Summary
Bonded pairs or LAG (LACP) typically hash traffic per flow (5-tuple/Layer-3/4 policies), meaning a single TCP stream will live on one member link. To see the aggregate capacity (e.g., 2×25 G, 4×25 G), you must use multiple flows and/or multiple destinations.
Best-practice checklist
- Multiple parallel streams from the test client (iperf3
-P). - Multiple endpoints (IPs) when your hashing policy requires it.
- Sufficient duration (≥ 30–60 s).
Example commands (iperf3)
iperf3 -c <server> -t 60 -P 16
iperf3 -c <server> -t 60 -P 16 -R
iperf3 -c <server> -u -b 20G -t 60 -P 8
Reference Research & Guides
- ESnet / FasterData — 100G Benchmarking: shows examples of parallel streaming and how aggregating multiple flows is essential to reach near-line-rate. ESnet 100G Benchmarking
- ESnet / FasterData — Other tuning options that include flow classification, netdev parameters etc. which impact bonded/LAG behavior. Other Tuning Options
