In a host which is not connected to Internet, there is a local nexus mirror which has all the necessary artifacts for a build. settings.xml file specify this host as a mirror of everything and mvn compile completes successfully. When reaching the package phase (where wildfly-swarm-plugin is used), it seems that the mirrorOf element is ignored and it tries to access repository.jboss.org and fails with a connection timeout.
This is probably an aether bug, but I also suspect https://github.com/wildfly-swarm/wildfly-swarm/blob/master/plugin/src/main/java/org/wildfly/swarm/plugin/maven/MavenArtifactResolvingHelper.java which hardcodes the repository in the constructor (I don't know if this is relevant).
Could someone with a broader view in the topic can take a look into this ?