Managing a domain involves more than just registering and owning it; it also requires proper configuration of name servers (NS – nameservers). In the Czech domain space (.CZ), a specific system called NSSET is used for this configuration, managed by CZ.NIC. This article explains what NSSET is, how to create and manage it, and its benefits.

What is NSSET for .CZ Domains?

NSSET stands for Name Server Set, a predefined group of name servers that allows multiple domains to share the same configuration. Instead of manually entering individual name servers for each domain, you can simply assign an existing NSSET, streamlining domain management.

Why Use NSSET?

NSSET offers several advantages for domain management:

• Simplified management of multiple domains – instead of setting up servers individually, you can apply one set to multiple domains.
• Faster updates – when modifying name servers for domains using the same NSSET, you only need to update the settings once.
• Security and standardization – managing DNS through predefined sets reduces errors and improves oversight of domain configurations.

How to Check the NSSET Assigned to a Domain?

Each .CZ domain has an assigned NSSET, which can be checked via a WHOIS query on the CZ.NIC website or through the registrar's interface.

To check NSSET using the WHOIS command in a terminal: whois example.cz

The response will include the NSSET record, indicating which name servers are assigned to the domain.

How to Create a New NSSET?

Creating an NSSET is done through the domain registrar or directly via the CZ.NIC system. The process includes:

1. Logging into the registrar’s control panel – most registrars provide an interface for creating NSSETs.
2. Defining name servers – at least two name servers must be specified (e.g., ns1.example.com, ns2.example.com).
3. Verifying name server validity – some registrars require validation before assigning name servers.
4. Receiving the NSSET identifier – once created, the NSSET is assigned a unique identifier (e.g., NSSET123456).

How to Assign NSSET to a Domain?

Once an NSSET is created, it can be assigned to a specific domain using the following steps:

1. Log into the domain registrar’s control panel.
2. Find the domain to which you want to assign the NSSET.
3. Select an existing NSSET or enter its identifier.
4. Save changes and wait for DNS propagation (which may take a few minutes to several hours, depending on TTL settings).

How to Change the NSSET of a Domain?

If you need to update the name servers for a domain, you can either:

• Modify the NSSET itself – if multiple domains use the same NSSET, updating it will automatically apply the changes to all associated domains.
• Assign a different NSSET to the domain – if you want to use a different set of name servers, simply enter the new NSSET identifier.

How Long Does It Take for NSSET Changes to Take Effect?

Once an NSSET is modified or assigned to a domain, changes must propagate across the DNS system. This process, known as DNS propagation, typically takes a few minutes to 48 hours, depending on the TTL (Time-To-Live) settings of previous DNS records.

Common Errors and How to Avoid Them

• Invalid or inactive name servers – ensure all servers are properly configured before assigning an NSSET.
• Incorrect NSSET assignment – double-check that the NSSET contains the correct DNS records before applying it.
• Changes not appearing immediately – if DNS updates do not reflect instantly, wait for full propagation.

NSSET is an efficient tool for managing name servers for .CZ domains. It simplifies domain management, speeds up DNS changes, and minimizes the risk of configuration errors. If you manage multiple domains with similar DNS settings, using NSSET for centralized management is highly recommended.