Hi there,
 
We are using latest version of XCP on 6 hosts. While issuing
VM.start or VM.start_on xmlrpc functional call , it says :
 
 
{'Status': 'Failure', 'ErrorDescription':
['SESSION_INVALID', 'OpaqueRef:cfb6df14-387d-40a1-cc27-d5962cba7712']}
 
However if I put VM.start in a loop maybe after  20-30
tries it succeeds . 
But VM.start_on does not succeed even after 70 tries.
One more observation -  VM.clone succeeds after 7-8
tries 
VM.hard_shutdown works fine 
 
Can you guide me on this issue,
Akshay