OLS-4815: edits from QA review

Author: rh-tokeefe

modules/ossm-about-istio-high-availability.adoc

@@ -5,7 +5,7 @@
 [id="ossm-about-istio-high-availability_{context}"]
 = About Istio High Availability
 
-Running the {istio} control plane in High Availability (HA) mode prevents single points of failure, and ensures continuous mesh operation even if an `istiod` pod fails. By using HA, if one `istiod` pod becomes unavailable, another one continues to manage and configure the {istio} control plane, preventing service outages or disruptions. HA provides scalability by distributing the control plane workload, enables graceful upgrades, supports disaster recovery operations, and protects against zone-wide mesh outages.
+Running the {istio} control plane in High Availability (HA) mode prevents single points of failure, and ensures continuous mesh operation even if an `istiod` pod fails. By using HA, if one `istiod` pod becomes unavailable, another one continues to manage and configure the {istio} data plane, preventing service outages or disruptions. HA provides scalability by distributing the control plane workload, enables graceful upgrades, supports disaster recovery operations, and protects against zone-wide mesh outages.
 
 There are two ways for a system administrator to configure HA for the {istio} deployment:
 

modules/ossm-api-settings-mesh-ha-autoscaling.adoc

@@ -14,14 +14,14 @@ Use the following `istio` custom resource definition (CRD) parameters when you c
 
 |`autoScaleMin` | Defines the minimum number of `istiod` pods for an istio deployment. Each pod contains one instance of the Istio control plane. 
 
-{ocp-short-name} only uses this parameter when the {istio} deployment uses the Horizontal Pod Autoscaler (HPA) configuration. 
+{ocp-short-name} only uses this parameter when the Horizontal Pod Autoscaler (HPA) is enabled for the {istio} deployment. This is the default behavior.
 |`autoScaleMax` | Defines the maximum   number of `istiod` pods for an {istio} deployment. Each pod contains one instance of the {istio} control plane.
 
 For {ocp-short-name} to automatically scale the number of `istiod` pods based on load, you must set this parameter to a value that is greater than the value that you defined for the `autoScaleMin` parameter. 
 
 You must also configure metrics for autoscaling to work properly. If no metrics are configured, the autoscaler does not scale up or down.
 
-{ocp-short-name} only uses this parameter when the {istio} deployment uses the HPA configuration. 
+{ocp-short-name} only uses this parameter when Horizontal Pod Autoscaler (HPA) is enabled for the {istio} deployment. This is the default behavior.
 |`cpu.targetAverageUtilization` | Defines the target CPU utilization for the `istiod` pod. If the average CPU usage exceeds the threshold that this parameter defines, the HPA automatically increases the number of replica pods.
 |`memory.targetAverageUtilization` | Defines the target memory utilization for the `istiod` pod. If the average memory usage exceeds the threshold that this parameter defines, the HPA automatically increases the number of replica pods.
 |`behavior` | You can use the `behavior` field to define additional policies that {ocp-short-name} uses to scale {istio} resources up or down.