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DNS & domain security

All our dns & domain security guides

All Email authentication DNS & domain security Fixes & troubleshooting Guides & checklists
DNS & domain security

27 June 2026

What Is DNS Cache Poisoning?

DNS cache poisoning tricks a resolver into storing a fake answer, sending users to an attacker's server. Here's how the attack works and how DNSSEC defends your domain against it.

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DNS & domain security

27 June 2026

What Is a CNAME Record? (DNS Aliases Explained)

A CNAME record points one hostname at another, like an alias. Here's what CNAME records do, the rules and gotchas, how they're used for DKIM and verification, and the takeover risk to avoid.

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DNS & domain security

27 June 2026

What Is Reverse DNS (PTR Record)?

Reverse DNS (a PTR record) maps a sending IP back to a hostname. Mail servers check it, and a missing or generic PTR sends your email to spam. Here's what it is and how to fix it.

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DNS & domain security

27 June 2026

What Is a Nameserver? (And Where to Edit DNS)

Confused about nameservers and where to actually change your DNS records? Here's what a nameserver is, how registrar, DNS host and web host differ, and how to find yours. Free check.

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DNS & domain security

27 June 2026

What Is Typosquatting? (Look-Alike Domains)

Typosquatting is when attackers register look-alike versions of your domain to fool your customers and staff. Here's how it works, why it's used in phishing and BEC, and how to defend.

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DNS & domain security

27 June 2026

What Is a TXT Record? (And Why It Matters)

A TXT record stores text in your DNS — and it's where SPF, DKIM and DMARC live. Here's what TXT records are, how to add them, and common mistakes to avoid. Free check included.

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DNS & domain security

27 June 2026

What Is a Subdomain? (And How to Keep It Secure)

A subdomain is a prefix on your domain like blog.example.com or shop.example.com. Here's what subdomains are, how they work, and the security risks to watch — with a free check.

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DNS & domain security

27 June 2026

How to Check Your DNS Records (Free & Easy)

Want to see your domain's DNS records — SPF, DMARC, MX and more? Here's how to check them three ways, what each should look like, and how to spot problems. Free scan included.

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DNS & domain security

27 June 2026

What Is an MX Record? (Email Routing Explained)

An MX record tells the world where to deliver email for your domain. Here's how MX records and their priorities work, common mistakes, and how to check yours free.

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DNS & domain security

27 June 2026

DNS Records Explained: A, CNAME, MX, TXT & More

A plain-English guide to DNS records — A, AAAA, CNAME, MX, TXT, NS and the security ones (CAA, DNSSEC). What each does, with a free scan to check your domain's setup.

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