Wildcard Local Domains: hosts File Limits & dnsmasq

**The hosts file cannot do wildcards, a line like 127.0.0.1 *.myapp.test will not work. The hosts file matches exact** hostnames only, so every subdomain must be listed on its own line. When you need *.myapp.test (any subdomain) to resolve locally, use dnsmasq, a lightweight DNS resolver that supports wildcard rules.

Why the hosts file has no wildcards

The hosts file is a flat lookup table: one IP, one or more exact names per line. There is no pattern matching, so *, regexes, and ranges are ignored. For a few known subdomains, just list them:

127.0.0.1 myapp.test api.myapp.test admin.myapp.test

See the hosts file syntax guide for the exact format. This breaks down only when subdomains are dynamic or too many to maintain.

Wildcard local domains with dnsmasq

dnsmasq resolves a domain and all its subdomains with one rule.

macOS (Homebrew)

brew install dnsmasq
echo 'address=/myapp.test/127.0.0.1' >> $(brew --prefix)/etc/dnsmasq.conf
sudo brew services start dnsmasq

Then tell macOS to send .test lookups to dnsmasq:

sudo mkdir -p /etc/resolver
echo 'nameserver 127.0.0.1' | sudo tee /etc/resolver/test

Now anything.myapp.test resolves to 127.0.0.1 without editing the hosts file.

Linux

sudo apt install dnsmasq
echo 'address=/myapp.test/127.0.0.1' | sudo tee /etc/dnsmasq.d/myapp.conf
sudo systemctl restart dnsmasq

On systemd-resolved setups, ensure dnsmasq is the resolver for .test or point /etc/resolv.conf accordingly, then flush DNS on Linux.

Verify it works

dig foo.myapp.test @127.0.0.1
ping bar.myapp.test

Both should resolve to 127.0.0.1. Pick a safe TLD first, see which TLD to use for local development.

hosts file vs dnsmasq: which to use

• A few fixed subdomains: the hosts file is simpler and needs no service.
• Dynamic or many subdomains: dnsmasq with a wildcard rule.

For everyday fixed mappings, Sleezr manages hosts entries with safe toggles and automatic DNS flushing, so you only reach for dnsmasq when you genuinely need wildcards.

_Last tested: June 2026 on macOS and Ubuntu 24.04._

Sources and further reading

• dnsmasq documentation
• How DNS works (Cloudflare Learning)
• The hosts file explained (Wikipedia)