OSDOCS-18425# Add hyperdisk-balanced high availability support

Author: Lisa Pettyjohn

modules/persistent-storage-csi-gcp-hyperdisk-ha-overview.adoc

@@ -0,0 +1,22 @@
+// Module included in the following assemblies:
+//
+// * storage/container_storage_interface/persistent-storage-csi-gcp-pd.adoc
+
+:_mod-docs-content-type: CONCEPT
+[id="persistent-storage-csi-gcp-hyperdisk-ha-overview_{context}"]
+= Hyperdisk-balanced high availability disks overview
+
+[role="_abstract"]
+{product-title} supports Hyperdisk Balanced High Availability volumes.
+
+Hyperdisk Balanced High Availability volumes are useful for:
+
+* Protecting your applications from a zonal outage by synchronously replicating data across two zones in the same region
+
+* When you require write access to the same volume in multiple zones
+
+For a single Hyperdisk Balanced High Availability volume, you can specify up to 100,000 IOPS and 1,200 MiB/s of throughput.
+
+To set up Hyperdisk Balanced High Availability disks, see Section _Setting up hyperdisk-balanced disks_.
+
+For complete limit information, in the _Additional resources_ section, see _Size and performance limits_.

modules/persistent-storage-csi-gcp-hyperdisk-storage-pools-procedure.adoc

@@ -155,7 +155,7 @@ allowedTopologies: <7>
 ----
 <1> Specify the name for your storage class. In this example, it is `hyperdisk-sc`.
 <2> `pd.csi.storage.gke.io` specifies GCP CSI provisioner.
-<3> Specifies using hyperdisk-balanced disks.
+<3> Specifies using hyperdisk-balanced disks. To specify high availability hyperdisk-balanced disk, set the value to `hyperdisk-balanced-high-availability`. 
 <4> Specifies the throughput value in MiBps using the "Mi" qualifier. For example, if your required throughput is 250 MiBps, specify "250Mi". If you do not specify a value, the capacity is based upon the disk type default.
 <5> Specifies the IOPS value without any qualifiers. For example, if you require 7,000 IOPS, specify "7000". If you do not specify a value, the capacity is based upon the disk type default.
 <6> If using storage pools, specify a list of specific storage pools that you want to use in the format: projects/PROJECT_ID/zones/ZONE/storagePools/STORAGE_POOL_NAME.

storage/container_storage_interface/persistent-storage-csi-gcp-pd.adoc

@@ -42,6 +42,8 @@ include::modules/persistent-storage-csi-gcp-pd-storage-class-ref.adoc[leveloffse
 
 include::modules/persistent-storage-csi-gcp-hyperdisk-limitations.adoc[leveloffset=+2]
 
+include::modules/persistent-storage-csi-gcp-hyperdisk-ha-overview.adoc[leveloffset=+2]
+
 include::modules/persistent-storage-csi-gcp-hyperdisk-storage-pools-overview.adoc[leveloffset=+2]
 
 To set up storage pools, see xref:../../storage/container_storage_interface/persistent-storage-csi-gcp-pd.adoc#persistent-storage-csi-gcp-hyperdisk-storage-pools-procedure_persistent-storage-csi-gcp-pd[Setting up hyperdisk-balanced disks].
@@ -53,6 +55,8 @@ ifndef::openshift-dedicated[]
 [role="_additional-resources"]
 === Additional resources
 * xref:../../installing/installing_gcp/installing-gcp-customizations.adoc#installing-gcp-customizations[Installing a cluster on GCP with customizations]
+
+* link:https://docs.cloud.google.com/compute/docs/disks/hd-types/hyperdisk-balanced-ha#size_limits[Size and performance limits]
 endif::openshift-dedicated[]
 
 include::modules/persistent-storage-csi-gcp-pd-encrypted-pv.adoc[leveloffset=+1]