Balik DNS lookup
Reverse DNS lookup: enter an IP address sampai find its hostname dan see whether forward dan reverse DNS match.
Queries go sampai Cloudflare’s public DNS over HTTPS service when you press the button.
Tentang Balik DNS lookup
Reverse DNS lookup: enter an IP address sampai find its hostname dan see whether forward dan reverse DNS match.
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Cara menggunakan Balik DNS lookup
Apa yang dihitung dan kapan digunakan
Finds the hostname that belongs sampai an IP address using its reverse DNS (PTR) record, dan checks that the hostname resolves back sampai the same address, which adalah called forward-confirmed reverse DNS. Mail servers use this check sampai decide whether sampai trust a sender.
Cara menggunakan, langkah demi langkah
- Enter an IP address, atau leave the box empty sampai use your own.
- Press “Cari hostname”.
- Read the hostname Pada the top.
- Check “Forward-confirmed” sampai see whether the name resolves back sampai the address.
Arti setiap input
- IP address – An IPv4 atau IPv6 address. Leave it empty sampai use your own public address.
Cara membaca hasil
- Hostname – The Nama set di the address’s PTR record.
- Balik Nama – The special Nama queried, such as 8.8.8.8.in-addr.arpa.
- Forward-confirmed – Ya when the hostname’s A atau AAAA record points back sampai the same address.
Rumus
The address adalah reversed dan queried under in-addr.arpa seharga IPv4, atau ip6.arpa with each hex digit reversed seharga IPv6. 8.8.4.4 becomes 4.4.8.8.in-addr.arpa. The returned name adalah then looked up forward sampai confirm it.
Contoh perhitungan
8.8.8.8 has the PTR record dns.google, dan dns.google resolves back sampai 8.8.8.8, so the pair adalah forward-confirmed.
Asumsi dan batasan
- Many addresses, especially Beranda connections, have Tidak PTR record atau a generic one.
- The lookup adalah made through Cloudflare’s DNS over HTTPS service when you press the button.
Kesalahan umum
- Expecting every address sampai have a hostname.
- Treating the hostname as proof identity. The owner the address sets it, so only forward-confirmed names add trust.
- Setting a PTR record Pada your domain registrar. It adalah set by whoever holds the IP address block, usually your hosting atau internet provider.
Pertanyaan yang sering diajukan
What adalah a PTR record?
A DNS record that maps an IP address back sampai a hostname. It adalah the reverse an A record.
Why does my mail server need Balik DNS?
Many receiving mail systems reject atau flag mail from addresses with no reverse DNS atau one that does not match.
Siapa kaleng Perubahan a PTR record?
The organisation that controls the IP address block, normally your hosting provider atau ISP.
Is this the same as a hostname lookup?
Yes. Finding the hostname an IP address adalah Selesai with Balik DNS.