DOT Manager: INFO main - Embedding is not successful

My Config file:

#The sections are strictly ordered.
#Don't remove or rearrange any section

[EmulationName]
sdnp2p_emulation

[PhysicalTopology]
#First line: Number of physical machines
#Then, each line specifies a tuple:
#type name ip cpu memory disk external_interface bandwidth
3
manager sdnp2p-OptiPlex-3020 10.0.0.2
node sdnp2p-OptiPlex-3020 10.0.0.5 4 16777216 374 br-ext 100
node sdnp2p-OptiPlex-3020 10.0.0.6 4 16777216 374 br-ext 100

[PhysicalTopologyDelay]
#Pairwise delay between any physical vms
#If no delay between a pair is specified, default value will be considered
#Default value of delay is 0
#First line: Number of pair of machines have delay
#Next, each line specifies a tuple
#machine1, machine2, delay (ms)
0

[LogicalTopology]
#First line: Number of switches, number of links
#Each switch is represented by 's#'
#Switch # should start with 1
#Next, each line specifies a bidirectional link with the following format:
# s# s# bandwidth delay
3 2 
s1 s2 499 150
s1 s3 500 100

[Images]
#Number of images
#each line image id, type, location
2
i1 tc base_tc.qcow2
i2 ubuntu base_lubuntu_mini.qcow2

[VirtualMachineProvision]
#Start marker of this section. Don't remove
Hypervisor=kvm
Library=lib-virt
NetworkFile=resources/provisioning/libvirt/libvirt_network.xml
#End marker of this section. Don't remove

[VirtualMachines]
#First line: Number of VMs
#Each switch is represented by 'h#'
#VM# should start with 1
#Next, each line specifies a VM, the switch it is attached, CPU, B/W(Mbps), Memory(MB) and image:
# VM# s# CPU B/W Memory i#
5
h1 s1 1 300 64 i1
h2 s2 2 400 512 i2
h3 s3 1 300 64 i1
h4 s1 2 400 64 i1
h5 s2 1 300 512 i2

[Controllers]
#First line: Number of controllers
#Each controller is represented by 'c#'
#Controller # should start with 1
#Next, each line a tuple:
# c# ip port
1
c1 10.0.0.2 6633

[Switch2Controller]
#First line: Number of switches
#Next, each line specifies a switch and its controller
# s# c#
3
s1 c1
s2 c1
s3 c1

[Credentials]
#User name of the dot nodes
UserName=dot 

[OtherConfig]
#
OFVersion=1.0

DOT Manager and Nodes setup successful. But I am getting: INFO main - Embedding is not successful

dothub / dot

DOT Manager: INFO main - Embedding is not successful #2