**, select **Action** then **Build**. This will download, unpack, install and start the containers.
+
+![Build](../../static/img/synology-build.png)
+
+## Step 5. Update firewall rule
+
+The default behavior is to automatically start the containers once installed. If `immich_server` runs for a few seconds and then stops, it may be because the firewall rule no longer matches the server IP address.
+
+Go to the **Container** section. Click on `immich_server` and scroll down on **General** to find the IP address.
+![Container IP](../../static/img/synology-container-ip.png)
+
+Go to Synology **Control Panel**. Select **Security** and **Firewall**.
+
+![Firewall](../../static/img/synology-fw-rules.png)
+
+In this example, the IP addresses mismatch and the firewall rule needs to be edited to match above.
+
+![Edit IP](../../static/img/synology-fw-ipedit.png)
+
+</details>