Docker swarm can't work, it can't show cluster infomation

when I use docker run --rm swarm create ,it return a 503 error
this is the error:
`

503 Service Unavailable


No server is available to handle this request. ` and when I use my old token to create cluster, I use`docker -H tcp://192.168.31.202:2376 info` it can't show any nodes. the manage container's logs: time="2017-04-24T00:46:09Z" level=error msg="Discovery error: Failed to fetch entries, Discovery service returned 503 HTTP status code" does the server meet some problems?