The DomainLedger blog

Plain guides on the things that break without anyone noticing: domains, certificates, business email and DNS. Written for whoever ends up responsible, which is usually not the person who set any of it up.

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Certificates

Certificates
My certificate chain is incomplete.
Certificates

My certificate chain is incomplete.

An incomplete chain works in your browser and fails for other people. How to spot it and how to fix it.

4 min read
Certificates
My certificate is expiring.
Certificates

My certificate is expiring.

Most certificates renew themselves. When one does not, the renewal job has usually stopped running somewhere nobody is looking.

4 min read
Certificates
My certificate is not trusted.
Certificates

My certificate is not trusted.

Visitors see a full-page warning before reaching your site. The four causes and what each one needs.

4 min read
Certificates
TLS certificate.
Certificates

TLS certificate.

Expiry, issuer, covered names and the full chain of trust, checked continuously and kept as a dated lineage.

4 min read
Certificates
Certificates renew themselves now, which created a new problem.
Certificates

Certificates renew themselves now, which created a new problem.

Automation removed most certificate failures and made the remaining ones harder to see.

4 min read
Certificates
My certificate expires soon. Is that a problem?
Certificates

My certificate expires soon. Is that a problem?

It depends on whether it renews automatically. If it does, the expiry is a symptom and the renewal job stopping is the actual prob…

4 min read
Certificates
What is a CAA record and do I need one?
Certificates

What is a CAA record and do I need one?

It lists which certificate authorities may issue certificates for your domain. Without one, any authority can, and most domains do…

4 min read

Business email

Business email
No DKIM signature was found.
Business email

No DKIM signature was found.

DKIM lets a receiving server verify a message really came from you. How to publish it and why keys stop matching.

4 min read
Business email
My DMARC is rejecting my own mail.
Business email

My DMARC is rejecting my own mail.

A strict policy plus an unauthorised sender means your own mail is being rejected on your own instructions.

4 min read
Business email
Anyone can send email pretending to be you.
Business email

Anyone can send email pretending to be you.

Without DMARC, receiving servers have no instruction about forged mail from your domain. How to publish it safely.

4 min read
Business email
My SPF record has too many lookups.
Business email

My SPF record has too many lookups.

SPF allows ten DNS lookups. Past that the whole record fails silently while still looking correct.

4 min read
Business email
There is no SPF record.
Business email

There is no SPF record.

Nothing tells receiving servers which systems may send mail for your domain. How to publish one that works.

4 min read
Business email
What breaks business email.
Business email

What breaks business email.

Mail failing produces no error on your side. Why quotes go unanswered, what actually breaks, and how to tell.

4 min read
Business email
Mail records.
Business email

Mail records.

We watch the records that decide whether your email arrives and whether it can be impersonated, and report in plain language.

4 min read
Business email
Do I need DMARC?
Business email

Do I need DMARC?

If your domain sends email, yes. Without it anyone can send mail claiming to be you, and receiving servers have no instruction abo…

4 min read
Business email
Why are my emails going to spam?
Business email

Why are my emails going to spam?

Usually authentication rather than content. If SPF, DKIM or DMARC is misconfigured, receiving servers filter you regardless of wha…

4 min read

Domains

Domains
My domain is expiring.
Domains

My domain is expiring.

Renew it, check the card on file has not expired, and move the notices somewhere that survives someone leaving.

5 min read
Domains
Transfer lock is off.
Domains

Transfer lock is off.

What the lock does, why it is off, and how to turn it on at your registrar.

4 min read
Domains
Why domains lapse, and what it costs to get one back.
Domains

Why domains lapse, and what it costs to get one back.

Renewal notices go to inboxes nobody reads and cards expire silently. What happens on the day a domain expires, the grace period, …

5 min read
Domains
Domain registration.
Domains

Domain registration.

We watch your renewal date, registrar, nameservers and transfer lock, and keep a dated record of every change.

4 min read
Domains
Why your registrar's renewal email is not a safety net.
Domains

Why your registrar's renewal email is not a safety net.

It arrives reliably. The problem is where it goes and what it assumes.

4 min read
Domains
The thirty days after a domain expires.
Domains

The thirty days after a domain expires.

What actually happens between expiry and release, and where the cost curve turns.

5 min read
Domains
Can someone take my domain if it expires?
Domains

Can someone take my domain if it expires?

Yes, once it is released. Before that there is a recovery window, and how long it lasts depends on your extension.

4 min read
Domains
How often should I check my domain?
Domains

How often should I check my domain?

More often than you will. That is the actual answer, and it is why this is worth automating rather than diarising.

4 min read
Domains
What does clientTransferProhibited mean?
Domains

What does clientTransferProhibited mean?

It means transfer lock is on, which is good. Your domain cannot be moved to another registrar without you unlocking it first.

4 min read

All 10 pages on domains

DNS and subdomains

DNS and subdomains
My staging site is public.
DNS and subdomains

My staging site is public.

How to check what is exposed, remove it from search results, and restrict it without breaking anyone's workflow.

4 min read
DNS and subdomains
A subdomain points at nothing.
DNS and subdomains

A subdomain points at nothing.

A record pointing at a cancelled service can be claimed by someone else. How to confirm it and remove it.

4 min read
DNS and subdomains
Records pointing nowhere.
DNS and subdomains

Records pointing nowhere.

A subdomain pointing at a deprovisioned service is a takeover risk. How it happens, why it matters and how to close it.

4 min read
DNS and subdomains
Hosting and pages.
DNS and subdomains

Hosting and pages.

Where your site actually lives, which third-party scripts are embedded, and what changed on the pages that matter.

3 min read
DNS and subdomains
Subdomains.
DNS and subdomains

Subdomains.

Everything still resolving under your domain, including forgotten staging sites and records pointing at services that no longer ex…

3 min read
DNS and subdomains
The staging site problem.
DNS and subdomains

The staging site problem.

Nearly every established domain has one, and nobody currently employed put it there.

5 min read
DNS and subdomains
What is the difference between my domain, my hosting and my DNS?
DNS and subdomains

What is the difference between my domain, my hosting and my DNS?

Three separate things, often at three different companies, and the confusion between them is why problems get investigated in the …

4 min read
DNS and subdomains
How long does DNS propagation take?
DNS and subdomains

How long does DNS propagation take?

Usually minutes, not the 24 to 48 hours people quote. That figure is a worst case from an era of much longer cache times.

4 min read
DNS and subdomains
What is a dangling DNS record?
DNS and subdomains

What is a dangling DNS record?

A record pointing at a service you no longer use. If that service releases the name, someone else can claim it and serve content f…

4 min read

All 10 pages on dns and subdomains

Records and evidence