d3 is a set of executables written in C++ that provide easily usable utilities to manage self-hosted services that are stuck behind the ISP’s dynamic IP whims.
Note, that d3 is not actually a daemon.
The executables are designed to be reusable across different IP resolvers and DNS providers, although as of right now, only one of each is implemented. (The ones I use.)
From this you can gleam that the two category of tools provided are resolvers and DNS providers. The job of the former is to figure out what the current IP address of the machine/system is. The latter has two subcategories: the lookup tools and updaters. The lookup tools are mostly an easier to handle version of nslookup/dig that is intended to be used with other tools of the d3 suite.
Each of the tools have their own documentation:
- d3-resolve
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Resolve the current IP address and pass it over to a process on STDIN.
- d3-query
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Query A and AAAA DNS records.
- d3-filter
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Filter input lines based on record types and grouped domains.
- d3-update
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Update DNS records using a selectable backend.
The following dependencies are used by d3:
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libcurl
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nlohman’s json library (this is bundled)
You will need to provide the required development libraries and headers for these libraries.
Other than that, the following also need to be available on your system for building d3:
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A POSIX compatible make(1) implementation. If you believe your make(1) is POSIX compliant, yet building fails, please file an issue.
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Perl v5.38 or above. If you use mise, a mise.toml is provided to ensure a correct version is used.
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File::Which CPAN (Perl) package.
After acquiring all Dependencies, building d3 should be easily the following:
make [-j<n>] (1) [doas|sudo] make install [PREFIX=/opt/my/path] (2)
-
This step configures and builds d3 on your system. To perform parallel compilation the -j<n> flag may be passed to make, if your make(1) supports it.
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If you wish to install d3 on your system as well, also run this step. You may optionally need to prefix it with
doas(orsudo) to elevate make’s privileges or set aPREFIXfor a custom installation directory (default is /usr/local).
An example runit service using execline and snooze to check for required updates every hour and update a Cloudflare DNS entry if your IP has changed is the following:
#!/usr/bin/execlineb -P
export D3_CF_TOKEN my-token (1)
fdmove -c 2 1
exec snooze -H*
d3-resolve
d3-query -d my.domain.com
d3-filter
d3-update -b cloudflare-
If you are concerned for storing the token here, you can easily make this more complex to not do that.
For licenses of relied upon external libraries see the docs/licensing.adoc file.
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