docs: Update installation docs (#1226)

# Description

Minor changes applied to update the installation documentation.

## Checklist

- [X] I have read the [contributing
documentation](https://retina.sh/docs/contributing).
- [X] I signed and signed-off the commits (`git commit -S -s ...`). See
[this
documentation](https://docs.github.com/en/authentication/managing-commit-signature-verification/about-commit-signature-verification)
on signing commits.
- [X] I have correctly attributed the author(s) of the code.
- [X] I have tested the changes locally.
- [X] I have followed the project's style guidelines.
- [X] I have updated the documentation, if necessary.
- [ ] I have added tests, if applicable.

---

Please refer to the [CONTRIBUTING.md](../CONTRIBUTING.md) file for more
information on how to contribute to this project.

docs/02-Installation/01-Setup.md

@@ -6,7 +6,9 @@ Note: you can also run captures with just the [CLI](./02-CLI.md).
 
 ## Installation
 
-Requires Helm version >= v3.8.0.
+### Requirements
+
+- Helm version >= v3.8.0.
 
 ### Basic Mode
 

docs/02-Installation/03-Config.md

@@ -2,25 +2,60 @@
 
 ## Overview
 
-To customize metrics and other options, modify the `retina-config` ConfigMap. Default settings for each component are specified in *deploy/legacy/manifests/controller/helm/retina/values.yaml*.
+### Default Configuration
 
-## Agent Config
+Default settings for each component are specified in [Values file](../../deploy/legacy/manifests/controller/helm/retina/values.yaml).
+
+### Deployed Configuration
+
+Configuration of an active Retina deployment can be seen in `retina-config` and `retina-operator-config` configmaps.
+
+```shell
+kubectl get configmap retina-config -n kube-system -o yaml
+kubectl get configmap retina-operator-config -n kube-system -o yaml
+```
+
+### Updating Configuration
+
+If the Retina installation was done via Helm, configuration updates should be done via `helm upgrade` defining the specific attribute name and value as part of the command.
+
+The example below enables gathering of advance pod-level metrics.
+
+```shell
+VERSION=$( curl -sL https://api.github.com/repos/microsoft/retina/releases/latest | jq -r .name)
+helm upgrade --install retina oci://ghcr.io/microsoft/retina/charts/retina \
+    --version $VERSION \
+    --namespace kube-system \
+    --set image.tag=$VERSION \
+    --set operator.tag=$VERSION \
+    --set logLevel=info \
+    --set enabledPlugin_linux="\[dropreason\,packetforward\,linuxutil\,dns\]"
+    --set enablePodLevel=true
+```
+
+## General Configuration
+
+Apply to both Agent and Operator.
 
 * `enableTelemetry`: Enables telemetry for the agent for managed AKS clusters. Requires `buildinfo.ApplicationInsightsID` to be set if enabled.
-* `enablePodLevel`: Enables gathering of advanced pod-level metrics, attaching pods' metadata to Retina's metrics.
 * `remoteContext`: Enables Retina to watch Pods on the cluster.
-* `enableAnnotations`: Enables gathering of metrics for annotated resources. Resources can be annotated with `retina.sh=observe`. Requires the operator and `enableRetinaEndpoint` to be enabled.
-* `enabledPlugin`: List of enabled plugins.
+
+## Agent Configuration
+
+* `logLevel`: Define the level of logs to store.
+* `enabledPlugin_linux`: List of enabled plugins.
 * `metricsInterval`: Interval for gathering metrics (in seconds). (@deprecated, use `metricsIntervalDuration` instead)
 * `metricsIntervalDuration`: Interval for gathering metrics (in `time.Duration`).
+* `enablePodLevel`: Enables gathering of advanced pod-level metrics, attaching pods' metadata to Retina's metrics.
+* `enableConntrackMetrics`: Enables conntrack metrics for packets and bytes forwarded/received.
+* `enableAnnotations`: Enables gathering of metrics for annotated resources. Resources can be annotated with `retina.sh=observe`. Requires the operator and `operator.enableRetinaEndpoint` to be enabled.
 * `bypassLookupIPOfInterest`: If true, plugins like `packetparser` and `dropreason` will bypass IP lookup, generating an event for each packet regardless. `enableAnnotations` will not work if this is true.
 * `dataAggregationLevel`: Defines the level of data aggregation for Retina. See [Data Aggregation](../05-Concepts/data-aggregation.md) for more details.
 
-## Operator Config
+## Operator Configuration
 
-* `installCRDs`: Allows the operator to manage the installation of Retina-related CRDs.
-* `enableTelemetry`: Enables telemetry for the operator in managed AKS clusters. Requires `buildinfo.ApplicationInsightsID` to be set if enabled.
-* `captureDebug`: Toggles debug mode for captures. If true, the operator uses the image from the test container registry for the capture workload. Refer to *pkg/capture/utils/capture_image.go* for details on how the debug capture image version is selected.
-* `captureJobNumLimit`: Sets the maximum number of jobs that can be created for each Capture.
-* `enableRetinaEndpoint`: Allows the operator to monitor and update the cache with Pod metadata.
-* `enableManagedStorageAccount`: Enables the use of a managed storage account for storing artifacts.
+* `operator.installCRDs`: Allows the operator to manage the installation of Retina-related CRDs.
+* `operator.enableRetinaEndpoint`: Allows the operator to monitor and update the cache with Pod metadata.
+* `capture.captureDebug`: Toggles debug mode for captures. If true, the operator uses the image from the test container registry for the capture workload. Refer to [Capture Image file](../../pkg/capture/utils/capture_image.go) for details on how the debug capture image version is selected.
+* `capture.captureJobNumLimit`: Sets the maximum number of jobs that can be created for each Capture.
+* `capture.enableManagedStorageAccount`: Enables the use of a managed storage account for storing artifacts.

docs/02-Installation/04-prometheus.md

@@ -6,6 +6,7 @@ Prometheus is an open-source system monitoring and alerting toolkit originally b
 
 1. Create a Kubernetes cluster.
 2. Install Retina DaemonSet (see [Quick Installation](./01-Setup.md)).
+3. Clone [Retina Repository](https://github.com/microsoft/retina) or download [Prometheus Values File](../../deploy/legacy/prometheus/values.yaml).
 
 ## Install Prometheus via Helm
 
@@ -19,13 +20,17 @@ Prometheus is an open-source system monitoring and alerting toolkit originally b
 1. Install the Prometheus chart
 
   ```shell
-  helm install prometheus -n kube-system -f deploy/legacy/prometheus/values.yaml prometheus-community/kube-prometheus-stack
+  # The value of VALUE_FILE_PATH is relative to the repo root folder. Update this according to the location of your file.
+  VALUE_FILE_PATH=deploy/legacy/prometheus/values.yaml
+  helm install prometheus -n kube-system -f $VALUE_FILE_PATH prometheus-community/kube-prometheus-stack
   ```
 
   Or if you already have the chart installed, upgrade how you see fit, providing the new job name as an additional scrape config, ex:
 
   ```shell
-  helm upgrade prometheus -n kube-system -f deploy/legacy/prometheus/values.yaml prometheus-community/kube-prometheus-stack
+  # The value of VALUE_FILE_PATH is relative to the repo root folder. Update this according to the location of your file.
+  VALUE_FILE_PATH=deploy/legacy/prometheus/values.yaml
+  helm upgrade prometheus -n kube-system -f $VALUE_FILE_PATH prometheus-community/kube-prometheus-stack
   ```
 
 > Note: Grafana and kube-state metrics may schedule on Windows nodes, the current chart doesn't have node affinity for those components. Some manual intervention may be required.