docs - update troubleshooting section (#17236)

docs/troubleshooting-guide/application-database.md

-# The Metabase Application Database
+# Trouble with the Metabase Application Database
 
-Metabase stores information about users, questions, and so on in a database of its own that we call the "application database". If the application cannot do this, it will not run.
-
-## Specific Problems
+Metabase stores information about users, questions, and so on in a database of its own that we call the "application database". The default application database that ships with Metabase is an [H2 database][what-is-h2], which is not recommended for production. To use a production-ready database for you Metabase application database, see [Migrating from H2][migrating]. 
 
 ### Metabase fails to start due to database locks
 
@@ -68,3 +66,4 @@ Exception in thread "main" java.lang.AssertionError: Assert failed: Unable to co
 **How to fix this:** You can unblock the file by right-clicking on it, clicking "Properties," and then clicking "Unblock." 
 
 [what-is-h2]: ../faq/setup/what-is-h2.html
+[migrating]: ../operations-guide/migrating-from-h2.html
\ No newline at end of file

docs/troubleshooting-guide/index.md

 # What are you having trouble with?
 
-- [Logging in](./loggingin.html)
+This page collects resources for getting you unstuck.
 
-- [Running Metabase](./running.html)
+## Troubleshooting guides
 
-- [Running Metabase on Docker](./docker.html)
+Problems, their causes, how to detect them, and how to fix them.
 
-- [My question or dashboard is slow](performance.html)
+### Using Metabase
 
-- [The Metabase Application Database](./application-database.html)
+- [Logging in][login].
 
-- [Connecting to data warehouses with Metabase](./datawarehouse.html)
+- [Saving questions or dashboards][proxies].
 
-- [Timezone problems](./timezones.html)
+- [My question or dashboard is slow][performance].
 
-- [Can't save questions or dashboards, or getting a blank page](./proxies.html)
+### Setup and administration
 
-- [LDAP](./ldap.html)
+- [Running the Metabase JAR][running].
 
-- [Email](./email.html)
+- [Running Metabase on Docker][docker].
 
-- [I think I found a bug](./bugs.html)
+- [Connecting to data warehouses with Metabase][datawarehouse].
 
-## Helpful tidbits
+- [Loading an exported application database][loadh2].
 
-### Accessing the Metabase server logs
+- [Setting up LDAP][ldap].
 
-You can always look for the logs that Metabase leaves on your server's file system (or wherever else you collect logs). If you're logged into Metabase with an admin account, you can also access the logs from the **Logs** tab in the **Troubleshooting** section of the **Admin Panel**. To get to the Admin Panel, click the **gear icon** in the top-right of Metabase.
+- [Setting up Email][email].
 
-### Checking for Javascript console errors
+- [Using the default H2 application database][appdb].
 
-Metabase will send debugging information and errors to your browser's developer console. To open the developer console, follow the instructions for your web browser of choice:
+- [Handling timezones][timezones].
 
-- [Chrome](https://developers.google.com/web/tools/chrome-devtools/open#console)
-- [Firefox](https://developer.mozilla.org/en-US/docs/Tools/Web_Console/Opening_the_Web_Console)
-- [Safari](https://support.apple.com/guide/safari-developer/develop-menu-dev39df999c1/mac)
-- [Edge](https://docs.microsoft.com/en-us/microsoft-edge/devtools-guide-chromium)
+- [Manage data sandboxing][sandbox]
+
+## Think you found a bug?
+
+Let us know by [filing a bug report][bugs].
+
+## More troubleshooting resources
+
+Here are some other resources to help you solve your problem or find a workaround.
+
+### Metabase server and console logs
+
+Metabase will log errors, both on the server and in the browser console, depending on where the error occurs, which can help you track down an issue. Administrators will have access to the server logs, and everyone with a browser can open the developer tools to see the console logs.
+
+**Accessing the Metabase server logs**: You can look for the logs that Metabase leaves on the server's file system (or wherever else you collect logs). If you're logged into Metabase with an Admin account, you can also access the logs by clicking on the **gears icon** in the top right of the main nav, selecting **Admin**, clicking on the **Troubleshooting** tab, then viewing the **Logs** tab.
+
+**Checking for Javascript console errors:** Metabase will send debugging information and errors to your browser's developer console. To open the developer console, follow the instructions for web browser:
+
+- [Chrome][chrome]
+- [Firefox][firefox]
+- [Safari][safari]
+- [Edge][edge]
+
+### Metabase tutorials 
+
+For tutorials that walk you through how to use Metabase features, check out [Learn Metabase][learn].
+
+### Metabase forum
+
+To see if someone else has run into a similar issue, check out [our forum on Discourse][forum].
+
+### Frequently asked questions
+
+For quick answers to common questions, check out our [Frequently Asked Questions][faq].
+
+### Upgrading Metabase
+
+Metabase adds new features and squashes bugs with each release. [Upgrading to the latest and greatest][upgrade] may resolve your issue. If you're using [Metabase Cloud][cloud], we'll handle the upgrades for you. You can checkout the [release notes][releases] to see what's new.
+
+[appdb]: ./application-database.html
+[bugs]: ./bugs.html
+[chrome]: https://developers.google.com/web/tools/chrome-devtools/open#console
+[cloud]: https://www.metabase.com/start/ 
+[datawarehouse]: ./datawarehouse.html
+[docker]: ./docker.html
+[edge]: https://docs.microsoft.com/en-us/microsoft-edge/devtools-guide-chromium
+[email]: ../operations-guide/upgrading-metabase.html
+[faq]: /faq
+[firefox]: https://developer.mozilla.org/en-US/docs/Tools/Web_Console/Opening_the_Web_Console
+[forum]: https://discourse.metabase.com/
+[ldap]: ./ldap.html
+[learn]: https://www.metabase.com/learn
+[login]: ./loggingin.html
+[loadh2]: ./loading-from-h2.html
+[performance]: ./performance.html
+[proxies]: ./proxies.html
+[releases]: https://github.com/metabase/metabase/releases
+[running]: ./running.html
+[sandbox]: ./sandboxing.html
+[safari]: https://support.apple.com/guide/safari-developer/develop-menu-dev39df999c1/mac
+[timezones]: ./timezones.html
+[upgrade]: ../operations-guide/upgrading-metabase.html
\ No newline at end of file

docs/troubleshooting-guide/ldap.md

 # LDAP
 
-Metabase can use LDAP for authentication. [This article][ldap-learn] explains how to set it up, and the guide below will help you troubleshoot if anything goes wrong.
+Metabase can use LDAP for authentication. [This article][ldap-learn] explains how to set it up, and the guide below will help you troubleshoot if anything goes wrong. You may also want to check [our troubleshooting guide for logging in](./loggingin.html).
 
-## Troubleshooting Process
-
-FIXME
-
-You may also want to check [our troubleshooting guide for logging in](./loggingin.html).
-
-### LDAP sample configuration
+## LDAP sample configuration
 
 You can test Metabase with LDAP by using this `docker-compose` definition:
 
@@ -69,11 +63,11 @@ If you don't pass environment variables to Metabase and you want to configure th
 
 For the `USER FILTER`, you can leave the default value, which will look for the user ID in both the `uid` or `email` field.
 
-### Related software for troubleshooting
+## Related software for troubleshooting
 
 If you run into an issue, check that you can login to your LDAP directory and issue queries using software like [Apache Directory Studio][apache-directory-studio]. It will let you see the whole LDAP tree and view the logs of your LDAP application to see queries run.
 
-### Current limitations
+## Current limitations
 
 - When using Metabase Enterprise with a MySQL database and LDAP enabled, make sure that you disable synchronization of binary fields from your LDAP directory by using the `MB_LDAP_SYNC_USER_ATTRIBUTES_BLACKLIST` environment variable. If you do not, you may hit the 60K field size limitation of the text field in MySQL, which will prevent you from creating users or those users from logging in.
 

docs/troubleshooting-guide/performance.md

@@ -70,7 +70,7 @@ Joining half a dozen tables, each with a few million rows, simply takes a lot of
 
 3. If the query runs slowly when sent by another tool, see if you can write a SQL query that calculates the same result as the question you have built in Metabase, but does so more quickly.
 
-**How to fix this:* If the problem is the SQL we generate:
+**How to fix this:** If the problem is the SQL we generate:
 
 1. Check if you have the most recent version of Metabase: we fix problems as they're reported, and updating Metabase may make your problem go away.
 2. You can use your SQL in place of the code we generate, and [make its result available][organizing-sql] to people who prefer the Notebook Editor as a starting point for their questions.