The IPFire DBL is published as a Response Policy Zone (RPZ) and can be consumed by many popular recursive DNS resolvers.
Resolvers fetch the list via AXFR/IXFR, store it locally, and only
transfer updates when the zone changes — keeping bandwidth usage
low and resolution fast.
The primary to fetch the zones from is hosted at
primary.dbl.ipfire.org and TLS is available.
If your DNS software does not allow to fetch the lists using AXFR/IXFR, a HTTPS download is also available as a fallback.