GH issues

Author: HeidiSteen

articles/search/search-reliability.md

@@ -24,14 +24,16 @@ For business continuity and recovery from disasters at a regional level, plan on
 
 ## High availability
 
-In Cognitive Search, replicas are copies of your index. A search service is installed with at least one replica, and can have up to 12 replicas. [Adding replicas](search-capacity-planning.md#adjust-capacity) allows Azure Cognitive Search to do machine reboots and maintenance against one replica, while query execution continues on other replicas.
+In Cognitive Search, replicas are copies of your index. A search service is commissioned with at least one replica, and can have up to 12 replicas. [Adding replicas](search-capacity-planning.md#adjust-capacity) allows Azure Cognitive Search to do machine reboots and maintenance against one replica, while query execution continues on other replicas.
 
 For each individual search service, Microsoft guarantees at least 99.9% availability for configurations that meet these criteria:
 
 + Two replicas for high availability of read-only workloads (queries)
 
 + Three or more replicas for high availability of read-write workloads (queries and indexing) 
 
+Internally, the system uses internal mechanisms to monitor replica health and partition integrity. If you provision a specific combination of replicas and partitions, the system ensures that level of capacity for your service.
+
 No SLA is provided for the Free tier. For more information, see [SLA for Azure Cognitive Search](https://azure.microsoft.com/support/legal/sla/search/v1_0/).
 
 <a name="availability-zones"></a>

articles/search/search-what-is-an-index.md

@@ -145,6 +145,8 @@ In Cognitive Search, you'll work with one index at a time, where all index-relat
 
 ### Continuously available
 
+An index is immediately available for queries as soon as the first document is indexed, but won't be fully operational until all documents are indexed. Internally, a search index is [distributed across partitions and executes on replicas](search-capacity-planning.md#concepts-search-units-replicas-partitions-shards). The physical index is managed internally. The logical index is managed by you.
+
 An index is continuously available, with no ability to pause or take it offline. Because it's designed for continuous operation, any updates to its content, or additions to the index itself, happen in real time. As a result, queries might temporarily return incomplete results if a request coincides with a document update.
 
 Notice that query continuity exists for document operations (refreshing or deleting) and for modifications that don't affect the existing structure and integrity of the current index (such as adding new fields). If you need to make structural updates (changing existing fields), those are typically managed using a drop-and-rebuild workflow in a development environment, or by creating a new version of the index on production service.