buildbot exception in on ofbiz-trunk

[buildbot]

The Buildbot has detected a build exception on builder ofbiz-trunk while building . Full details are available at:
    https://ci.apache.org/builders/ofbiz-trunk/builds/1215

Buildbot URL: https://ci.apache.org/

Buildslave for this Build: silvanus_ubuntu

Build Reason: The AnyBranchScheduler scheduler named 'on-ofbiz-commit' triggered this build
Build Source Stamp: [branch ofbiz/trunk] 1756310
Blamelist: taher

BUILD FAILED: exception shell upload_2

Sincerely,
 -The Buildbot