docs(help): document backend logs retention

docs/User Guide/User Guide/Troubleshooting/Error logs.md

@@ -1,28 +1,10 @@
 # Error logs
-It's important to provide all available error logs together with bug reports. This page will show you how to do it.
+It's important to provide all available error logs together with bug reports.
 
-## Backend logs
+There are two types of error logs, both of which are useful when reporting bugs.
 
-Open [data directory](../Installation%20%26%20Setup/Data%20directory.md), go to `log` subdirectory and find the latest log file, e.g. `trilium-2022-12-14.log`. You can attach the whole file to the bug report (preferable) or open it and copy-paste only the last lines / lines you believe are relevant.
-
-If you have trouble finding it the log files, there's also an in-app option in top-left menu button -> Advanced -> Show backend log.
-
-## Frontend logs
-
-To provide frontend logs, we need to open the Developer Console. Often the easiest way is to press <kbd>Ctrl</kbd>\-<kbd>Shift</kbd>\-<kbd>I</kbd> which should work in most browsers (and desktop app). Make sure that the error producing action happened right before you copy&paste the errors, the console is cleared on app restart.
-
-If that doesn't work, then:
-
-*   in Trilium desktop app, go to top-left menu button -> Advanced -> Open Dev Tools
-*   In Firefox/Chrome right-click anywhere in the page and click Inspect:
-
-![](Error%20logs_error-logs-fire.png)
-
-Once you have Dev Tools open, click on "Console" tab:
-
-![](Error%20logs_image.png)
-
-Copy-paste (or screenshot) the logs. It's better to provide not just errors, but the whole log, which might provide context while analyzing the bug.
+*   <a class="reference-link" href="Error%20logs/Backend%20(server)%20logs.md">Backend (server) logs</a>
+*   <a class="reference-link" href="Error%20logs/Frontend%20logs.md">Frontend logs</a>
 
 ## Providing sensitive data
 

docs/User Guide/User Guide/Troubleshooting/Error logs/Backend (server) logs.md

@@ -0,0 +1,28 @@
+# Backend (server) logs
+## Accessing via the backend log
+
+In the <a class="reference-link" href="../../Basic%20Concepts%20and%20Features/UI%20Elements/Global%20menu.md">Global menu</a>, go to Advanced → Show backend log
+
+## Location on the disk
+
+Backend logs are stored on the file system. To find them, open the <a class="reference-link" href="../../Installation%20%26%20Setup/Data%20directory.md">Data directory</a>, go to the `log` subdirectory and find the latest log file, e.g. `trilium-2022-12-14.log`. 
+
+## Reporting backend bugs
+
+You can attach the whole file to the bug report (preferable) or open it and copy-paste only the last lines / lines you believe are relevant.
+
+## Customizing the retention of logs
+
+The backend logs are fully managed by the Trilium server. By default the last 90 days worth of logs are kept; the logs older than that are deleted in order to reduce the space consumption.
+
+It's possible to change the retention period by modifying the <a class="reference-link" href="../../Advanced%20Usage/Configuration%20(config.ini%20or%20e.md">Configuration (config.ini or environment variables)</a> via the `.ini` file:
+
+```
+[Logging]
+retentionDays=7
+```
+
+Or via the environment variable `TRILIUM_LOGGING_RETENTION_DAYS`.
+
+> [!NOTE]
+> If you set the retention days to a low number, you might notice that not all the log files are being deleted. This is because a minimum number of logs (7 at the time of writing) is maintained at all times.

docs/User Guide/User Guide/Troubleshooting/Error logs/Frontend logs.md

@@ -0,0 +1,15 @@
+# Frontend logs
+To provide frontend logs, we need to open the Developer Console. Often the easiest way is to press <kbd>Ctrl</kbd>\-<kbd>Shift</kbd>\-<kbd>I</kbd> which should work in most browsers (and desktop app). Make sure that the error producing action happened right before you copy&paste the errors, the console is cleared on app restart.
+
+If that doesn't work, then:
+
+*   in Trilium desktop app, go to top-left menu button -> Advanced -> Open Dev Tools
+*   In Firefox/Chrome right-click anywhere in the page and click Inspect:
+
+![](Frontend%20logs_error-logs-f.png)
+
+Once you have Dev Tools open, click on "Console" tab:
+
+![](Frontend%20logs_image.png)
+
+Copy-paste (or screenshot) the logs. It's better to provide not just errors, but the whole log, which might provide context while analyzing the bug.