Introduction to DNS Server Deployment Guide

One of the most important components of any current TCP/IP network is the DNS server. A number of things a DNS server can accomplish, such as parsing an Internet URL into an IP address, resolving the host name on the local network, and providing the infrastructure on which the Windows Active Directory depends. Therefore, deploying a DNS server is not a very simple matter.

To help some novice friends better understand the DNS server, this article discusses some of the experience and common sense of deploying DNS servers, describes the roles that DNS servers can perform, and where the DNS servers should be deployed on the network, and, for your network, How many DNS servers should be deployed is the best choice.

How many DNS servers do you need?

In general, for some large networks, it is not the best way to rely on only one DNS server to meet the needs of name resolution. So how many DNS servers will be able to meet your needs? There may be a lot of factors involved, so let's start with the capabilities of the DNS server.

Instant your DNS server is a medium-configured server, and it can handle name resolution requests that are also amazing. For example, it was previously seen in an old Microsoft article that Windows Server 2003, installed on a Pentium III 700MHz computer as a dedicated DNS server, can handle more than 10,000 name resolutions per second. If Microsoft's data is correct, you can estimate the number of DNS servers you need based on the number of names resolved in your network.

Unless you work in a large company, and when you see this number, you may think your DNS server will never reach this load, then is it enough to deploy a DNS server?

There are many reasons to say that deploying a single DNS server is a bad idea. I will introduce these different reasons in the article. One of the most convincing reasons is the problem of fault tolerance. If you have only one DNS server in your network, and once the DNS server is out of the question, your network will stop functioning properly. Therefore, for fault-tolerant purposes, you will need to deploy at least two DNS servers.

DNS server role

Fault tolerance is just one of the different reasons you need to deploy multiple DNS servers; A DNS server can accomplish several different tasks. Companies typically decide whether to deploy multiple DNS servers based on the roles that these DNS servers perform. Or, in terms of performance, a DNS server can be perfect for multiple roles at the same time, but from a security standpoint, having a DNS server do a lot of other things at the same time is obviously not a good idea, especially if the DNS server is exposed to external, more insecure. Even without security concerns, having a DNS server do two things can obviously affect the performance of this server.

In the following sections, I will describe the different roles that a DNS server can play and the impact on DNS of these roles.