Articles & Guides
Useful resources for web developers and system administrators
Found 46 · DNS · Reset
DNS
CNAME at the Apex: ALIAS, ANAME and Flattening at 8 DNS Hosts
Compare apex ALIAS, ANAME and CNAME flattening at 8 DNS hosts. Direct dig queries verify A and AAAA answers, mail records, and delegation before migration.
DNS
Domain status codes: clientHold, serverHold, pendingDelete
A practical guide to all 23 ICANN EPP status codes: holds, transfer locks, redemptionPeriod and pendingDelete, with RDAP examples and next actions.
DNS
dig Command Examples: 25 Tested DNS Troubleshooting Commands
25 tested dig commands: compare resolvers, query authoritative nameservers, trace delegation, and inspect DNSSEC. Real output shows what to check next.
DNS
nslookup Command: How to Use It and Read the Output
How to use nslookup on Windows, Linux and macOS: query a specific DNS server, look up MX, TXT, NS and SOA records, read the output and fix common errors.
DNS
DNS Server Not Responding: How to Fix It on Windows and More
DNS server not responding? Find the cause by symptom and fix it: router reboot, flushdns, Winsock reset, public DNS like 1.1.1.1, nslookup tests, macOS and Linux.
DNS
Cloudflare 1.1.1.1 IPv6 DNS: 2606:4700:4700::1111 and Setup
Cloudflare DNS: IPv4 1.1.1.1 and 1.0.0.1, IPv6 2606:4700:4700::1111 and ::1001, filtered 1.1.1.2 and 1.1.1.3, DoH and DoT. Setup and fixes.
DNS
AdGuard DNS Addresses: 94.140.14.14 Setup and What It Blocks
AdGuard DNS: 94.140.14.14 and 94.140.15.15 block ads and trackers, 94.140.14.15 is the family filter, 94.140.14.140 is unfiltered. DoH, DoT, DoQ.
DNS
Quad9 DNS 9.9.9.9: Addresses, Setup and Malware Blocking
Quad9 DNS: 9.9.9.9 and 149.112.112.112 block malicious domains, 9.9.9.10 is unfiltered, 9.9.9.11 adds ECS. IPv6, DoH and DoT setup, vs 1.1.1.1.
DNS
Ghost Domain: Why a Removed Delegation Still Resolves
A resolver learns your nameservers from two places, and the second one can refresh itself forever. That is why a nameserver migration can outlive its own TTL.
DNS
Resolvers Return Different IPs: Propagation and Stale Cache
Two resolvers, two answers for one hostname. Four causes, only one fixes itself. Query each authoritative nameserver and tell propagation from a real defect.