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DNS Lookup
Run a live DNS lookup for any domain. Domain Doctor resolves your A and AAAA records and checks that your domain points to valid, public addresses.
VASTROX HOSTING · EMAIL · DNS · SSL
Want VASTROX to fix every issue above — for you?
Don't fix it alone. Our team configures your SPF, DKIM, DMARC, SSL, DNS and security headers correctly, then hosts you on fast NVMe infrastructure so your domain scores an A and stays there.
- Every failing check fixed and verified
- Hosting, business email, DNS & SSL under one roof
- Free migration from your current provider
What this checks
DNS is the address book of the internet. Your A record maps your domain to an IPv4 address and your AAAA record to IPv6. If these are missing, wrong, or point to a private IP, your site is unreachable.
Domain Doctor queries your records live, confirms they resolve to routable public addresses, detects wildcard DNS, and distinguishes an unregistered domain (NXDOMAIN) from one that resolves but has no address record.
Common DNS Lookup errors
- Apex domain has no A record (only www is set up)
- A record pointing to an old host after migration
- Record pointing to a private IP (10.x, 192.168.x)
- Missing AAAA record for IPv6 visitors
- Unintended wildcard resolving every subdomain
VASTROX DNS & HOSTING
Rock-solid DNS managed by VASTROX
We host your DNS on redundant nameservers with correct records and DNSSEC, so your site and mail never drop.
- Redundant, fast nameservers
- Correct A / AAAA / MX / TXT records
- DNSSEC available
Trusted by businesses for hosting, VPS, business email & game servers · Free migration · Real support
Frequently asked questions
What is the difference between A and AAAA records?
An A record maps your domain to an IPv4 address; an AAAA record maps it to an IPv6 address. Ideally you publish both.
Why does www work but my bare domain doesn’t?
Your apex (@) is probably missing an A record. Add one pointing to your server, or set up a redirect from the apex to www.