umbra example fails at begin

[nimaafraz]

After installation the load, install, and start work fine but begin fails:

nimaafraz@umbra-1:~/umbra/examples$ python3 fabric/local-2orgs.py


		############ umbra-design ################
	 Experiment saved at /tmp/umbra/fabric/local-2orgs.json
	 Experiment settings in  /tmp/umbra/fabric/local-2orgs
		############ umbra-design ################


nimaafraz@umbra-1:~/umbra/examples$ umbra-cli --uuid umbra-cli --address 127.0.0.1:9988 --debug --source /tmp/umbra/fabric/local-2orgs

		<<< Welcome to Umbra >>>

:umbra> load /tmp/umbra/fabric/local-2orgs.json

-> task: Loading configuration file at /tmp/umbra/fabric/local-2orgs.json
-> result: Configuration loaded

:umbra> install

: Installing :

-> task: Installing Umbra at environment umbra-default
-> result: Install Umbra in environment umbra-default Ok

:umbra> start

: Starting :

-> task: Starting component 'umbra-broker' in environment umbra-default
-> result: Started component 'umbra-broker' in environment umbra-default Ok


-> task: Starting component 'umbra-monitor' in environment umbra-default
-> result: Started component 'umbra-monitor' in environment umbra-default Ok


-> task: Starting component 'umbra-scenario' in environment umbra-default
-> result: Started component 'umbra-scenario' in environment umbra-default Ok

:umbra> begin

: Beginning :

-> task: Experiment Begin
-> error: Umbra Experiment Error