How to license IBM software in containers (kubernetes)?

IBM recently announced new rules for the licensing of IBM software in containers. To understand the methodology, the following definitions are important.

The goal ist to measure the “vCPU capacity”.

1. Each container has a CPU limit. At first, the CPU limit of all containers within a Pod will be added, resulting in the “vCPU limit of the pod”.
2. Then the “vCPU limit of the pod” will be multiplied with the number of Pods in the Cluster. Fractional values will be rounded up the next whole number.
3. If the result is bigger the physical capacity of the server (number if cores), it will be capped at that number.

An example:

1. We have 6 Pods running on a server with 12 cores. In each Pod 12 Containers are running, each with a CPU Limit of 0,3. The “vCPU limit of the pod” is counted as follows: 12 * 0,3 = 3,6
2. Now we determine the “vCPU Capacity”. 6 (Pods) * 3,6 (vCPU limit of the pod) = 21,6 Cores (which are rounded up to 22) Since the result if bigger than the physical capacity of the server, it is capped at 12 cores.

To determine the “vCPU capacity” in containers you have to use the IBM License Service Tool which does not replace the IBM License Metric Tool. If you do not use the tool, all the core in the cluster must be licensed.

Sources:

IBM Website about container licensing (https://www.ibm.com/software/passportadvantage/containerlicenses.html), retrieved 2020-10-26 IBM FAQ Website abut container (https://www.ibm.com/software/passportadvantage/containerfaqov.html), retrieved 2020-10-26