Merge pull request #1563 from redis/DOC-5233

RC: Active-Active Limitations and High Availability changes

Author: cmilesb

content/operate/rc/databases/configuration/active-active-redis.md

@@ -19,6 +19,10 @@ Active-Active databases allow read and write operations in each copy.  Each copy
 
 When developing for Active-Active databases, you need to consider some important differences. See [Develop applications with Active-Active databases]({{< relref "/operate/rs/databases/active-active/develop/_index.md" >}}) for related information.
 
+    {{< note >}}
+Active-Active subscriptions on Redis Cloud are limited to a maximum of 10 regions and 10 databases.
+    {{< /note >}}
+
 ## Active-Active geo-distributed replication highlights
 
 ### Multi-zone

content/operate/rc/databases/configuration/high-availability.md

@@ -34,7 +34,10 @@ Your replication options depend on your [subscription plan]({{< relref "/operate
 - Free Redis Cloud Essentials plans do not support replication.
 - Paid Redis Cloud Essentials plans and Redis Cloud Pro plans let you choose between multi-zone or single-zone replication when creating a subscription. You can also turn off replication.
 
-After database creation, you can still enable or turn off replication.  However, [zone settings]({{< relref "/operate/rc/databases/configuration/high-availability#zone-setting-maintenance" >}}) are only configurable during database creation.  
+Whether or not you can change your replication settings after database creation depends on your plan type and what type of replication you originally selected.
+
+- For Redis Cloud Essentials, you select the kind of replication when you create your database. If you selected Multi-zone replication when you created your database, you can't change it to Single-zone or turn it off after database creation. However, if you selected No Replication or Single-zone replication, you can switch between the two at any time by [editing your Essentials subscription]({{< relref "/operate/rc/subscriptions/view-essentials-subscription#change-high-availability-and-persistence" >}}). 
+- For Redis Cloud Pro, you select whether you want a multi-zone deployment during subscription creation. You can't change this setting or any [Zone settings]({{< relref "/operate/rc/databases/configuration/high-availability#zone-setting-maintenance" >}}) after subscription creation. However, you can activate or deactivate replication for each database within the subscription at any time by [editing your database]({{< relref "/operate/rc/databases/view-edit-database" >}}).
 
 ## Performance impact 
 

content/operate/rc/databases/create-database/create-active-active-database.md

@@ -31,7 +31,7 @@ Redis Cloud maintains consistency among instances in the background; that is, ea
     {{<image filename="images/rc/create-database-subscription-pro-new.png" alt="The Subscription selection panel with Pro selected.">}}
 
     {{< note >}}
-This guide shows how to create an Active-Active database with a new Pro subscription. If you already have an Active-Active subscription and want to add a database to it, see [Create a Pro database in an existing subscription]({{< relref "/operate/rc/databases/create-database/create-pro-database-existing" >}}). 
+This guide shows how to create an Active-Active database with a new Pro subscription. If you already have an Active-Active subscription and want to add a database to it, see [Create a Pro database in an existing subscription]({{< relref "/operate/rc/databases/create-database/create-pro-database-existing" >}}). Active-Active subscriptions can host a maximum of 10 databases.
     {{< /note >}}
 
 
@@ -70,6 +70,10 @@ When you enable Active-Active Redis, two regions are selected by default. Select
 
 {{<image filename="images/rc/create-sub-active-active-regions.png" width="50%" alt="Use the Region drop-down to select the regions for your Active-Active database." >}}
 
+    {{< note >}}
+Active-Active subscriptions on Redis Cloud are limited to a maximum of 10 regions.
+    {{< /note >}}
+
 Use the checkboxes in the list to select or remove regions.  The Search box lets you locate specific regions.
 
 You can use a region's Remove button to remove it from the list.