最近登陆时 报错 unknown server error 怎么回事

[2017/8/29 15:12:38:608]: EMChatClientImpl::init()
[2017/8/29 15:12:38:609]: EMConfigManager::init() 
[2017/8/29 15:12:38:609]: No config file, do nothing
[2017/8/29 15:12:38:609]: addConnectionListener
[2017/8/29 15:12:38:609]: addConnectionListener
[2017/8/29 15:12:38:609]: addConnectionListener
[2017/8/29 15:12:38:611]: addConnectionListener
[2017/8/29 15:12:38:614]: registerContactListener
[2017/8/29 15:12:38:619]: restBaseUrl()
[2017/8/29 15:12:38:619]: EMDNSManager::getCurrentHost: type: 2
[2017/8/29 15:12:38:619]: EMSessionManager::checkDNS()
[2017/8/29 15:12:38:619]: valid_time: 
[2017/8/29 15:12:38:619]: no saved dns list, download it
[2017/8/29 15:12:38:619]: getDnsListFromServer()
[2017/8/29 15:12:38:619]: buildUrl(): http://rs.easemob.com/easemob/server.json?sdk_version=3.1.2&app_key=HHH&file_version=1
[2017/8/29 15:12:38:685]: current host: domain: 47.94.182.48 port: 80
[2017/8/29 15:12:54:541]: EMSessionManager::login(): 1101
[2017/8/29 15:12:54:541]: buildUrl(): https:///easemob/server.json?sdk_version=3.1.2&app_key=HHH&file_version=227
[2017/8/29 15:12:54:549]: getDnsListFromServer code: 400 response: 
[2017/8/29 15:12:54:553]: getDnsListFromServer code: 400 response: 
[2017/8/29 15:12:54:556]: getDnsListFromServer code: 400 response: 
[2017/8/29 15:12:54:556]: getDnsListFromServer failed