fixup! Add documentation for installing the recording server

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>

recording/docs/installation.md

@@ -1,10 +1,24 @@
 # Installation
 
+The recording server requires an HPB (High Performance Backend for Talk) to be setup. However, it is recommended to setup the recording server in a different machine than the HPB to prevent their load to interfere with each other. Moreover, as the recording server requires some dependencies that are not typically found in server machines, like Firefox, it is recommended to use its own "isolated" machine (either a real machine or a virtual machine). A container would also work, although it might require a special configuration to start the server when the container is started.
+
+In practice the recording server acts just as another Talk client, so it could be located anywhere as long as it can connect to the Nextcloud server and to the HPB, in the later case either directly or through the TURN server. Nevertheless, for simplicity and reliability, it is recommended for the recording server to have direct access to the HPB (so if the HPB is running in an internal network the recording server should be setup in that same internal network as the HPB).
+
+## Hardware requirements
+
+As a quick reference, with the default settings, in an AMD Ryzen 7 3700X 8-Core Processor (so 16 threads, theoretically a maximum usage of 1600% CPU) recording a single call uses 200% CPU (mostly to encode the video). The recording server provides [a benchmark tool](encoders.md) that can be used to check the load with different encoding settings and find out an approximation of the load that will occur when recording a call. Nevertheless in a real recording there is an additional load from the WebRTC connections, the rendering of the browser and so on, but in general the encoding uses the most CPU.
+
+Regarding RAM memory the encoding does not use much, and it should be calculated based on how many simultaneous recordings and therefore browsers are expected. For a single browser 2 GiB should be enough, although it would be recommended to play safe and have more if possible due to the increasing memory requirements of browsers (and also if the calls to be recorded include a lot of participants).
+
+Finally disk size will also depend on the number of simultaneous recordings, as well as the quality and codec used, which directly affect the size of the recording. In general the recorded videos will stay on the recording server only while being recorded and they will be removed as soon as they are uploaded to the Nextcloud server. However, if the upload fails the recorded video will be kept in the recording server until manually removed.
+
+## Installation type
+
 The recording server can be installed using system packages in some GNU/Linux distributions. A "manual" installation is required for others.
 
 In both cases the master branch of the [Nextcloud Talk repository](https://github.com/nextcloud/spreed) should be cloned. Currently the recording server in the master branch is backwards compatible with previous Talk releases, and the stable branches do not receive bug fixes for the recording server, as the latest version from the master branch is expected to be used.
 
-## System packages
+### System packages
 
 Distribution packages are supported for the following GNU/Linux distributions:
 - Debian 11
@@ -15,11 +29,11 @@ They can be built on those distributions by calling `make` in the _recording/pac
 
 The built packages can be found in _recording/packaging/build/{DISTRIBUTION-ID}/{PACKAGE-FORMAT}/_ (even if they were built inside the Docker containers using `build.sh`). They include the recording server itself (_nextcloud-talk-recording_) as well as the Python3 dependencies that are not included in the repositories of the distributions. Note that the built dependencies change depending on the distribution type and version.
 
-### Prerequisites
+#### Prerequisites
 
 Once built the packages can be installed using the package managers of the distributions, although some distributions have additional requirements that need to be fulfilled first.
 
-#### Debian 11
+##### Debian 11
 
 In Debian 11 there is no _geckodriver_ package, which is required to control Firefox from the recording server. Therefore the [PPA from Mozilla](https://launchpad.net/~mozillateam/+archive/ubuntu/ppa) needs to be setup instead before installing the packages. Although `add-apt-repository` is available in Debian 11 the PPA does not provide packages for _bullseye_, so the PPA needs to be manually added to use the packages for _focal_ (Ubuntu 20.04):
 ```
@@ -36,7 +50,7 @@ Pin-Priority: 1001
 ' | sudo tee /etc/apt/preferences.d/mozilla-firefox
 ```
 
-#### Ubuntu 22.04
+##### Ubuntu 22.04
 
 In Ubuntu 22.04 the normal Firefox package was replaced by a Snap. Unfortunately the Snap package can not be used with the default packages, so the [PPA from Mozilla](https://launchpad.net/~mozillateam/+archive/ubuntu/ppa) needs to be setup instead before installing the packages (`add-apt-repository` is included in the package `software-properties-common`):
 ```
@@ -52,7 +66,7 @@ Pin-Priority: 1001
 ' | sudo tee /etc/apt/preferences.d/mozilla-firefox
 ```
 
-### Built packages installation
+#### Built packages installation
 
 In Debian and Ubuntu the built packages can be installed by first changing to the _recording/packaging/build/{DISTRIBUTION-ID}/deb/_ directory and then running:
 ```
@@ -65,7 +79,7 @@ Besides installing the recording server and its dependencies a _nextcloud-talk-r
 
 Although it is possible to configure the recording server to use Chromium/Chrome instead of Firefox only Firefox is officially supported, so only Firefox is a dependency of the `nextcloud-talk-recording` package. In order to use Chromium/Chrome it needs to be manually installed.
 
-## Manual installation
+### Manual installation
 
 The recording server has the following non-Python dependencies:
 - FFmpeg
@@ -90,17 +104,7 @@ You might want to configure a systemd service (or any equivalent service) to aut
 
 ## System setup
 
-It is recommended to setup the recording server in a different machine than the HPB (High Performance Backend for Talk) to prevent their load to interfere with each other. Moreover, as the recording server requires some dependencies that are not typically found in server machines, like Firefox, it is recommended to use its own "isolated" machine (either a real machine or a virtual machine). A container would also work, although it might require a special configuration to start the server when the container is started.
-
-In practice the recording server acts just as another Talk client, so it could be located anywhere as long as it can connect to the Nextcloud server and to the HPB, in the later case either directly or through the TURN server. Nevertheless, for simplicity and reliability, it is recommended for the recording server to have direct access to the HPB (so if the HPB is running in an internal network the recording server should be setup in that same internal network as the HPB).
-
-### Hardware requirements
-
-As a quick reference, with the default settings, in an AMD Ryzen 7 3700X 8-Core Processor (so 16 threads, theoretically a maximum usage of 1600% CPU) recording a single call uses 200% CPU (mostly to encode the video). The recording server provides [a benchmark tool](encoders.md) that can be used to check the load with different encoding settings and find out an approximation of the load that will occur when recording a call. Nevertheless in a real recording there is an additional load from the WebRTC connections, the rendering of the browser and so on, but in general the encoding uses the most CPU.
-
-Regarding RAM memory the encoding does not use much, and it should be calculated based on how many simultaneous recordings and therefore browsers are expected. For a single browser 2 GiB should be enough, although it would be recommended to play safe and have more if possible due to the increasing memory requirements of browsers (and also if the calls to be recorded include a lot of participants).
-
-Finally disk size will also depend on the number of simultaneous recordings, as well as the quality and codec used, which directly affect the size of the recording. In general the recorded videos will stay on the recording server only while being recorded and they will be removed as soon as they are uploaded to the Nextcloud server. However, if the upload fails the recorded video will be kept in the recording server until manually removed.
+Independently of how it was installed the recording server needs to be configured. Depending on the setup additional components like a firewall might also need to be setup or adjusted.
 
 ### Recording server configuration