PProxySmartinproxysmart.hashnode.dev·Aug 17 · 7 min readDNS Troubleshooting That Scales: Reading A, AAAA, CNAME, MX, TXT, NS, and TTLDNS incidents often look random from the application layer: one user reaches the new server, another reaches the old one, email stops arriving, or a certificate check fails only in one region. The fas00
PProxySmartinproxysmart.hashnode.dev·Aug 13 · 7 min readBuilding a Production-Grade Proxy Health Check in Node.jsA proxy that accepts a TCP connection is not necessarily healthy. It may return the wrong exit IP, resolve DNS locally, take too long to reach the target, or fail only under concurrency. For productio00
