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ILMT and Sub-Capacity

The ILMT to BigFix Migration Path

IBM Audit Journal · ILMT and Sub-Capacity · May 2026

HCL BigFix Inventory and IBM ILMT share a lineage, which makes BigFix one of the few IBM approved alternatives for sub-capacity reporting. Migrating is straightforward in theory, but the audit risk lives in the handover window, where one tool has stopped and the other has not yet produced a clean quarter.

Why the two tools are related

ILMT is built on the BigFix platform, and HCL BigFix Inventory is its commercial sibling. Both are accepted by IBM as approved sub-capacity measurement tools. Buyers move to BigFix Inventory for broader inventory features, to consolidate onto an existing BigFix estate, or to align with an HCL support arrangement.

What IBM still requires after you migrate

The tool changes; the obligations do not. The new tool must classify IBM products correctly, run continuously, generate quarterly reports, and you must retain two years of those reports. A tool swap does not reset the clock or forgive an earlier gap.

The handover window is the risk

Almost every migration problem we see traces back to the window where ownership of reporting was unclear. The failure modes are consistent.

A clean migration sequence

The safe path keeps both tools alive until the new one has proven itself.

Keep the evidence trail

Retention follows the data, not the tool. The ILMT reports you generated before the move still have to be available for two years, even after ILMT itself is decommissioned. Archive them where an auditor can be shown them, alongside the new BigFix reports.

What this means under audit

An auditor does not care which approved tool you use, only that an approved tool produced continuous, retained quarterly reports for every eligible product. A migration that leaves a single unreported quarter gives IBM a full-capacity claim for that period. Run the tools in parallel and never retire the old one until the new one has a clean quarter on record.

Related reading.

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Independent. Not affiliated with IBM Corporation.Buyer Side · Est. 2019