If you're unable to access Dropbox through the Smoothwall Filter and Firewall, you need to configure access through the Firewall and Filter.
Dropbox doesn't support SNI and won't work through a transparent HTTPS Proxy. When installing, the Dropbox installer doesn't perform consistently with proxies.
Firewall Configuration
You need to make sure that you allow direct access outbound on port 443 temporarily. You can do this with a port rule configuration. Allow the following network ports for these IP addresses, see our help topic, Adding new Firewall rules:
Network Ports:
- HTTP = TCP 80
- HTTPS = TCP 443
IP Networks used by the Dropbox service:
- 199.47.216.0/22
- 207.171.160.0/19
- 66.228.118.0/24
- 50.16.0.0/14
Filter Configuration
- As Dropbox doesn't support NTLM, add an authentication exception for dropbox.com. See our help topic, Creating authentication exceptions.
Tip: It is best to terminate the program, set up your Authentication exception, and restart the program. If you are using SSL Login, this should not be a problem although you will need to ensure that your users have logged in to authenticate their browsing session. - Create an Allow web filter policy for the Dropbox domains listed in this article https://www.dropbox.com/en/help/217. See our help topic, Creating web filter policies.
- Move this policy above any file and image hosting block policies you may have in the Web filter policies table, as Dropbox is part of these categories. See our help topic, Managing web filter policies.
Dropbox Application Configuration
You need to set your proxy settings manually in the application by right clicking on the Dropbox icon on the top right task bar once installed.
Note: If you are using Dropbox for PC and the proxy connection fails, the application reverts to using a direct connection.