Table of Contents

Introduction Domain structure Rules for DNS naming Implementation notes Conclusion

Custom domain name policy

23. February 2025

Table of Contents

Introduction Domain structure Rules for DNS naming Implementation notes Conclusion

Introduction

This document outlines the rules and guidelines for configuring custom domain names in FotoWeb SaaS. Understanding the allowed configurations and limitations is essential to ensuring compliance with DNS naming standards.

Domain structure

Our system currently supports up to four levels in domain names. A typical domain name structure is represented as:

{FourthLevelDomain}.{ThirdLevelDomain}.{SecondLevelDomain}.{TopLevelDomain}

Examples:

service.department.company.com

department.company.com

company.com

Rules for DNS naming

Allowed configurations

Character types

Use alphanumeric characters (A-Z, a-z, 0-9) without spaces.

Hyphens (-) are permitted but cannot be placed at the beginning or end of any domain segment.

Length restrictions

Each subdomain (segment of the domain before a dot) can have up to 63 characters.

The entire domain name can have a maximum of 253 characters, including dots separating the domain levels.

Case sensitivity Domain names are not case-sensitive. Both uppercase and lowercase letters are treated equally.

Prohibited configurations

Special characters
Whitespace	Spaces or any form of whitespace characters are not allowed in domain names.
Numerical restrictions	Entirely numerical top-level domains (TLDs) are not permitted, although numbers can appear in other parts of the domain name.
Position of hyphens	Do not use leading or trailing hyphens in any part of the domain. Hyphens should not be placed in the third and fourth positions of any domain name segment.
TLD usage	A top-level domain (TLD) cannot be replicated as a second-level domain. For example, `.com.com` is invalid.

Implementation notes

The current system architecture supports up to four-level domains.
Validation routines must enforce the new policies to prevent configuration errors and ensure DNS compatibility.

Conclusion

Adhering to these domain name configuration rules ensures that our SaaS platform remains compliant with DNS standards and avoids potential issues with domain name resolution. Further updates to these guidelines may be necessary as we develop support for additional domain levels.