Stuck at starting mattermost-preview

Hello, I am using mattermost-preview with docker. I don’t know why I can’t start it. It always stuck at “Checking for security update from Mattermost”.

[2017/07/13 03:35:12 UTC] [INFO] Loaded system translations for 'en' from '/mm/mattermost/i18n/en.json'
[2017/07/13 03:35:12 UTC] [INFO] Current version is 3.10.0 (3.10.0-rc1/Wed Jun  7 17:03:34 UTC 2017/f859b5f7afb391e0ae02dd69a6657574d14ece9a/none)
[2017/07/13 03:35:12 UTC] [INFO] Enterprise Enabled: false
[2017/07/13 03:35:12 UTC] [INFO] Current working directory is /mm/mattermost
[2017/07/13 03:35:12 UTC] [INFO] Loaded config file from /mm/mattermost/config/config_docker.json
[2017/07/13 03:35:12 UTC] [INFO] Server is initializing...
[2017/07/13 03:35:12 UTC] [INFO] Pinging SQL master database
[2017/07/13 03:35:16 UTC] [INFO] The database schema has been set to version 3.10.0
[2017/07/13 03:35:28 UTC] [DEBG] Deleting any unused pre-release features
[2017/07/13 03:35:29 UTC] [DEBG] Initializing user API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing team API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing channel API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing post API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing file API routes
[2017/07/13 03:35:29 UTC] [DEBG] api.system.init.debug
[2017/07/13 03:35:29 UTC] [DEBG] Initializing webhook API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing preference API routes
[2017/07/13 03:35:29 UTC] [DEBG] api.saml.init.debug
[2017/07/13 03:35:29 UTC] [DEBG] Initializing compliance API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing cluster API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing LDAP API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing brand API routes
[2017/07/13 03:35:29 UTC] [INFO] Initializing job API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing command API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing status API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing web socket API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing emoji API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing OAuth API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing reactions api routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing WebRTC API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing open graph protocol api routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing user API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing team API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing channel API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing post API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing web socket API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing file API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing command API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing admin API routes.
[2017/07/13 03:35:29 UTC] [DEBG] Initializing general API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing OAuth API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing webhook API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing preference API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing license API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing emoji API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing status API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing WebRTC API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing reactions api routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing deprecated API routes
[2017/07/13 03:35:29 UTC] [DEBG] Parsing server templates at /mm/mattermost/templates/
[2017/07/13 03:35:29 UTC] [DEBG] Initializing user WebSocket API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing system WebSocket API routes
[2017/07/13 03:35:29 UTC] [DEBG] Initializing status WebSocket API routes
[2017/07/13 03:35:29 UTC] [DEBG] wsapi.webtrc.init.debug
[2017/07/13 03:35:29 UTC] [INFO] Starting 4 websocket hubs
[2017/07/13 03:35:29 UTC] [DEBG] Initializing web routes
[2017/07/13 03:35:29 UTC] [DEBG] Using client directory at /mm/mattermost/webapp/dist/
[2017/07/13 03:35:29 UTC] [DEBG] Hub for index 0 is starting with goroutine 2036
[2017/07/13 03:35:29 UTC] [DEBG] Hub for index 1 is starting with goroutine 2037
[2017/07/13 03:35:29 UTC] [DEBG] Hub for index 2 is starting with goroutine 2038
[2017/07/13 03:35:29 UTC] [DEBG] Hub for index 3 is starting with goroutine 2039
[2017/07/13 03:35:29 UTC] [INFO] Starting Server...
[2017/07/13 03:35:29 UTC] [INFO] Server is listening on :8065
[2017/07/13 03:35:29 UTC] [INFO] Starting jobs
[2017/07/13 03:35:29 UTC] [DEBG] Cleaning up token store.
[2017/07/13 03:35:29 UTC] [DEBG] Checking for security update from Mattermost

The log output looks ok. What happens when you go to http://<hostname or IP>:8065 ?

I’ve got connection refused. I’ve tried with web browser and curl and got the same result
curl: (7) Failed to connect to 172.17.0.1 port 8065: Connection refused

What are your firewall settings? Does your firewall allow connections on port 8065?