Add comment clarifying network allocation and sizes (kubernetes-sigs#…

…6607) * Add comment from roles/kubespray-defaults/defaults/main.yaml clarifying network allocation and sizes Signed-off-by: Mikael Johansson <[email protected]> * Rewrite of the comment and added new examples Signed-off-by: Mikael Johansson <[email protected]>
southbridgeio · Jan 16, 2021 · fb2298b · fb2298b
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diff --git a/inventory/sample/group_vars/k8s-cluster/k8s-cluster.yml b/inventory/sample/group_vars/k8s-cluster/k8s-cluster.yml
@@ -95,8 +95,20 @@ kube_service_addresses: 10.233.0.0/18
 kube_pods_subnet: 10.233.64.0/18
 
 # internal network node size allocation (optional). This is the size allocated
-# to each node on your network.  With these defaults you should have
-# room for 4096 nodes with 254 pods per node.
+# to each node for pod IP address allocation. Note that the number of pods per node is
+# also limited by the kubelet_max_pods variable which defaults to 110.
+#
+# Example:
+# Up to 64 nodes and up to 254 or kubelet_max_pods (the lowest of the two) pods per node:
+#  - kube_pods_subnet: 10.233.64.0/18
+#  - kube_network_node_prefix: 24
+#  - kubelet_max_pods: 110
+#
+# Example:
+# Up to 128 nodes and up to 126 or kubelet_max_pods (the lowest of the two) pods per node:
+#  - kube_pods_subnet: 10.233.64.0/18
+#  - kube_network_node_prefix: 25
+#  - kubelet_max_pods: 110
 kube_network_node_prefix: 24
 
 # The port the API Server will be listening on.

diff --git a/roles/kubespray-defaults/defaults/main/main.yaml b/roles/kubespray-defaults/defaults/main/main.yaml
@@ -175,16 +175,20 @@ kube_service_addresses: 10.233.0.0/18
 kube_pods_subnet: 10.233.64.0/18
 
 # internal network node size allocation (optional). This is the size allocated
-# to each node on your network.  With these defaults you should have
-# room for 64 nodes with 254 pods per node.
-# Example: Up to 256 nodes, 100 pods per node (/16 network):
-#  - kube_service_addresses: 10.233.0.0/17
-#  - kube_pods_subnet: 10.233.128.0/17
-#  - kube_network_node_prefix: 25
-# Example: Up to 4096 nodes, 100 pods per node (/12 network):
-#  - kube_service_addresses: 10.192.0.0/13
-#  - kube_pods_subnet: 10.200.0.0/13
+# to each node for pod IP address allocation. Note that the number of pods per node is
+# also limited by the kubelet_max_pods variable which defaults to 110.
+#
+# Example:
+# Up to 64 nodes and up to 254 or kubelet_max_pods (the lowest of the two) pods per node:
+#  - kube_pods_subnet: 10.233.64.0/18
+#  - kube_network_node_prefix: 24
+#  - kubelet_max_pods: 110
+#
+# Example:
+# Up to 128 nodes and up to 126 or kubelet_max_pods (the lowest of the two) pods per node:
+#  - kube_pods_subnet: 10.233.64.0/18
 #  - kube_network_node_prefix: 25
+#  - kubelet_max_pods: 110
 kube_network_node_prefix: 24
 
 # The virtual cluster IP, real host IPs and ports the API Server will be