Where congestion comes from
Growth and bursts: backups, replication, and AI training bursts crush links sized for average load. Failover shifts: a failed link pushes traffic onto survivors — congestion caused by lost redundancy. Incast: many sources respond to one destination at the same time. Small uplinks: the access layer grew but the uplink did not keep up.
Congestion or hardware? The counters know
From the user's side they look identical — the fix is the opposite. Congestion shows up as high utilization, queue drops, and latency that rises with load. Hardware problems show up as CRC errors and packet loss independent of load. Key advantages: per-link utilization baselines, queue drops and CRC errors shown separately, saturation alerts before users notice, and congestion triggered by failed redundancy flagged explicitly.
FAQ
Network congestion is when traffic demand exceeds link or device capacity. It can be caused by undersized uplinks, traffic bursts, broadcast storms, or a failed link pushing traffic onto survivors. To tell congestion from a hardware problem: check interface counters at both ends of the suspect link — a few minutes usually settles it.