Introduction to the principle of DNS

author ： Shi Zhenzhen , CSDN Blog star Top5、Kafka Contributor 、nacos Contributor、 Hua Wei Yun MVP , Tencent cloud TVP, sound of dripping water Kafka technician 、LogiKM PMC( Change of name KnowStream).

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LogiKM( Change of name KnowStream) It is open source by Didi Kafka Operation and maintenance management platform , Students who are interested in participating in the development , But students who are afraid of their own lack of ability , You can contact me , When your mentor takes you to open source ！.

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One 、 Ubiquitous threats

1. Preface

Relevant codes as the core assets of the company 、 Documents exist in our office environment , Many companies have written regulations that these core assets cannot be spread , But many times our computers have many threats , For example, phishing websites , Hacking Trojan horse and so on .
Some time ago, it was reported that NVIDIA's core code was under threat , Some core secrets of Intel have also been leaked , These shocking cases always remind us that we need to pay attention to the security of the office network .

2. Protection ideas

Many times, the reason why we get caught is that we visit websites that we shouldn't visit or open software that we shouldn't open , In essence, we exchange information with unknown websites , So if we maintain a list of dangerous websites , Just don't visit ？ And now many websites have cdn Speed up our access , If we can access different acceleration nodes according to our location, we can even optimize the quality of our network , All the ideas are related to one called DNS It's all about .

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Two 、DNS What is it?

1. Principle introduction

DNS： The domain name system (DomainNameSystem)
A core service of the Internet , Equivalent to the Internet GPS, It can be seen as a huge address book , When the host accesses the domain name , hold The URL is parsed into the corresponding IP Address .

Generally speaking , We will have a local cache DNS, If the local cache DNS
When there is no time, you will access the specified DNS The server goes to find the target address . Like the picture above ,DNS The server will find its own address book and return it to the terminal .

2. Tradition DNS The problem of

From the principle, we know that our network access mainly depends on DNS The server , however DNS Where does the address book in the server come from ？ This is DNS The root domain name server in the infrastructure of .
For example, we visit baidu.com, But our DNS When there is no corresponding address in the server, it is the process in the following figure ：
So our access speed will depend on DNS Does the server have this cache , If not, recursive access will take too long .
In addition, the final address we access depends on the records in a domain name server , quite a lot cdn The implementation of is to visit different top-level domain name servers and resolve to different locations to achieve acceleration , It's not particularly accurate .
And if we are in some bad online environment ( Internet cafes in childhood ) You can see many advertising pages on any page , One reason is DNS hijacked , In fact, no matter you go to any website, you will find a specific ip, Then it will add many small advertisements to the website you visit and return them to you .
Last , Remember that Russia was sanctioned , The way to erase Russia from the Internet is actually as long as the top-level domain name service and sub domain name servers restrict Russia ip Address access can be done , It's also a project that gets stuck .

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3、 ... and 、 How to optimize

1. Solutions

With the above knowledge , We can have some optimization ideas .
We set up a local DNS The server , Record all analytic contacts , Then put all the dangerous ip Screen out , Then according to different visits ip To resolve to different cdn Accelerating the server can achieve our goal of optimization and security ？
But it seems a little too troublesome , Is there any ready-made solution ？

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2. Out of the box way

The way mentioned above is actually OneDNS The core operation mode of , And because it is finished software , The information collected will be more comprehensive than ours , Improve more security . And the public service version of the software recently announced that it will be permanently free .
From the above DNS Knowledge points we find that it will have many advantages ：

• light ： Light access , Light operation and maintenance .10 Minutes to deploy , Detection upon access / Intercept , Visual management of multi branch workplace with a single console ;
• steady ：9 Annual stability 100% Non disruptive operation , Automatic load balancing 、 Automatic failover , National Intelligence acceleration ;
• accurate ：99% Accuracy of threat detection , The cloud Threat Intelligence base is updated in real time ;
• whole ： Common office scenarios in enterprises are fully supported , Office terminal types are fully covered .

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3.OneDNS The future of

OneDns In addition to the official announcement, the public service edition is permanently free , There are also major updates , such as ：

• On a national scale OneDns Node expansion , Provide better parsing services with higher performance , In particular, the number of service nodes in Beijing, Shanghai and Guangzhou has more than doubled ;
• Full support IPv6, And support dynamic lines DDNS distinguish , Give Way OneDNS The public service version has a more comprehensive network access capability , Serve a broader group of enterprise users ;
• Lighter and quieter Agent.OneDNS To optimize the Agent, Support silent installation 、 Silent operation , Make it easier for enterprises to manage remote office terminals , At the same time, it does not compete for terminal resources , Does not affect the end user experience ;
• Make the switch between public service version and enterprise version more smooth , Provide more flexible choices for enterprise office network security .

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5、 ... and 、 summary

OneDns utilize DNS Optimize our network quality and improve security , It provides us with out of the box DNS Server Solutions

And it's free forever , It is strongly recommended that you try it yourself , As long as you register, you can try it for free. Move your little finger to apply .

Of course, if you are right DNS Domain name resolution catch up with interest or have any questions , Can contact me to communicate , We study together, make progress and become stronger .

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