Red Hat Enterprise Licensing and Host Affinity Rules

[Jonathan69]

Hi  community ! 

I have a use case here which I can't find a solution for. 

We have licenses for both RHEL Server and Virtual Data Center. On our clusters we have set Host Affinity rules to optimize licensing of cluster.  These affinity rules have been created by discovery in the cmdb_ci_cluster_vm_host_rule table and we have all the details needed.

Our problem is that they are not being leveraged at all during reconciliation. Reconciliation results logs do not show any steps that would be failing and the sys_property for com.snc.samp.oracle.hostaffinityenabled is enabled. 

My assumption is that, as the sys_property's description mentions reconciliation of RHEL does not take affinity rules into account at all. 

Would by any chance anyone have found a solution to this use case?  

Thank you in advance for your inputs.

Best Regards,

Jo

[MikeW0609686430]

Hi Jo - my understanding is that the reconciliation takes into account virtualisation density (number of hosts and VMs) and determines whether a RHEL VDC or Standard license is the best way of licensing the cluster.

There is a SAM property - Red Hat Enterprise Linux Server for Virtual Datacenters license cost optimization threshold - which can be changed to take into account any affinity rules.

[Jonathan69]

Hi Mike ! 

thank you for your answer but unfortunately that has nothing to do with affinity rules.

I know about that property but as far as I can see it is only about the threshold to determine, based on the ratio of the subscription price of Datacenter/server, which subscription is the most optimum to use ; 

"The default value for the Red Hat Enterprise Linux for Virtual Datacenters license cost optimization threshold field is 3.2. This value is based on the ratio of the current RHEL Server subscription list price to the current RHEL for Virtual Datacenters subscription list price. If your entitlements contain different pricings for these products, then you can calculate this value by dividing your RHEL for Virtual Datacenters subscription price by your RHEL Server subscription price."

Nothing in the documentation mentions anything about affinity rules....

br,

Jo

[MikeW0609686430]

I guess the question is - how do affinity rules impact Linux licensing? What outcome are you looking for following reconciliation?

[Jonathan69]

Hi Mike,

I hope you are doing well and thank you for your answer.

Yes or how to have affinity taken into account during the reconciliation. 

Let me set this in an example; For RHEL Vitrual Data center Licensing, if we have a cluster with 8 host running windows/linux vms but we have host affinity rules for linux, which limits the movements of Linux VMS to only 2 esx in the cluster; we only need to license the cluster with the amount of licenses necessary for these 2 hosts. not all 8.

esx1 - 2 Socket - Linux affinity rule

esx2 - 2 Socket - Linux affinity rule

esx3 - 2 Socket

esx4 - 2 Socket

esx5 - 2 Socket

esx6 - 2 Socket

esx7 - 2 Socket

esx8 - 2 Socket

At the moment reconciliation results conclude that we need to license 8 X 2 Sockets / 2 (Because license metric type is socket pair.) --> 8 Subscriptions to cover the cluster with RHEL Virtual DataCenter.

Actually, as we have these rules in place, we would only need 2 subcriptions to be compliant. 

Host affinity rules are, as far as I know supported by ServiceNow for VMWare, Oracle.... but I don't see any confirmation about Linux. 

I hope I managed to make it clearer 🙂

Best Regards,
Jo