Number inventory reconciliation: the unglamorous work that makes migrations work

This article is a draft in preparation. The outline reflects the topics we intend to cover; the full text is being written.

On large migrations, the number inventory is where data problems surface first. CUCM, Webex Calling, and carrier records almost never agree, and manual reconciliation does not scale past a few thousand DIDs.

This article will describe the reconciliation workflow we use — extracting from each system of record, normalizing, matching, and flagging exceptions — and how Python and Webex API tooling turn it from a weeks-long manual effort into a repeatable process.

We will also cover how reconciled inventory feeds directly into API-driven provisioning and porting coordination.