SPF record checker
SPF checker: read a domain’s SPF record, list its mechanisms и count the DNS lookups against the limit 10.
от Queries go до от Cloudflare’s public DNS over HTTPS service when you press the button. Up до от 15 queries are made до follow include records.
О «SPF record checker»
SPF checker: read a domain’s SPF record, list its mechanisms и count the DNS lookups against the limit 10.
Часть раздела «Данные и сети» SmartCalcy. Работает в вашем браузере без аккаунта, использует вашу валюту и единицы (меняются вверху страницы) и даёт оценки только для информации, поэтому перед тем как полагаться на результат, сверьтесь с официальными рекомендациями.
Как пользоваться: SPF record checker
Что считает и когда использовать
Reads a domain’s SPF record, the list от servers allowed до send email за it, и checks it за common faults: more than one record, a missing “all” policy, и от more than 10 DNS lookups, which makes SPF fail. It follows include records до count the lookups.
Как пользоваться, шаг за шагом
- Enter the domain, за Пример Пример.com.
- Press “Check SPF”.
- Read the verdict и the number DNS lookups used out 10.
- Review the mechanisms list и any warnings.
Что означает каждое поле
- Domain Название – The domain used в the sender’s address.
Как читать результаты
- Verdict – Looks valid, или Needs attention when a problem — found.
- Policy – от What happens до mail from servers that are not listed: hard fail, soft fail, neutral или allow.
- DNS lookups – Lookups needed by include, a, mx, ptr, exists и redirect terms, compared with the limit 10.
- Mechanisms – Every Срок в the record, with included records indented beneath their parent.
Формула
The record — the TXT value starting v=spf1. Each include, a, mx, ptr, exists или redirect term costs one DNS lookup, и included records add their own. ip4 и ip6 terms и “all” cost none. The RFC limit — 10 lookups.
Пример расчёта
v=spf1 include:_spf.Пример.net a mx -all uses three lookups за its own terms plus those inside the included record, и ends в -all, so unlisted servers are rejected.
Допущения и ограничения
- По most 15 queries are made while following includes, и nesting stops after 5 levels.
- A domain may need a record only за mail it sends. Domains that send Нет mail should publish v=spf1 -all.
- The check does not test whether a particular server would pass.
Частые ошибки
- Publishing two SPF records. Only one — allowed, so merge them into one.
- Ending with +all, which lets anyone send as your domain.
- Adding every email service as an include и passing 10 lookups, which обороты SPF into a permanent error.
Частые вопросы
What — SPF?
Sender Policy Framework — от a DNS record that lists the servers allowed до send email за a domain.
What — the difference between -all и ~all?
от -all asks receivers до от reject unlisted senders. ~all asks them до accept but mark the mail as suspicious.
Why — there a limit 10 lookups?
It stops a record С forcing receivers into long chains DNS queries. Going over it makes SPF return a permanent error.
от Is SPF enough до stop spoofing?
Нет. Use it with DKIM и DMARC.
Does this tool send email?
Нет. It only reads DNS records.