I unzipped openhab-online-2.0.0.b2.zip into an empty directory and run start.sh on a Mac, and it logs:
2016-02-02 00:11:08.455 [INFO ] [.openhab.core.internal.CoreActivator] - openHAB runtime has been started (v2.0.0, build b2).
2016-02-02 00:11:36.402 [WARN ] [url.mvn.internal.AetherBasedResolver] - Error resolving artifactorg.openhab.persistence:org.openhab.persistence.rrd4j:jar:1.9.0.b2:Could not find artifact org.openhab.persistence:org.openhab.persistence.rrd4j:jar:1.9.0.b2 in oh-releases-repo (https://jcenter.bintray.com/)
shaded.org.eclipse.aether.resolution.ArtifactResolutionException: Could not find artifact org.openhab.persistence:org.openhab.persistence.rrd4j:jar:1.9.0.b2 in oh-releases-repo (https://jcenter.bintray.com/)
at shaded.org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:444)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifacts(DefaultArtifactResolver.java:246)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifact(DefaultArtifactResolver.java:223)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.internal.impl.DefaultRepositorySystem.resolveArtifact(DefaultRepositorySystem.java:294)[4:org.ops4j.pax.url.mvn:2.4.3]
at org.ops4j.pax.url.mvn.internal.AetherBasedResolver.resolve(AetherBasedResolver.java:573)[4:org.ops4j.pax.url.mvn:2.4.3]
at org.ops4j.pax.url.mvn.internal.AetherBasedResolver.resolve(AetherBasedResolver.java:528)[4:org.ops4j.pax.url.mvn:2.4.3]
at org.ops4j.pax.url.mvn.internal.AetherBasedResolver.resolve(AetherBasedResolver.java:506)[4:org.ops4j.pax.url.mvn:2.4.3]
at org.ops4j.pax.url.mvn.internal.AetherBasedResolver.resolve(AetherBasedResolver.java:481)[4:org.ops4j.pax.url.mvn:2.4.3]
at org.apache.karaf.features.internal.download.impl.MavenDownloadTask.download(MavenDownloadTask.java:34)[9:org.apache.karaf.features.core:4.0.3]
at org.apache.karaf.features.internal.download.impl.AbstractRetryableDownloadTask.run(AbstractRetryableDownloadTask.java:58)[9:org.apache.karaf.features.core:4.0.3]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)[:1.8.0_31]
at java.util.concurrent.FutureTask.run(FutureTask.java:266)[:1.8.0_31]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)[:1.8.0_31]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)[:1.8.0_31]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)[:1.8.0_31]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)[:1.8.0_31]
at java.lang.Thread.run(Thread.java:745)[:1.8.0_31]
Caused by: shaded.org.eclipse.aether.transfer.ArtifactNotFoundException: Could not find artifact org.openhab.persistence:org.openhab.persistence.rrd4j:jar:1.9.0.b2 in oh-releases-repo (https://jcenter.bintray.com/)
at shaded.org.eclipse.aether.connector.basic.ArtifactTransportListener.transferFailed(ArtifactTransportListener.java:39)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.connector.basic.BasicRepositoryConnector$TaskRunner.run(BasicRepositoryConnector.java:355)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.util.concurrency.RunnableErrorForwarder$1.run(RunnableErrorForwarder.java:67)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.connector.basic.BasicRepositoryConnector$DirectExecutor.execute(BasicRepositoryConnector.java:581)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.connector.basic.BasicRepositoryConnector.get(BasicRepositoryConnector.java:249)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.internal.impl.DefaultArtifactResolver.performDownloads(DefaultArtifactResolver.java:520)[4:org.ops4j.pax.url.mvn:2.4.3]
at shaded.org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:421)[4:org.ops4j.pax.url.mvn:2.4.3]
... 16 more
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