I'm trying to build master using just the repositories defined in the source tree. (ie: not using a local nexus proxy)

The first stoppage happens in OpenNMS Tests Mock SNMP Agent with:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-assembly-plugin:2.4:single (make-assembly) on project org.opennms.tests.mock-snmp-agent: Failed to create assembly: Unable to resolve dependencies for assembly 'jar-with-dependencies': Failed to resolve dependencies for assembly: Unable to get dependency information for org.apache.servicemix.specs:org.apache.servicemix.specs.jaxb-api-2.2:jar:2.2.0: Failed to process POM for org.apache.servicemix.specs:org.apache.servicemix.specs.jaxb-api-2.2:jar:2.2.0: Non-resolvable parent POM for org.apache.servicemix:servicemix-pom:5: Could not find artifact org.apache:apache:pom:7 in servicemix (http://maven.opennms.org/content/groups/servicemix-release/)
[ERROR] org.apache.servicemix.specs:org.apache.servicemix.specs.jaxb-api-2.2:jar:2.2.0

If you start the build again, it continues on until OpenNMS Core Library (XML).

[ERROR] Failed to execute goal on project org.opennms.core.xml: Could not resolve dependencies for project org.opennms.core:org.opennms.core.xml:bundle:1.13.1-SNAPSHOT: Failure to find oro:oro:jar
:2.0.8 in http://maven.opennms.org/content/groups/opennms.org-release was cached in the local repository, resolution will not be reattempted until the update interval of opennms-repo has elapsed or updates are forced -> [Help 1]

If you start the build again, it continues on until OpenNMS Features Jmx Config Generator Web UI.

[ERROR] Failed to execute goal on project jmxconfiggenerator.webui: Could not resolve dependencies for project org.opennms.features:jmxconfiggenerator.webui:bundle:1.13.1-SNAPSHOT: Could not find artifact org.twitter4j:twitter4j-core:jar:3.0.6 -> [Help 1]

If you start the build again, it continues on unitl OpenNMS Features Node Maps

[ERROR] Failed to execute goal on project vaadin-node-maps: Could not resolve dependencies for project org.opennms.features:vaadin-node-maps:bundle:1.13.1-SNAPSHOT: Could not find artifact com.goo
gle.gwt:gwt-dev:jar:2.5.1 in vaadin-addons (http://maven.opennms.org/content/groups/vaadin.com-addons/) -> [Help 1]

If you start the build again, it continues on unitl OpenNMS OSGi Container - OpenNMS Features

[ERROR] Failed to execute goal org.opennms.maven.plugins:features-maven-plugin:1.0.2-SNAPSHOT:generate-features-xml (features.xml) on project all: Execution features.xml of goal org.opennms.maven.plugins:features-maven-plugin:1.0.2-SNAPSHOT:generate-features-xml failed: javax.xml.bind.UnmarshalException: unexpected element (uri:"http://karaf.apache.org/xmlns/features/v1.0.0", local:"html"). Expected elements are <{http://karaf.apache.org/xmlns/features/v1.0.0}features> -> [Help 1]

I did a strace on the process and found that it was failing at this point because it was trying to download from osgi.sonatype.org (See https://ops4j1.jira.com/browse/PAXURL-151 for whats happening there.)
After adding "-Dorg.ops4j.pax.url.mvn.useFallbackRepositories=false", it fails with:

[ERROR] Failed to execute goal org.opennms.maven.plugins:features-maven-plugin:1.0.2-SNAPSHOT:generate-features-xml (features.xml) on project all: Execution features.xml of goal org.opennms.maven.plugins:features-maven-plugin:1.0.2-SNAPSHOT:generate-features-xml failed: URL mvn:org.apache.activemq/activemq-karaf/5.6.0/xml/features could not be resolved. -> [Help 1]

At this point, I haven't been able to figure out how to fix this issue, so a build won't complete.