There are Carbon Autorelease Build Failures in vbd-impl:

https://jenkins.opendaylight.org/releng/view/autorelease/job/autorelease-release-carbon/55/

[ERROR] Failed to execute goal on project vbd-impl: Could not resolve dependencies for project org.opendaylight.honeycomb.vbd:vbd-impl:bundle:1.1.0-Carbon: Could not find artifact org.opendaylight.mdsal:mdsal-singleton-common-api:jar:2.1.1-Carbon in opendaylight-mirror (https://nexus.opendaylight.org/content/repositories/public/) -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/DependencyResolutionException
[ERROR]
[ERROR] After correcting the problems, you can resume the build with the command
[ERROR] mvn <goals> -rf :vbd-impl