How to change DNS?

How do I delete a DNS I no longer want to use? (Comcast DNS is still there when i edited with the graphical method.) Thanks for the help.

None of this works my router keeps overwriting my edits and changing my dns back to isp defaults and there is not option in my router that lets me change dns am i screwed?

https://wikileaks.org/wiki/Alternative_DNS

Tramposo
A smart person will try to change the dns on the router settings but if the router is locked out on that option, then you have to change on your computer. In the other hand I use OpenNic to search for the closer geographic location https://servers.opennicproject.org/
example: for my world location I will use either Singapore, honk Kong or japan.
I will start pinging the dns from your location to study the latency then I will start using tracer to study how many hops from your computer to the final destination. For example if you ping with a latency of 57ms or 150ms is a very close. but if your latency is lower in 200 ms or higher then you are too far away. I always using opennic servers.

There is Ways to change your dns on your adsl. It works for me.

1- How to configure a PPPoE internet connection on a Debian box

Assuming your computer has a direct connection (with no router between it and the DSL modem), the configuration is pretty straightforward.
Here’s the tutorial for beginners:
Login and elevate your permissions to ‘super user':

su

Make sure the resolvconf package is installed:

apt-get install resolvconf

Create the directory /usr/etc/ppp:

mkdir -p /usr/etc/ppp

Open your favorite editor (I’m using vi/vim here, so some commands are specific to that editor, like ‘vi’ to use the editor and ‘ :wq’ to write and close. Edit; You may find the Nano editor easier to use), create a new file and enter as many OpenNIC nameserver IPs as you like in, your nearest ones are here.

vi /usr/etc/ppp/resolv.conf.opennic

Enter the following: (The IPs shown here are German, you would probably want the nearest servers to you).

nameserver 78.138.97.33
nameserver 178.63.26.172
nameserver 2a00:e10:1000:10:1586:0:33:53
rotate

Write and save the file

:wq

Note: The “rotate” option helps dividing the requests between the nameservers listed.
Create the following little script:

vi /etc/ppp/ip-up.d/zzz_opennic_resolvconf

#!/bin/sh
# some providers insist on the 'usepeerdns' option, hence
# we reinitialize the resolver to opennic servers after
# all is done. this hook script will be run automatically by
# pppd after it successfully established a connection.
set -e
# before we start: if anything went wrong with pppd, the $PPP...
# variables will not exist.
test -n "$PPP_IFACE" || exit 0
# Logging: use /var/log/ppp-ipupdown.log if it exists (then it is open
# for writing, see ../ip-up). Else use syslog:
blather () {
local whereto
if [ -e /var/log/ppp-ipupdown.log ]; then
whereto="echo $0: $@"
else
whereto="logger -i -t $0 $@"
fi
eval $whereto
}
SYSTEM_RCONF="/etc/ppp/resolv.conf"
# the file we just created:
LOCAL_RCONF="/usr/etc/ppp/resolv.conf.opennic"
test -f $SYSTEM_RCONF || { blather "$SYSTEM_RCONF does not exist. Exiting."; exit 0; }
test -f $LOCAL_RCONF || { blather "$LOCAL_RCONF does not exist. Exiting."; exit 0; }
cat $LOCAL_RCONF | /sbin/resolvconf -a $PPP_IFACE
cp $LOCAL_RCONF $SYSTEM_RCONF
blather "Resolver configured for OpenNIC namespace."

Write and save the file

:wq

Make the script executable

chmod 0755 /etc/ppp/ip-up.d/zzz_opennic_resolvconf

Restart your network:

/etc/init.d/networking restart

And that’s it!

Enjoy!