Concepts

This product is in the BETA phase.

Most functions are available, but the full scope of functionality may not yet be implemented. Testing of the product is not finished. Handling may still be inconvenient in places and may not yet fully meet our standards. In the course of development, there may still be changes to operating procedures and processes.

Thank you for your understanding.

A DNS Resolver is a fundamental component in the DNS (Domain Name System) that acts as an intermediary for your computer. Its primary job is to translate human-friendly domain names (like example.com) into the numerical IP addresses (like 192.0.2.1) that network devices use to locate each other. Think of it as a directory assistance operator for the internet.

Recursive Query Handling

When your device needs to find an IP address, it sends a simple request to a resolver. The resolver then performs all the necessary steps to find the answer on your behalf in a process called a recursive query. It does the “legwork” by communicating with several levels of DNS servers across the internet until it finds the definitive answer.

The typical steps for a lookup are:

1. User Request Your computer asks the resolver, “What is the IP address for www.example.com?”
2. Cache Check The resolver first checks its local memory (cache) to see if it has recently looked up this same address. If so, it returns the stored answer immediately. 3. Root Server Query If the address isn’t in the cache, the resolver contacts a Root DNS Server. The root server doesn’t know the IP address, but it knows where to find the servers that manage the top-level domain (TLD), in this case, .com. It directs the resolver to the .com TLD servers. 4. TLD Server Query The resolver then asks a .com TLD Server, “What is the IP address for www.example.com?” The TLD server responds with the address of the specific name servers for that domain. 5. Authoritative Name Server Query Finally, the resolver queries the Authoritative Name Server for example.com. This server holds the official records and provides the final answer: the IP address for www.example.com is 192.0.2.1. 6. Response to User The resolver passes this IP address back to your computer. It also stores this result in its cache for a set period, speeding up future requests.

Caching

To ensure speed and efficiency, resolvers cache (temporarily store) the results of recent queries. When another request for the same domain name arrives, the resolver can instantly provide the answer from its cache instead of repeating the entire multi-step lookup process. This not only makes browsing faster but also significantly reduces the traffic load on the global DNS infrastructure. Each cached record has a specific lifetime, called Time to Live (TTL), after which it expires and must be looked up again to ensure the information is fresh.

STACKIT DNS Resolver IPs

The IP addresses of the STACKIT DNS Resolvers are

EU01

• 192.214.161.53
• 213.17.17.17
• 188.34.111.111

EU02

• 45.137.172.101
• 45.137.172.102
• 45.137.172.103

Architectural Considerations

Scope: The resolver is intended exclusively for workloads within the STACKIT Cloud.