Line Protocol Bulk Import

Import InfluxDB Line Protocol files into Arc. Enables one-command migration from InfluxDB by uploading .lp or .txt files (plain or gzip-compressed).

Available since v26.02.1

Line Protocol bulk import is available starting Arc v26.02.1 (February 2026).

Streaming vs. Bulk

This page covers bulk file import via POST /api/v1/import/lp. For streaming ingestion of Line Protocol data (real-time writes), see the Line Protocol write endpoints in the API Reference.

Endpoint

POST /api/v1/import/lp

Headers

Header	Required	Default	Description
Authorization	Yes	-	Bearer $ARC_TOKEN
X-Arc-Database	Yes	-	Target database name (or use db query param)

Query Parameters

Parameter	Required	Default	Description
measurement	No	(all)	Filter to a single measurement from the LP file
precision	No	ns	Timestamp precision: ns, us, ms, s

Basic Example

curl -X POST "http://localhost:8000/api/v1/import/lp" \
  -H "Authorization: Bearer $ARC_TOKEN" \
  -H "X-Arc-Database: mydb" \
  -F "file=@export.lp"

Example with Precision

# Import LP file with second-precision timestamps
curl -X POST "http://localhost:8000/api/v1/import/lp?precision=s" \
  -H "Authorization: Bearer $ARC_TOKEN" \
  -H "X-Arc-Database: mydb" \
  -F "file=@export_seconds.lp"

Response

{
  "status": "ok",
  "result": {
    "database": "mydb",
    "measurements": ["cpu", "mem", "disk"],
    "rows_imported": 150000,
    "precision": "ns",
    "duration_ms": 342
  }
}

InfluxDB Migration

Export from InfluxDB and import directly into Arc. For InfluxDB 1.x, use influx_inspect export (the influx CLI does not support Line Protocol output):

# Export from InfluxDB 1.x (reads TSM and WAL directly)
influx_inspect export \
  -datadir /var/lib/influxdb/data \
  -waldir /var/lib/influxdb/wal \
  -database mydb -lponly -out export.lp

# Import to Arc
curl -X POST "http://localhost:8000/api/v1/import/lp" \
  -H "X-Arc-Database: mydb" \
  -H "Authorization: Bearer $ARC_TOKEN" \
  -F "file=@export.lp"

Multi-field measurements

influx_inspect export writes one Line Protocol line per field, so a multi-field point becomes several rows in Arc, each with one field populated. For multi-field measurements, use tsm2arc, which rejoins fields into a single point. See the full InfluxDB migration guide.

How It Works

Data flows through Arc's high-performance columnar ingest pipeline (ArrowBuffer -> ArrowWriter -> Parquet -> storage) -- the same path used by streaming LP ingestion. This means bulk imports benefit from the same throughput, sort optimization, and hourly partitioning.

Notes

• Multi-measurement -- a single LP file can contain multiple measurements; all are imported in one request.
• Precision-aware -- timestamps are losslessly converted from the specified precision to Arc's internal microsecond format.
• Gzip support -- compressed files (.lp.gz) are automatically detected and decompressed via magic bytes.
• RBAC -- write permissions are checked for every measurement in the file.
• Maximum file size: 500 MB (after decompression).

Error Responses

Status	Description
400	Missing database, invalid precision, or no file uploaded
403	Insufficient write permissions for one or more measurements
413	File exceeds 500 MB size limit
500	Import execution error