Cluster Autoscaler for ROSA HCP

Author: bmcelvee

_topic_maps/_topic_map_rosa.yml

@@ -607,6 +607,9 @@ Topics:
     File: dedicated-aws-dc
 - Name: Cluster autoscaling
   File: rosa-cluster-autoscaling
+- Name: Cluster autoscaling for ROSA HCP
+  File: rosa-cluster-autoscaling-hcp
+  # Remove cluster autoscaling for ROSA HCP once the HCP docs are published
 - Name: Manage nodes using machine pools
   Dir: rosa_nodes
   Distros: openshift-rosa

_topic_maps/_topic_map_rosa_hcp.yml

@@ -374,6 +374,8 @@ Topics:
     File: dedicated-aws-vpn
   - Name: Configuring AWS Direct Connect
     File: dedicated-aws-dc
+- Name: Cluster autoscaling
+  File: rosa-cluster-autoscaling
 - Name: Manage nodes using machine pools
   Dir: rosa_nodes
   Topics:

modules/cluster-autoscaler-about.adoc

@@ -5,28 +5,42 @@
 // * osd_cluster_admin/osd_nodes/osd-nodes-about-autoscaling-nodes.adoc
 // * osd_cluster_admin/osd-cluster-autoscaling.adoc
 // * rosa_cluster_admin/rosa-cluster-autoscaling.adoc
+// * rosa_cluster_admin/rosa-cluster-autoscaling-hcp.adoc (temporary)
+
 
 :_mod-docs-content-type: CONCEPT
 [id="cluster-autoscaler-about_{context}"]
 = About the cluster autoscaler
 
 The cluster autoscaler adjusts the size of an {product-title} cluster to meet its current deployment needs. It uses declarative, Kubernetes-style arguments to provide infrastructure management that does not rely on objects of a specific cloud provider. The cluster autoscaler has a cluster scope, and is not associated with a particular namespace.
+ifdef::openshift-rosa-hcp[]
+In {product-title}, the Cluster Autoscaler is fully managed, which means it is hosted along with the control plane.
+endif::openshift-rosa-hcp[]
+
 
 The cluster autoscaler increases the size of the cluster when there are pods that fail to schedule on any of the current worker nodes due to insufficient resources or when another node is necessary to meet deployment needs. The cluster autoscaler does not increase the cluster resources beyond the limits that you specify.
 
+ifdef::openshift-rosa-hcp[]
+The cluster autoscaler computes the total memory, CPU, and GPU only on the nodes that belong to autoscaling machine pools. All of the machine pool nodes that are not autoscaling are excluded from this aggregation. For example, if you set the `maxNodesTotal` to `50` on a {product-title} cluster with three machine pools in which a single machine pool is not autoscaling, the cluster autoscaler restricts the total nodes to `50` in only those two machine pools that are autoscaling. The single manually scaling machine pool can have additional nodes, making the overall cluster nodes total more than `50`.
+endif::openshift-rosa-hcp[]
+
+ifndef::openshift-rosa-hcp[]
 The cluster autoscaler computes the total
 ifndef::openshift-dedicated,openshift-rosa[]
 memory, CPU, and GPU
-endif::[]
+endif::openshift-dedicated,openshift-rosa[]
 ifdef::openshift-dedicated,openshift-rosa[]
 memory and CPU
-endif::[]
+endif::openshift-dedicated,openshift-rosa[]
 on all nodes the cluster, even though it does not manage the control plane nodes. These values are not single-machine oriented. They are an aggregation of all the resources in the entire cluster. For example, if you set the maximum memory resource limit, the cluster autoscaler includes all the nodes in the cluster when calculating the current memory usage. That calculation is then used to determine if the cluster autoscaler has the capacity to add more worker resources.
+endif::openshift-rosa-hcp[]
 
+ifndef::openshift-rosa-hcp[]
 [IMPORTANT]
 ====
 Ensure that the `maxNodesTotal` value in the `ClusterAutoscaler` resource definition that you create is large enough to account for the total possible number of machines in your cluster. This value must encompass the number of control plane machines and the possible number of compute machines that you might scale to.
 ====
+endif::openshift-rosa-hcp[]
 
 [discrete]
 [id="cluster-autoscaler-scale-down_{context}"]

modules/rosa-cluster-autoscaler-cli-after.adoc

@@ -6,24 +6,26 @@
 [id="rosa-enable-cluster-autoscale-cli-after_{context}"]
 = Enable autoscaling after cluster creation with the ROSA CLI
 
+////
 [IMPORTANT]
 ====
 The following procedure is only supported for ROSA Classic clusters. To enable autoscaling after cluster creation for ROSA with HCP clusters, see link:https://docs.openshift.com/rosa/rosa_cluster_admin/rosa_nodes/rosa-nodes-about-autoscaling-nodes.html#nodes-enabling-autoscaling-nodes[Enabling autoscaling nodes on a cluster].
 ====
+////
 
 You can use the ROSA CLI (`rosa`) to set cluster-wide autoscaling after cluster creation.
 
 .Procedure
-
-- After you have created a cluster, create the autoscaler:
+ 
+* After you have created a cluster, create the autoscaler:
 +
 .Example
 [source,terminal]
 ----
 $ rosa create autoscaler --cluster=<mycluster>
 ----
 +
-.. You can also create the autoscaler with specific parameters using the following command:
+** You can also create the autoscaler with specific parameters using the following command:
 +
 .Example
 [source,terminal]

modules/rosa-cluster-autoscaler-cli-delete.adoc

@@ -8,7 +8,9 @@
 
 You can delete the cluster autoscaler if you no longer want to use it.
 
-- To delete the cluster autoscaler, run the following command:
+.Procedure
+
+* To delete the cluster autoscaler, run the following command:
 +
 .Example
 [source,terminal]

modules/rosa-cluster-autoscaler-cli-describe.adoc

@@ -0,0 +1,35 @@
+// Module included in the following assemblies:
+//
+// * rosa_cluster_admin/rosa-cluster-autoscaling.adoc
+
+:_mod-docs-content-type: PROCEDURE
+[id="rosa-cluster-autoscaler-cli-describe_{context}"]
+= View autoscaler configurations with the ROSA CLI
+
+You can view your cluster autoscaler configurations using the `rosa describe autoscaler` command.
+
+//ROSA HCP procedure
+ifdef::openshift-rosa-hcp[]
+.Procedure
+
+* To view cluster autoscaler configurations, run the following command:
++
+.Example
+[source,terminal]
+----
+$ rosa describe autoscaler -h --cluster=<mycluster>
+----
+endif::openshift-rosa-hcp[]
+
+//ROSA Classic procedure
+ifdef::openshift-rosa[]
+.Procedure
+
+* To view cluster autoscaler configurations, run the following command:
++
+.Example
+[source,terminal]
+----
+$ rosa describe autoscaler --cluster=<mycluster>
+----
+endif::openshift-rosa[]

modules/rosa-cluster-autoscaler-cli-edit.adoc

@@ -8,18 +8,42 @@
 
 You can edit any specific parameters of the cluster autoscaler after creating the autoscaler.
 
-- To edit the cluster autoscaler, run the following command:
+.Procedure
+
+//ROSA HCP procedure
+ifdef::openshift-rosa-hcp[]
+* To edit the cluster autoscaler, run the following command:
++
+.Example
+[source,terminal]
+----
+$ rosa edit autoscaler -h --cluster=<mycluster>
+----
++
+** To edit a specific parameter, run the following command:
++
+.Example
+[source,terminal]
+----
+$ rosa edit autoscaler -h --cluster=<mycluster> <parameter>
+----
+endif::openshift-rosa-hcp[]
+
+//ROSA Classic procedure
+ifdef::openshift-rosa[]
+* To edit the cluster autoscaler, run the following command:
 +
 .Example
 [source,terminal]
 ----
 $ rosa edit autoscaler --cluster=<mycluster>
 ----
 +
-.. To edit a specific parameter, run the following command:
+** To edit a specific parameter, run the following command:
 +
 .Example
 [source,terminal]
 ----
 $ rosa edit autoscaler --cluster=<mycluster> <parameter>
 ----
+endif::openshift-rosa[]

modules/rosa-cluster-autoscaler-cli-settings.adoc

@@ -17,6 +17,8 @@ You can add the following parameters to the cluster creation command to configur
 |Type or Range
 |Example/Instruction
 
+ifdef::openshift-rosa[]
+//Classic only
 |`--autoscaler-balance-similar-node-groups`
 |Identify node groups with the same instance type and label set, and try to balance respective sizes of those node groups.
 |`boolean`
@@ -31,17 +33,22 @@ You can add the following parameters to the cluster creation command to configur
 |Autoscaler log level. Replace _int_ in the command with the number you want to use.
 |`integer`
 |`--autoscaler-log-verbosity 4`
+endif::openshift-rosa[]
 
+//Both Classic and HCP
 |`--autoscaler-max-pod-grace-period _int_`
 |Gives pods graceful termination time before scaling down, measured in seconds. Replace _int_ in the command with the number of seconds you want to use.
 |`integer`
 |`--autoscaler-max-pod-grace-period 0`
 
+//Both Classic and HCP
 |`--autoscaler-pod-priority-threshold _int_`
 |The priority that a pod must exceed to cause the cluster autoscaler to deploy additional nodes. Replace _int_ in the command with the number you want to use, can be negative.
 |`integer`
 |`--autoscaler-pod-priority-threshold -10`
 
+ifdef::openshift-rosa[]
+//Classic only
 |`--autoscaler-gpu-limit _stringArray_`
 |Minimum and maximum number of different GPUs in cluster. Cluster autoscaler does not scale the cluster less than or greater than these numbers. The format must be a comma-separated list of "<gpu_type>,<min>,<max>".
 |`array`
@@ -51,22 +58,30 @@ You can add the following parameters to the cluster creation command to configur
 |If set, the cluster-autoscaler ignores daemon set pods when calculating resource utilization for scaling down.
 |`boolean`
 |Add it to set to true, omit the option to set to false.
+endif::openshift-rosa[]
 
+//Both Classic and HCP
 |`--autoscaler-max-node-provision-time _string_`
 |Maximum time that the cluster autoscaler waits for a node to be provisioned. Replace _string_ in the command with an integer and time unit (ns,us,µs,ms,s,m,h).
 |`string`
 |`--autoscaler-max-node-provision-time 35m`
 
+ifdef::openshift-rosa[]
+//Classic only
 |`--autoscaler-balancing-ignored-labels _strings_`
 |A comma-separated list of label keys that the cluster autoscaler should ignore when comparing node groups for similarity. Replace _strings_ in the command with the relevant labels..
 |`string`
 |`--autoscaler-balancing-ignored-labels topology.ebs.csi.aws.com/zone,alpha.eksctl.io/instance-id`
+endif::openshift-rosa[]
 
+//Both Classic and HCP
 |`--autoscaler-max-nodes-total _int_`
 |Maximum amount of nodes in the cluster, including the autoscaled nodes. Replace _int_ in the command with the number you want to use.
 |`integer`
 |`--autoscaler-max-nodes-total 180`
 
+ifdef::openshift-rosa[]
+//Classic only
 |`--autoscaler-min-cores _int_`
 |Minimum number of cores to deploy in the cluster. Replace _int_ in the command with the number you want to use.
 |`integer`
@@ -116,5 +131,6 @@ You can add the following parameters to the cluster creation command to configur
 |How long after scale down failure that scale down evaluation resumes. Replace _string_ in the command with an integer and time unit (ns,us,µs,ms,s,m,h).
 |`string`
 |`--autoscaler-scale-down-delay-after-failure 1h`
+endif::openshift-rosa[]
 
 |===