update

Author: Barb Cutler

_docs/sysadmin/installation/version_notes/v23.02.XX.md

@@ -0,0 +1,88 @@
+---
+title:  v23.12.02 > Apache2 HTTP/2 Support
+category: System Administrator > Installation Version Notes
+redirect_from:
+  - /system_admin/version_notes/v23.12.02
+---
+
+Release [v23.12.02](https://github.com/Submitty/Submitty/releases/v23.12.02)
+includes an update to the Apache2 server's module and configuration to
+disable `php8.1` and `mpm_prefork` and enable `mpm_event` and `http2`.
+Note:  Submitty uses `php8.1-fpm` NOT `php8.1`.
+
+
+1. If you have load balancers and firewalls in front of the Apache
+   server for Submitty, please make sure they support HTTP/2
+   redirections.
+
+2. Disable `php8.1` and `mpm_prefork`:
+
+   ```
+   a2dismod php8.1 mpm_prefork
+   ```
+
+3. Enable `mpm_event` and `http2`:
+
+   ```
+   a2enmod mpm_event http2
+   ```
+
+4. If you are not already using TLS/SSL HTTPS encryption for Submitty,
+   we strongly recommend enabling it.  See 
+   [System Administrator Installation Instructions](https://submitty.org/sysadmin/installation/index).
+
+5. Review your current performance tuning for `php-fpm`.  
+   ```
+   /etc/php/8.1/fpm/pool.d/submitty.conf
+   ```
+   You will probably not need to change these settings.
+
+6. With the switch from `mpm_prefork` to `mpm_event`, you will probably want to take any customization from this file:
+   ``` 
+   /etc/apache2/mods-available/mpm_prefork.conf
+   ```
+
+   And adapt it to this file:
+   ```
+   /etc/apache2/mods-available/mpm_event.conf
+   ```
+   
+6. Final check for Apache2's configuration;
+   ```sh
+   apachectl -t
+   ```
+
+7. Reload Apache2 to apply changes.
+
+   ```
+   sudo systemctl restart apache2.service
+   sudo systemctl restart php8.1-fpm
+   ```
+
+8. Run the update script.
+
+   ```
+   sudo /usr/local/submitty/.setup/INSTALL_SUBMITTY.sh
+   ```
+   
+---
+
+NOTE:  If you need to downgrade from HTTP/2 back to HTTP/1.1 and re-enable `mpm_prefork`,
+please follow the steps below:
+
+1. Disable `http2` and `mpm_event`:
+
+   ```
+   a2dismod http2 mpm_event
+   ```
+
+2. Enable `mpm_prefork`:
+
+   ```
+   a2enmod mpm_prefork
+   ```
+
+3. Alternatively, if the PHP does not use a `fpm` server, consider enabling
+   `php8.1` by `a2enmod php8.1`.
+
+

_docs/sysadmin/installation/version_notes/v23.12.02.md

@@ -145,6 +145,7 @@ var NAVTREE =
                 [ "Update Submitty", "/sysadmin/installation/update_submitty", null ],
                 [ "Version Notes", "/sysadmin/installation/version_notes/index", [
                     [ "Overview", "/sysadmin/installation/version_notes/index", null],
+                    [ "v23.12.02", "/sysadmin/installation/version_notes/v23.12.02", null ],
                     [ "v23.07.00", "/sysadmin/installation/version_notes/v23.07.00", null ],
                     [ "v23.03.01", "/sysadmin/installation/version_notes/v23.03.01", null ],
                     [ "v22.06.00", "/sysadmin/installation/version_notes/v22.06.00", null ],