Setup dnsmasq on OS X

dnsmasq OS X.md

Never touch your local /etc/hosts file in OS X again

To setup your computer to work with *.test domains, e.g. project.test, awesome.test and so on, without having to add to your hosts file each time.

Requirements

• Homebrew
• Mountain Lion -> High Sierra

Install

brew install dnsmasq

Setup

Create config directory

mkdir -pv $(brew --prefix)/etc/

Setup *.test

echo 'address=/.test/127.0.0.1' >> $(brew --prefix)/etc/dnsmasq.conf

Change port for High Sierra

echo 'port=53' >> $(brew --prefix)/etc/dnsmasq.conf

Autostart - now and after reboot

sudo brew services start dnsmasq

Add to resolvers

Create resolver directory

sudo mkdir -v /etc/resolver

Add your nameserver to resolvers

sudo bash -c 'echo "nameserver 127.0.0.1" > /etc/resolver/test'

Finished

That's it! You can run scutil --dns to show all of your current resolvers, and you should see that all requests for a domain ending in .test will go to the DNS server at 127.0.0.1

N.B. never use .dev as a TLD for local dev work. .test is fine though.

Whats the significance of the resolver?

Has anyone used dnsmasq to setup a pre-production testing scenario?

For example:

mylivesite.com is on server 1.2.3.4
mylivesite.com is also migrated to a different server with updates on server 2.2.2.2

I can do this in /etc/hosts file easily enough, however I need to make sure subdomains are working, ideally it would be nice to use dnsmasq's wildcard feature that /etc/hosts can't utilize

echo 'address=/.mylivesite.com/2.2.2.2' >> $(brew --prefix)/etc/dnsmasq.conf

Right now, I can't figure out how to do this with dnsmasq, it's routing to the old server (ie 1.2.3.4)

You should not use .dev or .local if you're developing web applications locally. I stumbled across an issue where my Remix SSR Web App was taking 5 seconds or so to make an API request to the API running on my machine.

https://mywebapp.local -> http://myapi.local

The issue was that .local uses mDNS generally which is reserved for multicasting. This was a cause of my long response times. If you're using dnsmasq for local development, please use .lan.

The .test TLD has been officially reserved by the IETF for testing. I don't think this is the case for .lan.

How about .arpa? https://en.wikipedia.org/wiki/.arpa

Thanks, worked great for me!

@imkonsowa are you on sonoma? I followed all the commands and I still don't get .test to resolve to my localhost

@capaj Yes I'm on sonoma, have you configured a webserver to listen and proxy traffic for a .test host?

Setup MacOS Sonoma networking for the .hack TLD. Including this resource I read

1. https://mjpitz.com/blog/2020/10/21/local-ingress-domains-kind/
2. https://allanphilipbarku.medium.com/setup-automatic-local-domains-with-dnsmasq-on-macos-ventura-b4cd460d8cb3

and concluded the setup for k8s kind, but it also worked to a local nginx webserver running on port 8088

setup

brew install kubernetes-cli dnsmasq
# to keep it dry
export LOCAL_CUSTOM_TLD="hack"
# register .hack TLD locally
echo "address=/.${LOCAL_CUSTOM_TLD}/127.0.0.1" >> $(brew --prefix)/etc/dnsmasq.conf
# configure the local resolver
sudo mkdir /etc/resolver/
cat <<EOF | sudo tee /etc/resolver/${LOCAL_CUSTOM_TLD}
nameserver 127.0.0.1
EOF
# restart local dnsmasq service
sudo brew services restart dnsmasq
# restart mDNSResponder
sudo killall -HUP mDNSResponder
# verify the new resolver was picked up
scutil --dns
# ... should show $LOCAL_CUSTOM_TLD
resolver #8
  domain   : hack # <- 
  nameserver[0] : 127.0.0.1
  flags    : Request A records, Request AAAA records
  reach    : 0x00030002 (Reachable,Local Address,Directly Reachable Address)

test it with a subdomain of .hack

ping -c 1 nginx.random.${LOCAL_CUSTOM_TLD}
# ...
PING nginx.random.hack (127.0.0.1): 56 data bytes
64 bytes from 127.0.0.1: icmp_seq=0 ttl=64 time=0.052 ms

--- nginx.random.hack ping statistics ---
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 0.052/0.052/0.052/0.000 ms

run a local docker container on port 8088 to test it

docker run --rm -p8088:80 --name nginx -d nginx
# test it
curl -I nginx.random.hack:8088

HTTP/1.1 200 OK
Server: nginx/1.25.3
Date: Tue, 12 Dec 2023 12:24:58 GMT
Content-Type: text/html
Content-Length: 615
Last-Modified: Tue, 24 Oct 2023 13:46:47 GMT
Connection: keep-alive
ETag: "6537cac7-267"
Accept-Ranges: bytes

# remove it
docker stop nginx

HTH sb 🎉

For my personal project I solved this by making my LAN IP static in DHCP server and adding *.lan.mydomain.com wildcard A record to this IP. The advantage is that I can test on mobile devices easily - livereload working like magic on multiple devices. When on the road I use *.lh.mydomain.com A 127.0.0.1 instead.

If you are running into issue why dig or nslookup still doesn't work with your domain. It turns out they don't use the official system resolver on Mac OS (ref: https://stackoverflow.com/questions/50914268/os-x-etc-resolver-dev-isnt-working-why-not )

Therefore, to test a domain . Use this

dscacheutil -q host -a name argocd.ml-dev.test