This is a bug in the Maven site plugin. The Maven site plugin for various reasons will only ever look for dependencies in what it thinks is Maven central.
Therefore you either have to:
- Have a
<mirror>
element that proxies central through your own Nexus server. - In your local Maven repository, find the parent
pom
artifact area. Edit its_maven.repositories
file so that any mention of the repository name itself is replaced with an empty string.
I chose the latter option. After this the build runs fine.