Null-only measurements are omitted during InfluxDB 1.x-to-2.x bucket migration

Null-only measurements are omitted during InfluxDB 1.x-to-2.x bucket migration

The influxd-upgrade utility converts InfluxDB 1.x line protocol data into the 2.x bucket model. During this conversion, any data point where every field value is null is omitted from the target bucket. The behavior is documented in the 1.x-to-2.x migration guidance, and no configuration flag is available in current 2.x releases to alter it; operators should confirm the exact behavior against their target version.

This creates a compatibility boundary for teams that rely on null-only points to represent intentional gaps or to drive downstream sample-count calculations. Because the tool logs dropped null points only when logging is set to info or higher, a default or lower verbosity run may not surface the loss. Whether null-only points should be preserved remains an open design question in the project, so the long-term direction is unresolved.

Before committing to an upgrade path, operators must decide whether to pre-clean the 1.x data, reinsert null points manually after migration, or accept the resulting cardinality reduction. The choice depends on whether the affected series carry semantic meaning beyond their null values.

What is the recommended approach for preserving intentionally null measurements when running influxd-upgrade in current 2.x releases? Does the tool expose any logging or dry-run mechanism to reliably identify all null-only series before the actual migration? Are there documented plans to add a configuration option that retains null-only points in future 2.x versions?