Merge pull request #28680 from mburke5678/logging-volumeMode-block

Do not use volumeMode: block in LocalVolume object

Author: mburke5678

modules/cluster-logging-deploy-cli.adoc

@@ -12,6 +12,11 @@ You can use the {product-title} CLI to install the Elasticsearch and Cluster Log
 * Ensure that you have the necessary persistent storage for Elasticsearch. Note that each Elasticsearch node
 requires its own storage volume.
 +
+[NOTE]
+====
+If you use a local volume for persistent storage, do not use a raw block volume, which is described with `volumeMode: block` in the `LocalVolume` object. Elasticsearch cannot use raw block volumes.
+====
++
 Elasticsearch is a memory-intensive application. By default, {product-title} installs three Elasticsearch nodes with memory requests and limits of 16 GB. This initial set of three {product-title} nodes might not have enough memory to run Elasticsearch within your cluster. If you experience memory issues that are related to Elasticsearch, add more Elasticsearch nodes to your cluster rather than increasing the memory on existing nodes.
 
 ifdef::openshift-origin[]

modules/cluster-logging-deploy-console.adoc

@@ -12,14 +12,19 @@ You can use the {product-title} web console to install the Elasticsearch and Clu
 * Ensure that you have the necessary persistent storage for Elasticsearch. Note that each Elasticsearch node
 requires its own storage volume.
 +
+[NOTE]
+====
+If you use a local volume for persistent storage, do not use a raw block volume, which is described with `volumeMode: block` in the `LocalVolume` object. Elasticsearch cannot use raw block volumes.
+====
++
 Elasticsearch is a memory-intensive application. By default, {product-title} installs three Elasticsearch nodes with memory requests and limits of 16 GB. This initial set of three {product-title} nodes might not have enough memory to run Elasticsearch within your cluster. If you experience memory issues that are related to Elasticsearch, add more Elasticsearch nodes to your cluster rather than increasing the memory on existing nodes.
 
 ifdef::openshift-origin[]
 * Ensure that you have downloaded the link:https://cloud.redhat.com/openshift/install/pull-secret[pull secret from the Red Hat OpenShift Cluster Manager site] as shown in _Obtaining the installation program_ in the installation documentation for your platform.
 +
 If you have the pull secret, add the `redhat-operators` catalog to the OperatorHub custom resource (CR) as shown in _Configuring {product-title} to use Red Hat Operators_.
 endif::[]
-
+ 
 .Procedure
 
 To install the Elasticsearch Operator and Cluster Logging Operator using the {product-title} web console:

modules/cluster-logging-deploy-storage-considerations.adoc

@@ -11,6 +11,11 @@ An Elasticsearch index is a collection of primary shards and their corresponding
 
 A persistent volume is required for each Elasticsearch deployment configuration. On {product-title} this is achieved using persistent volume claims.
 
+[NOTE]
+====
+If you use a local volume for persistent storage, do not use a raw block volume, which is described with `volumeMode: block` in the `LocalVolume` object. Elasticsearch cannot use raw block volumes.
+====
+
 The Elasticsearch Operator names the PVCs using the Elasticsearch resource name.
 
 ////

modules/cluster-logging-elasticsearch-storage.adoc

@@ -43,3 +43,8 @@ metadata:
 ----
 
 This example specifies each data node in the cluster is bound to a Persistent Volume Claim that requests "200G" of AWS General Purpose SSD (gp2) storage.
+
+[NOTE]
+====
+If you use a local volume for persistent storage, do not use a raw block volume, which is described with `volumeMode: block` in the `LocalVolume` object. Elasticsearch cannot use raw block volumes.
+====

modules/persistent-storage-local-create-cr.adoc

@@ -20,7 +20,6 @@ Local volumes cannot be created by dynamic provisioning. Instead, persistent vol
 ====
 Do not use different storage class names for the same device. Doing so will create multiple persistent volumes (PVs).
 ====
-
 +
 .Example: Filesystem
 [source,yaml]
@@ -55,6 +54,11 @@ spec:
 <6> The path containing a list of local storage devices to choose from.
 <7> Replace this value with your actual local disks filepath to the `LocalVolume` resource, such as `/dev/xvdg`. PVs are created for these local disks when the provisioner is deployed successfully.
 +
+[NOTE]
+====
+A raw block volume (`volumeMode: block`) is not formatted with a file system. You should use this mode only if any application running on the pod can use raw block devices.
+====
++
 .Example: Block
 [source,yaml]
 ----

monitoring/configuring-the-monitoring-stack.adoc

@@ -84,6 +84,11 @@ See xref:../scalability_and_performance/optimizing-storage.adoc#recommended-conf
 * Use the block type of storage.
 
 * xref:../storage/persistent_storage/persistent-storage-local.adoc#persistent-storage-using-local-volume[Configure local persistent storage.]
++
+[NOTE]
+====
+If you use a local volume for persistent storage, do not use a raw block volume, which is described with `volumeMode: block` in the `LocalVolume` object. Elasticsearch cannot use raw block volumes.
+====
 
 include::modules/monitoring-configuring-a-local-persistent-volume-claim.adoc[leveloffset=+2]
 include::modules/monitoring-modifying-retention-time-for-prometheus-metrics-data.adoc[leveloffset=+2]