My N00b question regarding setting up alternate DNS

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Easto
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My N00b question regarding setting up alternate DNS

Post by Easto »

I'm a little confused regarding the settings used in order to bypass my ISPs DNS server and use an alternate DNS server. I started to think I may have this wrong when I decided to run a few Tracerts. And, it could be that either I don't understand or I do in fact have something setup incorrectly.


My ASUS RT-AC3200 router
DNS Server 8.8.8.8
Wins Server 8.8.4.4


I have also noticed that in my Chrome browser settings under privacy and security there is a setting "Use secure DNS" and this allows me to set it to the Google DNS if I like. I guess I'm wondering if one of these settings may be negating the other? It may also be that I don't understand the Tracert process and what I'm getting as results. Do I have this right or am I missing something?


Example:


Tracing route to speedguide.net [68.67.73.20]
over a maximum of 30 hops:


1 <1 ms <1 ms <1 ms RT-AC3200-A8B0 [192.168.1.1]
2 * * * Request timed out.
3 9 ms 10 ms 7 ms lag-60.dtr02lnbhca.netops.charter.com [96.34.63.98]
4 11 ms 15 ms 10 ms lag-25.crr03rvsdca.netops.charter.com [96.34.96.28]
5 11 ms 11 ms 10 ms lag-811.bbr01rvsdca.netops.charter.com [96.34.3.18]
6 12 ms 16 ms 11 ms lag-801.prr01lsanca.netops.charter.com [96.34.3.129]
7 * 13 ms 12 ms lag-22.ear4.LosAngeles1.Level3.net [4.68.37.153]
8 80 ms 78 ms 78 ms ae1.3510.ear1.Jacksonville5.level3.net [4.69.132.70]
9 79 ms 84 ms 79 ms SBA-EDGE-LL.ear1.Jacksonville5.Level3.net [65.57.158.82]
10 92 ms 91 ms 97 ms te-4-1-1131-40g-east.core-a.jcvnflcq.jax.as19844.net [216.238.150.207]
11 80 ms 79 ms 79 ms xe-0-1-2-1131.scolo-c10.jcvlfljb.jax.as19844.net [216.238.150.131]
12 78 ms 76 ms 77 ms speedguide.net [68.67.73.20]


Trace complete.
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Philip
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Location: Jacksonville, Florida

Post by Philip »

It is actually an excellent question :)

Basically, the DNS settings in your router are the default, as long as your clients/PCs are set to obtain IPs automatically (via DHCP). If you set DNS manually in the PC's network adapter settings, or in the web browser, you are overriding the default DNS from the router to the one you set in your browser or network adapter.

Once a name is resolved, it is remembered in local cache for a couple of hours, so that new DNS lookups are not necessary.
This also goes for Google's, or your ISP's DNS servers, they have their own cache, so that once they resolve a host from the "authoritative" server, they cache it for a while to reduce load/latency of resolving it again.

The "secure DNS" option usually is intended to bypass your ISP, and any malicious third party in the middle of your connection to a server that may attempt to log/track/hijack DNS responses.

I hope this makes sense.
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