In the file networkInterface.md we have

N/A: No connection to node, or no cache.

Source of the issue:

support-core-plugin/src/main/java/com/cloudbees/jenkins/support/impl/NetworkInterfaces.java:[122,56]

getIndex() is not public in java.net.NetworkInterface; cannot be accessed from outside package

java.net.NetworkInterface#getIndex() is Java 7+

Several issues :

• https://jenkins.ci.cloudbees.com/job/plugins/job/support-core-plugin is building with J7
• animal sniffer is configured to check with java 5 ... but it isn't called by default

If we remove this line the file is correctly generated