fabirc的get或者put抛出的paramiko.ssh_exception.SSHException: Channel closed.

内容抛出错误如下

Traceback (most recent call last):
  File "/Library/Python/2.7/site-packages/fabric/main.py", line 743, in main
    *args, **kwargs
  File "/Library/Python/2.7/site-packages/fabric/tasks.py", line 368, in execute
    multiprocessing
  File "/Library/Python/2.7/site-packages/fabric/tasks.py", line 264, in _execute
    return task.run(*args, **kwargs)
  File "/Library/Python/2.7/site-packages/fabric/tasks.py", line 171, in run
    return self.wrapped(*args, **kwargs)
  File "/Library/Python/2.7/site-packages/fabric/decorators.py", line 53, in inner_decorator
    return func(*args, **kwargs)
  File "/Users/sunchao/oe_dev/fabfile.py", line 227, in uat_down
    get('~/xxx.dump', '~/')
  File "/Library/Python/2.7/site-packages/fabric/network.py", line 639, in host_prompting_wrapper
    return func(*args, **kwargs)
  File "/Library/Python/2.