Compare your IBM sub capacity and full capacity PVUs, and the exposure if ILMT is not compliant. The readiness check and the moves.
IBM lets you license PVU products on sub capacity, paying for the cores actually running the product, but only if ILMT is deployed and scanning correctly. Without compliant ILMT, IBM can demand full capacity across every physical core.
Check the gap, then hold sub capacity.
Quick answer
IBM sub capacity licensing requires ILMT scanning at least every 30 minutes with two years of reports, and without it IBM can bill full capacity across every physical core, often 2 to 4 times more. Example: 200 physical cores with 50 running IBM products at 70 PVU each is 3,500 sub capacity PVUs versus 14,000 full capacity. See IBM License Metric Tool and IBM terms.
ILMT sub capacity readiness
IBM sub capacity licensing requires ILMT scanning at least every 30 minutes with two years of reports, and without it IBM can bill full capacity across every physical core, often 2 to 4 times more.
Sub capacity requires ILMT installed, scanning at least every thirty minutes, with reports retained for two years. Miss the requirement and IBM reverts you to full capacity.
Sub capacity licenses the cores running the product. Full capacity licenses every physical core in the environment. The gap is the exposure.
Each core carries a PVU value by processor type. The PVU per core, times cores, sets the license quantity.
Most exposure comes from lapsed scans or unmanaged hosts. Scan discipline is the compliance lever.
IBM audits sub capacity claims first. A clean ILMT record is the defense.
| Basis | Licenses | Requires |
|---|---|---|
| Sub capacity | Cores running the product | Compliant ILMT scanning |
| Full capacity | Every physical core | No ILMT, the default penalty |
The standard advice is that ILMT is an IT housekeeping task. We disagree. ILMT is a commercial control worth multiples of license cost. A lapsed scan can convert a sub capacity estate into a full capacity demand overnight. The buyer side move is to treat ILMT compliance as a board level cost control, not an afterthought, and to keep the two year scan record audit ready at all times.
Most ELAs do not break even on the second term. The buyer recommitted at a deployment forecast that overshot actual use. Model the true up eighteen months out, not at the anniversary letter, and the renewal reshapes itself.
It lets you license PVU products on the cores actually running the product, rather than every physical core, provided ILMT is deployed and scanning correctly.
IBM License Metric Tool must be installed, scan at least every thirty minutes, and retain reports for two years. Miss this and IBM can revert you to full capacity.
It depends on the estate, but full capacity bills every physical core and commonly runs two to four times the sub capacity figure. The check quantifies your gap.
It is directional, applying a PVU per core value to your inputs. Your processor types and contract set the final number.
Lapsed scans and unmanaged hosts. Scan discipline across the whole estate is the core control.
Yes. It is free and runs in your browser. No payment and no account required.
No. It is buyer side data. Use it to hold sub capacity and prepare the audit defense internally.
We review the ILMT deployment, quantify the full capacity exposure, build the audit defense, and sit at the table. We are not an IBM partner.
Tool output is the anchor. Walk into the IBM meeting with a PVU number you trust and the negotiation reshapes itself.
A buyer side reference on the IBM estate: PVU entitlement, ILMT sub capacity, ELA true ups, and Red Hat after the acquisition. Deployment math and renewal leverage.
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