Typically it is not uncommon to use yours hosts file to redirect network traffic on your local machine to point to your local environment where appropriate. That works pretty well for most circumstances however it can become a little tiresome if you are managing a large number of projects and quickly your hosts file can become quite long and unwieldy.
One alternative to using your hosts file is to use a local dns server. One such option is DNSMasq.
dnsmasq is free software providing Domain Name System (DNS) caching, a Dynamic Host Configuration Protocol (DHCP) server, router advertisement and network boot features, intended for small computer networks.
dnsmasq has low requirements for system resources, can run on Linux, BSDs, Android and macOS, and is included in most Linux distributions. Consequently, it "is present in a lot of home routers and certain Internet of Things gadgets" and is included in Android.
Choosing a Domain suffix
There are a plethora of domain suffixes available. For many years I used .dev tld for local development. I have also seen the use of .com and .co.uk etc, However as .dev is now a tld owned by Google and is treated much like any other tld domain by browsers. Since 2017 Firefox and Chrome force the use of https by default on these top level domains , which will mean that you will have an additional step of setting up a self signed certificate in order to work in these browsers, a common requirement for most web development teams these days as part of the software development lifecycle and release process is to check how a new feature or bug fix will perform in these browsers and resolve any issues etc before being released.
- .example - Not installed as a domain name, but usable in text as an example. example.com, example.net and example.org are also reserved for this purpose but are active sites.
- .invalid - Not installed as a domain name, but usable in testing as a domain which wouldn't work.
- .local Local network
- .localhost Points back to own computer
- .onion Connection to the Tor network
- .test Meant for testing DNS
That said said when setting up a domain name locally why ot just use one that is reserved or owned by someone already. I use:
So what I plan to do is show the steps for setting up and configuring DNS masq locall on a Mac. One of the easiest ways is to install on the Mac is with Home Brew:
# Update your homebrew installation brew up # Install dnsmasq brew install dnsmasq
Setting up DNSMasq
As the instructions suggest, do the following.
$ mkdir -p /usr/local/etc/ $ cp /usr/local/opt/dnsmasq/dnsmasq.conf.example /usr/local/etc/dnsmasq.conf
Setup Dnsmasq to auto start on reboot.
$ sudo cp -fv /usr/local/opt/dnsmasq/*.plist /Library/LaunchDaemons $ sudo chown root /Library/LaunchDaemons/homebrew.mxcl.dnsmasq.plist
Start Dnsmasq now and accept the warning.
$ sudo launchctl load /Library/LaunchDaemons/homebrew.mxcl.dnsmasq.plist
The following commands show how to stop and start Dnsmasq. This must be done after any configuration changes are made.
$ sudo launchctl unload /Library/LaunchDaemons/homebrew.mxcl.dnsmasq.plist $ sudo launchctl load /Library/LaunchDaemons/homebrew.mxcl.dnsmasq.plist
Now that you have Dnsmasq installed and running, it’s time to configure it! The configuration file lives at
/usr/local/etc/dnsmasq.conf by default, so open this file in your favourite editor.
One the many, many things that Dnsmasq can do is compare DNS requests against a database of patterns and use these to determine the correct response. I use this functionality to match any request which ends in
.internal and send
127.0.0.1 in response. The Dnsmasq configuration directive to do this is very simple:
Insert this into your
/usr/local/etc/dnsmasq.conf file (I put it near the example
address=/double-click.net/127.0.0.1 entry just to keep them all together) and save the file.
You may need to restart Dnsmasq to get it to recognise this change. Restarting Dnsmasq is the same as any other service running under
sudo launchctl stop homebrew.mxcl.dnsmasq sudo launchctl start homebrew.mxcl.dnsmasq
You can test Dnsmasq by sending it a DNS query using the domain internet groper utility aka as dig. Pick a name ending in
internal (or whatever your preference) and use dig to query your new DNS server:
dig testing.testing.one.two.three.internal @127.0.0.1
You should get back a response something like:
;; ANSWER SECTION: testing.testing.one.two.three.internal. 0 IN A 127.0.0.1
Configuring OS X
Now that you have a working DNS server you can configure your operating system to use it. There are two approaches to this:
Send all DNS queries to Dnsmasq.
.internalqueries to Dnsmasq.
The first approach is easy – just change your DNS settings in System Preferences. I.e. set 127.0.0.1 as a DNS server
There is Another Way
It is worth knowing that there is an alternative way to configure DNSMasq.
The second approach involves editing
/etc/resolv.conf which controls the way DNS queries are performed, including the default server to use for DNS queries (this is the setting that gets set automatically when you connect to a network or change your DNS server/s in System Preferences).
# # macOS Notice # # This file is not consulted for DNS hostname resolution, address # resolution, or the DNS query routing mechanism used by most # processes on this system. # # To view the DNS configuration used by this system, use: # scutil --dns # # SEE ALSO # dns-sd(1), scutil(8) # # This file is automatically generated. # nameserver 184.108.40.206 nameserver 220.127.116.11 nameserver 10.230.56.145 nameserver 172.16.161.22
Here we can see that the /etc/resolv.conf matches the entries from the system control panel.
Mac OS 10.15 also allows you to configure additional resolvers by creating configuration files in the
/etc/resolver/ directory. This directory probably won’t exist on your system, so your first step should be to create it:
sudo mkdir -p /etc/resolver
Now you should create a new file in this directory for each resolver you want to configure. Each resolver corresponds – roughly and for our purposes – to a top-level domain like our
dev. There a number of details you can configure for each resolver but I generally only bother with two:
- the name of the resolver (which corresponds to the domain name to be resolved); and
- the DNS server to be used.
$ ls -al total 64 drwxr-xr-x@ 10 root wheel 320 24 Oct 2019 . drwxr-xr-x 151 root wheel 4832 18 Nov 23:58 .. -rw-r--r-- 1 root wheel 21 24 Oct 2019 digital -rw-r--r--@ 1 root wheel 21 26 Apr 2018 internal -rw-r--r-- 1 root wheel 21 24 Oct 2019 local -rw-r--r-- 1 root wheel 21 24 Oct 2019 local2 -rw-r--r-- 1 root wheel 21 24 Oct 2019 localhost -rw-r--r--@ 1 root wheel 21 28 Sep 2018 test -rw-r--r--@ 1 root wheel 21 26 Apr 2018 vbox
each one of these entries looks like this
To create a new file with the same name as your new top-level domain (I’m using
dev, recall) in the
/etc/resolver/ directory and add a
nameserver to it by running the following commands:
sudo tee /etc/resolver/internal >/dev/null <<EOF nameserver 127.0.0.1 EOF
internal is the top-level domain name that I’ve configured Dnsmasq to respond to and
127.0.0.1 is the IP address of the server to use.
Once you’ve created this file, OS X will automatically read it and you’re done. My /usr/local/etc/dnsmasq.conf file looks like this
listen-address=127.0.0.1 address=/.internal/127.0.0.1 address=/.localhost/127.0.0.1 address=/.local/127.0.0.1 address=/.dev/127.0.0.1 # keep nameserver order of resolv.conf strict-order conf-file=/Users/danlobo/.config/valet/dnsmasq.conf
Testing you new configuration is easy; just use ping check that you can now resolve some DNS names in your new top-level domain.
ping -c 1 www.duckduckgo.com # Check that .internal names work ping -c 1 this.is.a.test.internal ping -c 1 iam.the.walrus.internal
You should see results that mention the IP address in your Dnsmasq configuration like this:
PING iam.the.walrus.internal (127.0.0.1): 56 data bytes
You can now just make up new DNS names under
.internal whenever you please and they will automatically route to localhost if there is something to point to, i.e. a virtual machine