Why Change DNS Server Settings in Mac OS?Įvery Internet service provider manages their own DNS servers. DNS is basically a directory containing IP addresses of all the websites present on the Internet. When you type in the domain name in your mac browser and press enter, the computer will contact a DNS server to find the IP address associated with the domain name.
CAN YOU USE MULTIPLE DNS SERVERS MAC HOW TO
Learn how to find IP address of a website server How DNS works? It masks the IP addresses and gives them a domain name so that you can remember it easily. Similarly, for the Mac to load a website, you need type in the website IP address into a web browser.īut the problem is that IP addresses are quite difficult to remember.
If someone has to find your house, then that person requires your address. Let us understand with the help of an example. What is DNS?Įvery website on the Internet is connected to an IP address. In this article, all your queries regarding how to change DNS mac will be answered. Hence, it becomes crucial for every Mac user to know how to change DNS server settings. But if the DNS servers of your Mac are not functioning properly, then the websites may slowly or not load at all. Many people are not aware of this fact and completely ignore Mac DNS server settings. I wasn't able to find any reference on this but IIRC from the very back of my head, Apple once mentioned on a WWDC that they are now more aggressive at DNS querying and may even try to contact multiple DNS servers at once with the fastest one winning in some cases but I might be wrong on this (maybe this was iOS only or so).Mac uses Domain Name System (DNS) to access websites on its browser. This cnet article explained how this can be disabled but I'm not sure this is still possible in current systems. Every time that happens, the secondary server becomes the primary one, see this older knowlebase article. If it constantly falls back to the secondary one, it may consider the primary one to be too slow. In your case, though, I'm afraid something is wrong with your primary server as by default, macOS will only use the primary one. Some will just alternate between them as a poor man's load balancing. Some may also prefer the primary one but do some kind of load balancing and switch to the secondary one if more than a certain amount of queries are currently pending on the primary one. Some may also query both at once, make the faster one win and then keep using that one for a while (until they start another race to see if it is still the faster one). Some systems may send a request to the primary one but if no reply comes back within a few seconds, they don't resend to it but first try the secondary one (then they resend to the primary one and so on). As both DNS servers are supposed to deliver the same result for the same domain (if not, your setup is actually flawed as the secondary should be a 1-to-1 replacement for the primary one), it shouldn't matter which one is being used.
This means it can take up to an entire minute and above to resolve a DNS name if the first DNS server dies.Īs that seems unacceptable, different operating system developed different strategies to handle this in a better way. As an UDP packet may as well get lost and the round-trip time (RTT) is unknown, it will have to resend the request a couple of times, every time waiting for several seconds, before it finally gets to the conclusion that this server is dead. So if a DNS server is offline, the system won't notice that other by not receiving a reply from it. The problem here is that DNS uses UDP and UDP is connectionless. Answering that a name is unknown is a reply. Doesn't reply means "no reply at all", it will not ask the secondary when the primary one said that a name is unknown. it is offline, unreachable, restarting, etc.), the system can fall back to a secondary one, so it won't be unable to resolve DNS names during that time. The general idea of a secondary DNS server was that in case the primary DNS server doesn't reply (e.g.