[Hongke technology sharing] how to test DNS server: DNS performance and response time test

What is domain name resolution  

In-depth study on how to test DNS Before server , Let's talk about DNS What it is and how it works .DNS Indicates the domain name system . It is used to transform domain names from human readable forms （ for example google.com） The conversion is called IP Machine readable value of the address （ for example 142.250.217.78）. Every website and device on the Internet needs a unique IP Address is the only way to communicate , therefore DNS Servers play an important role in Internet functions . however ,DNS Just a group called DDI A component of Web Services , These services are supported by IP To communicate over the Internet .

DDI yes DNS（ Domain name service ）、DHCP（ Dynamic Host Configuration Protocol ） and IPAM（IP Address management ） General term of integration .

DHCP It is dynamically distributed in the network IP Address system ,IPAM It is a kind of tracking and management on the network IP Address space method ,DNS Essentially, it acts as a phone book , Used to record all existing IP Address and manage the mapping between domain names and numbers .

DNS How to work

When you are in Web Type the domain name or URL when ,DNS The server will convert the request to IP Address . This request is called a query . It enables the machine to connect you to the correct remote host and provide the corresponding web pages .

1. The user types Web domain name .

2. The browser will DNS Queries are sent to their local DNS The server , Also known as recursion DNS Server or DNS Parser .

3. If recursion DNS The server has responded to the domain request stored in its cache , It will return IP Address , also Web The browser will display this page .

4. If recursion DNS The server does not cache the query response , It will pass Authority DNS The hierarchy of the server forwards requests , In order to find the corresponding IP Address - It still takes only a fraction of a second .

The recursive server uses each domain name IP Address cache a record , So that you can respond directly next time , Without contacting other servers . recursive DNS Servers are used locally to reduce Authority DNS Server load , Because otherwise, a large number of requests cannot be processed . Consider how many people are using the Internet at any given time .

This is why large-scale testing DNS The reason why servers are critical to avoiding performance bottlenecks or crashes . Please read on , Learn about DNS More information about testing .

DNS test ： How to test DNS Server performance  

DNS The server is hit by thousands or even millions of queries per second , And you need to send a response as quickly . In order to DNS Servers perform performance tests and ensure that they can handle a large amount of load , Organizations should use large-scale DNS The test device generates millions of unique queries per second , And verify whether the server responds appropriately in time . If you are right about DNS There are any questions about the response time test or other products we provide , Please feel free to contact us .

 

There are many different types of DNS Inquire about , The most common ones are listed below ： 

Domain name resolution request type

• A （IPv4）

• AAAA （IPv6）

• PTR（ Domain name pointer ）

• NS（ Authoritative name server ）

• MX（ E-mail exchange ）

• TXT（ Text string ）

• SRV（ Service record ）

• NAPTR（ Naming authority pointer ）

• CNAME（ Domain name alias ）

The server can also return various DNS Response code , Some of these codes are listed below ：

DNS Response code

• No mistake

• Format error

• Server failure

• A nonexistent domain

• Unrealized

• Query rejected

Thoroughly test DNS Server performance and capacity , Valid and invalid requests need to be sent . Invalid queries can cause cache misses , And further DNS The server performs a stress test .

By creating and maintaining global URL Main list of ,DNS The test tool can measure the actual response of the server to valid and invalid queries . A good DNS The test equipment will be able to evaluate the transmission , Completed and missing queries , Trace response code , And measure the delay of query response time . These indicators will provide DNS Clear indication of server performance , And provide optimization for engineers DNS Servers or deploy more if necessary DNS Information required by the server .