README
¶
lresolver
lresolver is a simple local DNS resolver. It try to solve a very specific problem when you need to deal with more than one internal DNS server.
Some features:
- Load balancing using round-robin
- Try to resolve on all servers (in parallel, if not found on first attempt)
- No limit on the number of DNS servers
- In-memory cache
Credits
This projects uses the great DNS library miekg/dns by Miek Gieben. The first version of this code was based on StalkR/dns-reverse-proxy.
Install & Config
Download the static binary here: lresolver/releases.
To complie from sources (you need Go installed):
go get github.com/lucindo/lresolver
Configuration
The supported formats for configuration are: YAML, JSON, TOML and HCL. On starting up lresolver will try to find the file lresolver.{yml,yaml,json,toml,hcl} in /etc/lresolver/ or in the current directory. You can also specify the configuration file with the -config flag.
Configuration directives:
| Directive | Required | Default | Description |
|---|---|---|---|
bind |
Yes | - | Address to bind the server, e.g 127.0.0.1 |
nameservers |
Yes | - | List of DNS servers |
cache |
No | true |
Turn on/off internal caching |
negative_cache |
No | true |
Cache non-NOERROR responses |
max_cache_ttl |
No | 300 |
Internal cache TTL in seconds |
tcp |
No | true |
Listen to TCP as well |
Sample Configuration:
bind: 127.0.0.1
cache: true
negative_cache: true
max_cache_ttl: 300
tcp: true
nameservers:
- 8.8.8.8
- 8.8.4.4
Running
Point /etc/resolv.conf to 127.0.0.1:
# /etc/resolv.conf
nameserver 127.0.0.1
You can leave your other resolv.conf directives (search, domain, etc) unchanged.
In my production systems I put the lresolver.yml in /etc/lresolver/ directory and run the server this way:
/sbin/lresolver -log_dir /var/log/lresolver/
You can clear the cache by sending an USR1 signal to the running server.
To Do
- Update expired entries in background
- Packages for popular Linux distros (deb and rpm)
- Statistics on requests and nameservers
- Option to replace round-robin to dynamic weighted round-robin based on server's response time
- External configuration on
etcd - Suffix-based request routing
- Automatic configuration reload
Contributing
- Fork it
- Create your feature branch:
git checkout -b my-awesome-new-feature - Commit your changes:
git commit -m 'Add some awesome feature' - Push to the branch:
git push origin my-awesome-new-feature - Submit a pull request
Documentation
¶
There is no documentation for this package.
Source Files