I’ve mentioned DNS (Domain Name Services) before (here, here and here), but I have not yet written about what are the best IP addresses for customers to use when configuring a PC or network to access the Internet. There are a few things to consider when setting this up, and while most techs are familiar with the procedure I thought I would share a few tidbits of my knowledge with the rest of you.
This article came about because recently Skyway West added new DNS IP addresses online for our clients. This may have been confusing for some so I decided to write this in the hopes of making things as clear as possible. To begin, the new Skyway IP addresses are:
The old addresses of 220.127.116.11 and 18.104.22.168 are not being replaced — at least not in the foreseeable future — so there are no immediate changes necessary. We will, however, be providing the new IP addresses to customers when required.
First, what does DNS do? The DNS performs the function of turning words that humans are most comfortable with into numbers (like the new Skyway IP addresses above) that computers can handle and back again. All the sites, servers and computers that are on the web are assigned a numerical address. These numbers are quite long. As humans it is easier for us to remember www.this_is_a_web_page_name_I_need_to_remember.com than a long string of numbers. DNS makes it possible for us to use the name instead of the number. So what numerical DNS servers should you use?
The general theory is that DNS servers closer in proximity to your Internet connection are the best to use because they will provide the fastest response to any query you make. This is usually true but there are instances (which I will get into in a moment), where this isn’t a practical option. Realistically, we are talking about differences of milliseconds, so whichever option you decide on your internet access should be fine. With this in mind I would like to go through a few scenarios using different network configurations and what I think the best options are for each scenario. My solutions may not be the only alternative and you may have other ideas. I present these options as, at the very least, starting point for your consideration…
DNS for a single PC, and up to several computers, connected to a Switch or Router:
This is typically the simplest configuration. The Internet Service Provider( ISP)’s DNS is set up on the network router or each PC and each PC uses that DNS to find its way through the Internet. The configuration is the standard configuration you would find in any home or small office. But what kind of DNS configuration would work for a larger office? Would the configuration mentioned above work well there too?
DNS for Offices that have an internal Domain Controller:
The short answer is yes, the configuration above would work for anyone or any company that doesn’t run their own domain controller. A domain controller is a PC that handles DNS for a company within their network. Companies will often use these servers to help their employees find printers and network storage drives internally (these printers and storage drives are also assigned an IP address). There are issues, however, that need to be addressed with domain controllers. These servers are really quite dumb. By default they don’t know when a request should be found inside the network or outside, so they need to be programmed in order that that they can determine how to look up information to get you to where you need to go.
How to configure a domain controller is a bit complex for this post, but the basic rule is that the servers need to be given two sets of IP addresses. One pair of addresses is assigned to the inside of the network and one pair called DNS forwarders, for the outside of the network (i.e., to the internet). A special file is then created called a zone file which is filled with data that gives the internal DNS all the particulars of the names and assigned IP addresses within the internal network. If a user request comes in and is not recognized as anything valid within the internal network the request is sent to the DNS forwarders to query the Internet for the details.
As far as what external DNS you will be using for your DNS forwarders you could still use those provided by your ISP. So is there ever an instance you wouldn’t use the IP addresses provided by your Internet provider?
DNS for Bonded and Failover Services:
ISPs like Skyway West have used some innovative technologies to give high speed Internet options to our clients without them having to resort to higher priced services such as Fiber. One of those technologies is to bond services together – even services from different upstream providers. While the process works well there is an issue that arises when setting up the DNS. As a means of protection and providing the best connection possible, most ISPs limit the usage of their DNS servers to their own customers. If you bring two different connections together from two different providers, whose DNS should you end up using? Since neither will normally allow DNS queries from another connection you really can’t use either. The solution is to use an outside DNS provider that allows you to use their DNS. Google is one such option. Their DNS servers are currently 22.214.171.124 and 126.96.36.199. This would also be the recommended option for Skyway West clients using a Failover solution.
DNS is a helpful tool that makes it possible for us to get from place to place on the Internet. Depending on your needs there is a suitable configuration that will work. Finding the correct solution shouldn’t be too tricky. If you unsure you are invited to contact Skyway West’s Support desk at email@example.com or 604-482-1212 for assistance. We’re always glad to lend a hand.
Got a question or an idea for a topic you would like to see covered in one of my upcoming posts? Write to firstname.lastname@example.org and sound off. I’ll do what I can to address your questions or concerns either personally in a reply email or on the blog. Until next month, take care.