how does DNS work with VPN

[jeyf]

reference:
macOSX = Catalina 10.15.7
early 2016 iMac and 2017 MBP
Brave broser with cookies & scripting = ON
the VPN application is initilized at power up
FIOS all in one box = Zyxel c2100z

with my private VPN running:
Sometimes i am having issues with a web sites resolving, the Brave borwser indicator is spinning counter clockwise. Slow performance but eventually it resolves in a few minuites..

i initially setup both the iMac & MBP as:
SystemPreferences -> Network -> Advanced -> DNS = 192.168.200.1 / "house1"

i notice:
-when running the vpn applicaiton it connecting to US or Asian based destinatuions, the Sys Pref DNS domain = "openVPN" but the ip address can varry. Intermittant performance but most of the time it work and the DNS resolves in a second or two. Even when the Sys Pref DNS changes to "openVPN" this is no guarantee the DNS will resolve as expected.
-sometimes the vpn application dosnt modify the Sys Pref DNS settings and it stays 192.168.200.1 / house1. This always leads to the above slow performance


i hae an iPhone7 with 14.3 and installed the free ios app form openVPN. I obtained openVPN config files form the private VPN web site. Both domestic and international connects work w/o issue.

anything helps here including basic network theory on DNS vs VPN.


a side note is:
-how private is the openVPN's DNS choice?
-is my internet providor altering the DNS selection?

thanks in advance.

 

[MacBH928]

1. Browsing with VPN is slower
2. OpenVPN is secure to usee
3. VPN provider uses their own or other DNS servers, not your ISP, so don't worry
4. Check https://ipleak.net test to see if there is DNS leaking and if your ISP is altering somehow
5. I can't help if you are setting up your private VPN, but this is as secure as browsing without VPN(if not on public Wifi network)

 

[jeyf]

i use openVPN on my iPhone with the same VPN provider. It works w/o issue. Maybe uses significant battery. So am reluctant to change my VPN provider unless they can run on my iPhone7.


i have 1Gb fiber and am not able to connect my open soure router directly to the fiber. Unable to negociate my embedded fiber user id and pw on their system. I can put the fiber modem box in pass through mode but it behaves badly. Just thinking about a rumor i read that some fiber providors are over writing the customer's DNS with their own.

 

[MacBH928]

Some devices do force using their own DNS, YES, but if you enable a VPN on your device like macbook or iphone it will be ignore. I am not sure what happens if you enable the VPN on the router itself.

I am not sure I understand your setup but if you don't find the help you need here I encourage you to join reddit and ask in this community : https://www.reddit.com/r/HomeNetworking/

 

[jeyf]

I am hoping this statement points the iMac to the PFSense box for all its non VPN DNS needs.
implementing it on a iMac by defining Catalina 10.15.7 SystemPreferences -> Network -> Advanced -> DNS
Search Domains = MYhouse
DNS Servers = 192.168.1.1 //the address of the pfSense box

sometimes with the VPN operatonal for domestic servers the settings are changed as SystemPreferences -> Network -> Advanced -> DNS screen changes like
Search Domains = openvpn
DNS Servers = 103.86.96.100 & 103.86.99.100

sometimes with the VPN operatonal for asian servers the settings are changed as SystemPreferences -> Network -> Advanced -> DNS screen changes like
Search Domains = openvpn
DNS Servers = 1.1.1.1

-i dont fully understand the Searh Domains setting
-i grabbed another mac computer this morning. A MBP we use in the house and it reliably operated the VPN; resolveed names into ip addresses with out delays. Comparing this computer to the iMac i oculd not really see any differnces that would matter. I manually moved the iMac lan ip address from 192.168.1.49 to 192.168.1.22 and reset the router. the iMac, the VPN for a asian server, started working but the SystemPreferences -> Network -> Advanced -> DNS settings were = MYhouse / 192.168.1.1 so go figure??

1Gb fiber -> fiber modem -> pfSense firewall -> router
the router has hard wire ethernet for:
airpport extreem wifi (MBP & other wifi devices)
the iMac & other ethernet cabled devices)

FYI; i was using the ios network tool from Fling

anyways an interesting problem. It seems to be working now but...