Kubernetes Internal Management Network PlanningΒΆ

The internal management network is a private network, visible only to the hosts in the cluster.

Note

This network is not used with StarlingX Simplex systems.

You must consider the following guidelines:

  • The internal management network is used for PXE booting of new hosts, and must be untagged. It is limited to IPv4, because the StarlingX installer does not support IPv6 PXE booting. For example, if the internal management network needs to be on a VLAN-tagged network for deployment reasons, or if it must support IPv6, you can configure the optional untagged PXE boot network for PXE booting of new hosts using IPv4.

  • You can use any 1 GB or 10 GB interface on the hosts to connect to this network, provided that the interface supports network booting and can be configured from the BIOS as the primary boot device.

  • If static IP address assignment is used, you must use the system host-add command to add new hosts, and to assign IP addresses manually. In this mode, new hosts are not automatically added to the inventory when they are powered on, and they display the following message on the host console:

    This system has been configured with static management
and infrastructure IP address allocation. This requires
that the node be manually provisioned in System
Inventory using the 'system host-add' CLI, GUI, or
stx API equivalent.

  • For the IPv4 address plan, use a private IPv4 subnet as specified in RFC 1918. This helps prevent unwanted cross-network traffic on this network.

    It is suggested that you use the default subnet and addresses provided by the controller configuration script.

  • You can assign a range of addresses on the management subnet for use by the StarlingX. If you do not assign a range, StarlingX takes ownership of all available addresses.

  • On systems with two controllers, they use IP multicast messaging on the internal management network. To prevent loss of controller synchronization, ensure that the switches and other devices on these networks are configured with appropriate settings.