Recent Blog Posts
Tuning Unbound DNS for High-Throughput Linux Workloads
Optimize Unbound DNS resolver performance with thread pinning, SO_REUSEPORT, aggressive NSEC caching, and memory tuning on production Linux.
Tuning PowerDNS with LMDB Backend for High QPS
Optimize PowerDNS Authoritative Server using the LMDB backend. Step-by-step performance tuning for high query volume and minimal latency.
Zero-Downtime Enterprise DNS Migrations: Overcoming NS Caching
Master enterprise DNS migrations without downtime. Learn parent-zone NS caching mechanics, TTL step-down workflows, and dual-provider cutover strategies.
Debugging Strict SPF, DKIM, and DMARC Syntax
Resolve email deliverability drops caused by strict SPF/DKIM alignment mismatches, void lookups, and DMARC syntax evaluation bugs.
Zero-Downtime Enterprise DNS Migration and TLD Delegation
Master enterprise DNS migrations without downtime. Learn parent zone TTL mechanics, NS delegation sync, and registrar cutover strategies.
Debugging SPF, DKIM, and DMARC Syntax Failures
Diagnose and resolve SPF lookup limits, DKIM base64 string splitting issues, and DMARC alignment failures across production DNS zones.
Fixing SPF PermError and DKIM Syntax Parsing Failures
Debug and resolve SPF 10-lookup PermError limits, DKIM 2048-bit key chunking errors, and DMARC strict alignment failures with precise DNS configurations.
Fixing BIND9 TSIG Zone Transfer Failures & REFUSED Errors
Troubleshoot and fix BIND9 secondary zone AXFR/IXFR transfer failures caused by TSIG signature verification errors, algorithm mismatches, and clock skew.
Fix PowerDNS AXFR TSIG and Autoprimary NOTIFY Errors
Resolve PowerDNS zone transfer failures, TSIG BADSIG validation errors, and rejected NOTIFY packets from primary nameservers with production SQL fixes.