The Kalenfy blog

Security, in plain English

Guides on SPF · DMARC · DNSSEC & more — then scan your site free

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

27 June 2026

What Is CSRF (Cross-Site Request Forgery)?

CSRF tricks a logged-in user's browser into making a request they didn't intend — changing a password or making a payment. Here's how it works and how to prevent it, in plain English.

Read guide
Email authentication

27 June 2026

DKIM Selector Explained (And How to Find Yours)

A DKIM selector tells receivers which public key to use to verify your email. Here's what a selector is, how to find yours, and why it matters — with a free check of your domain.

Read guide
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.

Read guide
Guides & checklists

27 June 2026

What Is Cross-Site Scripting (XSS)?

Cross-site scripting (XSS) lets attackers run malicious scripts on your site, stealing data from your visitors. Here's how it works and how to prevent it, in plain English.

Read guide
Fixes & troubleshooting

27 June 2026

What Is DNS Propagation? (Why Changes Take Time)

Just changed a DNS record and nothing's happening? That's DNS propagation. Here's what it really is, how long it takes, why TTL matters, and how to check — with a free scan.

Read guide
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.

Read guide
Guides & checklists

27 June 2026

What Is Clickjacking? (And How to Stop It)

Clickjacking tricks your visitors into clicking something they can't see by hiding your site in an invisible frame. Here's how it works and how to block it. Free check included.

Read guide
Fixes & troubleshooting

27 June 2026

How to Redirect HTTP to HTTPS (Force HTTPS)

Stop the 'Not secure' warning by forcing every visitor onto HTTPS. Here's how to redirect HTTP to HTTPS on Apache, Nginx and Cloudflare — and lock it in with HSTS. Free check.

Read guide
Guides & checklists

27 June 2026

What Are HTTP Security Headers? (HSTS, CSP & More)

HTTP security headers tell browsers how to protect your visitors — blocking clickjacking, mixed content and more. Here's what each one does and how to add them. Free scan included.

Read guide
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.

Read guide
← NewerPage 3 / 6Older →