Open-Source Tool Sentinel DNS Auto-Tunes Unbound Config Based on Server Hardware

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A developer built an open-source appliance called Sentinel DNS to eliminate the need for manual tuning of Unbound DNS servers at scale. The tool runs a boot script that reads system hardware details from /proc/cpuinfo and /proc/meminfo to dynamically generate optimal Unbound configurations. Parameters such as cache size, record-set cache, and thread count are automatically recalculated based on available CPU cores and RAM, whether on a small VM or a large bare-metal server. The appliance also addresses cache loss during reboots by dumping the Unbound cache to NVMe storage on shutdown and reloading it at startup, keeping resolution latency near zero. The project targets high-demand environments like ISPs and large corporate networks where default Unbound settings struggle under loads of 10,000 or more queries per second.

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