Domain Name Servers Explained and How to Change Yours
Every time you type a web address into your browser, a quiet conversation happens between your device and a global directory. That directory is the domain name system, and the servers that answer those conversations are called domain name servers. They translate the friendly names we remember, like the names of Australian banks, news outlets, or small businesses in Brisbane and Adelaide, into the numeric addresses that computers use to find each other.
Most people never think about these lookups until something feels slow, blocked, or unreliable. Switching the servers your device or router uses is one of the few network tweaks that takes minutes, costs nothing, and can produce visible improvements. The following walkthrough covers what a domain name server is, why Australians often change them, and the practical steps for doing it on the equipment people actually use at home and in small offices across the country.
What a Domain Name Server Actually Does
A domain name server, often shortened to DNS server, is a specialized computer that answers questions of the form "what is the IP address for this domain name". Think of it as a phone book that turns names into numbers. When you type a site address into Chrome, Safari, Edge, or Firefox, your operating system first checks a local cache, then sends the question to a recursive resolver provided by your internet service provider or a third party you have configured.
If that resolver does not know the answer, it asks a root server, then a top-level domain server (such as the one responsible for .com, .org, or .au), and finally the authoritative server for the specific domain. Each step is fast, but the round trips add up. The whole exchange typically takes tens of milliseconds on a healthy Australian NBN connection, although congested international paths can stretch it further.
A small point worth knowing is that Australian country-code domains, ending in .au, are administered by auDA, the .au Domain Administration. Authoritative answers for those names therefore live on servers operated by accredited registrars, which means local lookups for Australian sites can sometimes resolve faster than people expect, especially when the resolver is also located in Australia.
How a DNS Query Travels Across the Internet
Picture a Sydney-based reader who wants to load a Melbourne news site on a Telstra NBN line. The browser sends a UDP packet, usually to port 53, asking the configured resolver for the IP address. That first hop is the only one the user controls directly. The resolver then performs the recursive work described above, possibly using anycast addresses that route the request to a data centre in Sydney, Melbourne, or somewhere overseas.
Responses include a time-to-live value that tells other resolvers how long to cache the answer. This is why a site that recently moved servers can appear "broken" for some users long after the change has technically gone through. Clearing the local DNS cache on the device, or waiting for the TTL to expire, is usually enough to recover.
Modern DNS also supports encrypted variants known as DNS over HTTPS (DoH) and DNS over TLS (DoT). These wrap the lookup in encryption so that intermediaries on the network cannot easily see which names you are resolving. Australia's Telecommunications (Interception and Access) Act 1978 and the related assistance obligations mean some local providers retain metadata about lookups for lawful purposes, which is one reason privacy-conscious users in Perth and elsewhere look beyond their default resolver.
Why Australians Switch Their DNS Settings
There are four common motives, and they often overlap. The first is performance. Default resolvers from major ISPs such as Telstra, Optus, and TPG are usually reliable, but during evening peak hours they can become congested, slowing the first byte of every page load. A third-party resolver with Australian points of presence can sometimes shave noticeable milliseconds off this delay.
The second motive is censorship circumvention and content access. Some networks block adult content at the resolver level, either because of family filters requested by the account holder or because the network operator has applied a default filter, as is sometimes the case on public Wi-Fi in libraries, cafes, and hotels across Adelaide, Brisbane, and smaller regional centres. Switching to an unfiltered resolver is one way to bypass these blocks, although it does not override application-level restrictions.
The third motive is reliability during outages. When an ISP's resolver goes down, every site that is not already cached becomes unreachable, even though the underlying internet connection is fine. A backup resolver configured on the device or router keeps things working in that window. The fourth is privacy and security, especially the desire to use encrypted lookups and to avoid resolvers that log queries for advertising or analytics purposes.
Popular Public DNS Services Compared
| Provider | Primary Address | Secondary Address | Notable Features | Australian Presence |
|---|---|---|---|---|
| Cloudflare | 1.1.1.1 | 1.0.0.1 | Free, no logging of querying IP, supports DoH and DoT | Yes, nodes in Sydney and Melbourne |
| Google Public DNS | 8.8.8.8 | 8.8.4.4 | Long-established, broad reach, DoH and DoT support | Yes, nodes in Sydney |
| Quad9 | 9.9.9.9 | 149.112.112.112 | Blocks lookups for known malicious domains | Limited Australian footprint |
| OpenDNS (Cisco) | 208.67.222.222 | 208.67.220.220 | Optional content filtering, paid tiers available | Limited Australian footprint |
| AdGuard DNS | 94.140.14.14 | 94.140.15.15 | Built-in ad and tracker blocking, family mode | Yes, with anycast nodes in Oceania |
Each of these resolvers can be configured at the operating system level, the router level, or both. Configuring at the router level applies the change to every device on the home network in one go, which is convenient but means guests also use your chosen resolver. Configuring at the device level is more selective but requires repeating the change on each phone, laptop, or smart TV.
Changing DNS on Windows, macOS, Routers, and Phones
On Windows 10 or 11, open Settings, then Network and Internet, then either Wi-Fi or Ethernet depending on how the machine connects. Choose the active connection, select IP assignment, and switch from automatic to manual. Turn on IPv4, then enter the preferred and alternate DNS addresses from the comparison table above. The settings take effect immediately, although a quick browser restart helps confirm the change.
On macOS, open System Settings, choose Network, select the active interface, click Details, then DNS. Use the small plus button to add each new resolver address, and drag them above any existing entries. Apple has supported encrypted DNS in macOS since Big Sur, so DoH and DoT hostnames can also be entered here rather than raw IP addresses if preferred.
Most consumer routers sold through JB Hi-Fi, Harvey Norman, or directly from NBN providers expose DNS settings under a section labelled Internet, WAN, or DHCP. The exact location varies by brand, but the principle is the same: replace the ISP-supplied resolvers with the public addresses of choice. Because this change affects every device that connects through DHCP, including smart TVs, game consoles, and IoT gadgets, it is often the most efficient option for a household.
On iPhone and iPad, open Settings, tap Wi-Fi, select the active network, choose Configure DNS, switch to Manual, and add the chosen addresses. A similar flow exists on Android under Network and Internet, then Private DNS, where a hostname can be entered to enable encrypted resolution without touching individual IP entries. For Australians travelling or living in regional areas with satellite or fixed-wireless NBN services, switching resolvers can be especially valuable because the long path to overseas servers benefits most from a resolver that caches aggressively and is geographically close.
Troubleshooting DNS Problems After Switching
If a site stops loading after a DNS change, the first step is to confirm that the new resolver is actually reachable. A quick command-prompt ping to the chosen IP address, or a traceroute, shows whether packets are leaving the network at all. If they are not, the firewall on the router may be blocking outbound port 53 to anything other than the ISP's resolver, which is a known issue on some older ISP-supplied modems.
A second common problem is leftover cache. Windows keeps a DNS resolver cache, macOS uses a similar local store, and browsers maintain their own internal cache. Running ipconfig /flushdns on Windows or sudo dscacheutil -flushcache on macOS clears the operating system cache and forces a fresh lookup. Closing and reopening the browser clears its own store on top of that.
For deeper investigation, tools such as nslookup and dig let you query a specific resolver directly and see exactly what answer comes back. Combined with a leak test, these utilities cover almost every diagnostic question a non-specialist is likely to have. Readers who want a more detailed primer on caching, TTL behaviour, and resolver selection can review DNS fundamentals before making a final choice.
A third issue is split-horizon DNS, where a workplace or ISP returns a different IP address for certain names than the public internet does. Switching to a public resolver on a corporate laptop can break access to internal company tools, which is why many people configure DNS on a per-network basis rather than globally. The same caution applies to users of Australian banking apps that occasionally perform security checks against the local network.
Common things to check when a change seems to have failed:
- Confirm the new resolver answers by running nslookup against one of its addresses directly.
- Flush the local cache with the appropriate command for your operating system.
- Disable IPv6 temporarily if your network has misconfigured IPv6 resolvers still taking precedence.
- Try a secondary resolver address, since the primary might be unreachable from your location.
- Reboot the router, especially if the change was made through its administrative interface.
- Revert to the original settings if the issue persists, then troubleshoot from a known-good baseline.
Practical Habits Before You Commit
A few small routines make the whole process smoother and easier to reverse if something goes wrong.
- Photograph or screenshot the existing DNS settings before changing them so you can restore them in seconds.
- Write down the chosen primary and secondary addresses in a note-taking app, or keep a printed copy near the router.
- Configure two resolvers rather than one, so a single outage on the primary does not break lookups entirely.
- Test the change on a single device before applying it at the router level, so any unexpected behaviour is easy to isolate.
- Re-test after major router firmware updates, since some updates silently reset DNS settings back to the ISP default.
- Remember that DNS changes do not always apply to existing browser tabs, so reload or restart the browser to confirm.
Once the change has settled in for a few days, most people find the experience quietly faster, occasionally more private, and very rarely something they need to think about again. The infrastructure doing the work is decades old, surprisingly simple in concept, and yet it is touched by every single thing we do online, from checking the Sydney weather before the commute to streaming cricket on a Friday night.
Pick a resolver from the comparison table, apply it on a single device, and run a quick leak test to confirm the change is live. If the result looks right, extend the same configuration to your router so every connected device benefits from the new path. Many Australians find that switching to a resolver with local nodes makes their usual sites noticeably snappier, and the small effort required pays off for as long as they stay with that provider.