Most firewalls will allow users inside the firewall to initiate connections outwards, so the following will not apply. For users with restrictive firewall policies that prevent outgoing connections or outgoing vnc connections, please read the following
CrossBrowserTesting.com provides the Live Test service via a VNC client to connect and display the remote browser. In your account’s settings, there are three options for browser-based VNC clients, and one option for a Desktop-based VNC client.
Ports required to be open by VNC client type:
- HTML5: Uses port 443 over HTTPS via web sockets (wss)
- Flash SSL: Uses port 443 over HTTPS via web sockets (wss)
- Flash: Tries port 80 over TCP, then tries port range 5920-6100 over TCP
- Java: Tries port 80 over TCP, then tries port range 5920-6100 over TCP
- VNC Client: Uses port range 5920-6100 over TCP
By default, traffic from a Live Test connects to
livetest.crossbrowsertesting.com. Traffic on this subdomain runs across a “high-speed network” which improves the responsiveness of your test session. However, this address resolves to changing IP addresses based on an analysis of the fastest path. Because the resolved IP address varies, it is easier to set firewall rules for a consistent IP address using our standard domain:
crossbrowsertesting.com (Please contact support for the IP address)
To set up a firewall rule with our consistent IP address, follow these steps:
- Turn off the “High-Speed Network” setting in your account settings, which will resolve our outgoing VNC connections to
crossbrowsertesting.com(See image below)
- Add a rule to your firewall allowing connections initiated from inside your network on port 80 and ports 5920-6100 to our IP (Please contact support for the IP address)
- If you are using the Flash SSL or HTML5 client you may also need to allow for port 843 and 443 outbound to
If you want to continue to use the High-Speed Network, leave the High-Speed Network setting on, and configure your firewall to allow connections initiated from inside your network on port 80, 443 and / or ports 5920-6100. Do not try to filter on destination IP address, as it will continually change.
If you are using a desktop VNC client, it will always use a port from 5920 – 6100. The Java, FLash, and HTML5 clients use port 80 or 443 to connect.
Have questions or need help on this? Call us or send an email.