Physical networks layout¶

This section summarizes the requirements for the physical layout of underlay network and VLANs configuration for the multi-rack architecture of Mirantis OpenStack for Kubernetes (MOSK).

Physical networking of a Container Cloud management cluster¶

Due to limitations of virtual IP address for Kubernetes API and of MetalLB load balancing in Container Cloud, the management cluster nodes must share VLAN segments in the provisioning and management networks.

In the multi-rack architecture, the management cluster nodes may be placed to a single rack or spread across three racks. In either case, provisioning and management network VLANs must be stretched across ToR switches of the racks.

The following diagram illustrates physical and L2 connections of the Container Cloud management cluster.

../../_images/os-cluster-mgmt-physical.png

Physical networking of a MOSK cluster¶

External network¶

Due to limitations of MetalLB load balancing, all MOSK cluster nodes must share the VLAN segment in the external network.

In the multi-rack architecture, the external network VLAN must be stretched to the ToR switches of all racks. All other VLANs may be configured per rack.

Kubernetes manager nodes¶

Due to limitations of using a virtual IP address for Kubernetes API, the Kubernetes manager nodes must share the VLAN segment in the API/LCM network.

In the multi-rack architecture, Kubernetes manager nodes may be spread across three racks. The API/LCM network VLAN must be stretched to the ToR switches of the racks. All other VLANs may be configured per rack.

The following diagram illustrates physical and L2 network connections of the Kubernetes manager nodes in a MOSK cluster.

Caution

Such configuration does not apply to a compact control plane MOSK installation. See Create a MOSK cluster.

../../_images/os-cluster-k8s-mgr-physical.png

OpenStack controller nodes¶

The following diagram illustrates physical and L2 network connections of the control plane nodes in a MOSK cluster.

../../_images/os-cluster-control-physical.png

OpenStack compute nodes¶

All VLANs for OpenStack compute nodes may be configured per rack. No VLAN should be stretched across multiple racks.

The following diagram illustrates physical and L2 network connections of the compute nodes in a MOSK cluster.

../../_images/os-cluster-compute-physical.png

OpenStack storage nodes¶

All VLANs for OpenStack storage nodes may be configured per rack. No VLAN should be stretched across multiple racks.

The following diagram illustrates physical and L2 network connections of the storage nodes in a MOSK cluster.

../../_images/os-cluster-storage-physical.png