Router DNS vs. Windows DNS

Participant · 10 Oct 2015 at 18:40

Hi all

If my router's DNS is set to 8.8.8.4 / 8.8.4.4 (i.e. Google) and my Windows PC is set to 'obtain automatically', what DNS address will actually be used?

What about if my PC is set to use, say, Virgin's DNS servers?

Thanks.

Danny091 · 10 Oct 2015 at 18:42

Generally your PC will set your routers IP for DNS lookup and then your router will forward it to the ones you have set it too. (Defaulting to virgin's) if you didnt change it.

www.dnsleaktest.com if you want to see what DNS your pc is using.

bremen1874 · 10 Oct 2015 at 18:45

Your router's DHCP server will set the PC's DNS to whatever the router is set to.

If you set them manually on the PC it'll use what you've set.

IPCONFIG will show you what it's set to.

bledd · 10 Oct 2015 at 19:55

You want your PC to use the router's DNS, otherwise it won't be able to see any other local machines.

If your router is set to use 8.8.8.8, then it will look up DNS through that and sent it to your PC.

Ie, if your router IP is 192.168.1.1, that's what your gateway and DNS should be set as on your PC.

bremen1874 · 10 Oct 2015 at 20:08

There are other ways for Workgroup PCs to resolve network names. If you're running a domain then you need DNS, but that isn't the usual home setup.

Or I could be wrong...

Sparx · 10 Oct 2015 at 20:52

Curious on this topic too, I've always wondered whether it was best to set DNS via the router's WAN or DHCP server? I've been told DHCP as it uses less CPU cycles on the router...

bremen1874 · 10 Oct 2015 at 21:08

How would you set DNS via WLAN? That makes no sense to me at all.

Danny091 · 10 Oct 2015 at 21:14

bremen1874 said:
How would you set DNS via WLAN? That makes no sense to me at all.

He means set the dns manually as part of the WAN connection (dont auto connect to ISP's use my own) This way the computers ext just use the router to forward DNS requests to google or open dns or whatever

or set the DHCP server to send the actual ip's of the dns servers to the computers so that it bypasses asking the router.

Way 1) you get to use whatever dns you want however devices just use the router as the DNS and the router forwards it

2) the actual devices have the IP of the dns servers bypassing the router.

ipconfig
192.168.0.1 for option 1 the router forwards it to 8.8.8.8
8.8.8.8 for option 2

Steveocee · 10 Oct 2015 at 21:24

I don't understand the obsession with Google DNS, your ISPs DNS should be the shortest hop and be reliable.

I set my machines to use my local DNS and that draws from my ISP first followed by Google then open DNS

Participant · 10 Oct 2015 at 21:48

Cheers guys, lots of useful info. That link confirms I'm using Google dns.

I wouldn't call it an obsession, I'm just experimenting as Google.co.uk takes far longer than it should to load for some reason, so I wanted to try Google DNS to rule out that being the issue.

No change, so I guess it's a software problem (only noticed it since upgrading from Windows 7 to Windows 10.

Sparx · 10 Oct 2015 at 22:51

Danny091 said:
He means set the dns manually as part of the WAN connection (dont auto connect to ISP's use my own) This way the computers ext just use the router to forward DNS requests to google or open dns or whatever

or set the DHCP server to send the actual ip's of the dns servers to the computers so that it bypasses asking the router.

Way 1) you get to use whatever dns you want however devices just use the router as the DNS and the router forwards it

2) the actual devices have the IP of the dns servers bypassing the router.

ipconfig
192.168.0.1 for option 1 the router forwards it to 8.8.8.8
8.8.8.8 for option 2

Yes mate, typo I've corrected my post to WAN.

Does anyone know if there is any benefit whether the DNS is set in the WAN, DHCP or both? :confused:

DIABLO · 11 Oct 2015 at 17:06

If ony of you guys run a home server it can be good to set that up as a DNS server.

KIA · 11 Oct 2015 at 18:44

bremen1874 said:
There are other ways for Workgroup PCs to resolve network names. If you're running a domain then you need DNS, but that isn't the usual home setup.

Or I could be wrong...

You're right.

Steveocee said:
I don't understand the obsession with Google DNS, your ISPs DNS should be the shortest hop and be reliable.

Lowest latency? Probably.
Most reliable? Not always.

Steveocee · 11 Oct 2015 at 18:55

KIA said:
Lowest latency? Probably.
Most reliable? Not always.

I should have worded that better, "decent ISP's DNS"

On Holiday · 11 Oct 2015 at 18:55

I use Google/other DNS than my ISP as I prefer not having to wait so long for DNS propagation nor do I want to edit hostfiles.

Liquidfox · 11 Oct 2015 at 22:47

As a business we always use the ISP DNS as the first two and then Google as the third. Latency is key for business users, if it takes any longer than 2-3 seconds they're on the phone complaining their entire PC is slow because they can't get on Facebook quick enough...

Steveocee · 12 Oct 2015 at 08:39

Liquidfox said:
As a business we always use the ISP DNS as the first two and then Google as the third. Latency is key for business users, if it takes any longer than 2-3 seconds they're on the phone complaining their entire PC is slow because they can't get on Facebook quick enough...

Router with DNS caching is brilliant for this.