how to determine cluster network mac address

With the introduction of the new admission controller, the first (unpopulated scenario) will be evaluated differently: We check if that desired address is already allocated and block the request.

In such case, the CNI assigns the specified address. In such case, the CNI assigns a MAC address.Ī static MAC address is present. There are 2 possibilities for the 'mac' field: In order to control the allocation of MAC addresses for network devices, the admission controller will intercept the initialization of a Pod and observe its NetworkAttachmentDefinition's 'mac' field. A user will be able to pass their own desired range, or let a default range take place. The admission controller will operate within a predefined address range. Designīoth the act of modifying a Pod's template and deriving available addresses will be done by a new designated admission controller. This specification will describe how the allocation process (as described in collision prevention section) will ensure no collisions may occur. For convenience sake, I will only refer to Pods throughout this document. It is also to be noted that besides Pods, the proposed behavior will be generic enough to support future entities that may require MAC address allocation.

During this step, a Pod's template will be read, processed, and modified to specify a MAC address. This specification will describe an intermediate step prior to the initialization of Pods within a kubernetes cluster. This document proposes a collision-free allocation of MAC addresses within a single cluster. The cluster must have multus installed and configured. LimitationsĬNI plugins that do not implement CNI's MAC address specification will not be supported. Many CNI plugins allocate MAC addresses randomly, with no assurance of collision prevention.Įven if a CNI plugin ensures it never creates collisions, a cluster operating with multiple CNI plugins or sharing a broadcast domain with another cluster will remain collision-prone. Kubernetes MAC pool address allocation MotivationĪs of date, there is no way to ensure MAC address collisions do not occur within a Kubernetes cluster.

How to determine cluster network mac address