Author Archives: Alex Hofsteede

Diagnosing networking issues in the Linux Kernel

A few weeks ago we started noticing a dramatic change in the pattern of network traffic hitting our tracking API servers in Washington DC. From a fairly stable daily pattern, we started seeing spikes of 300-400 Mbps, but our rate of legitimate traffic (events and people updates) was unchanged.

Suddenly our network traffic started spiking like crazy.

Pinning down the source of this spurious traffic was a top priority, as some of these spikes were triggering our upstream routers into a DDos mitigation mode, where traffic was being throttled.

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