I am trying to run an Anaplan Connect script, but my firewall is not letting the traffic through. What port do I need to open?
443 is the listening port, so it doesn’t need to be opened on the client side. Communication goes out on a port (pseudo)randomly chosen by the network card, and returns on the same port. Technically, no ports need to be opened on the firewall, as long as outbound connections are permitted there shouldn't be any issue. If there is an issue, be sure that the api subdomain is whitelisted by the firewall and proxy (if applicable).
I'd recommend using a wildcard, if possible, to whitelist all Anaplan subdomains (i.e. *.anaplan.com), or whitelist api.anaplan.com:443.
In order for Anaplan Connect to work, the server it's running on needs to be able to access api.anaplan.com over port 443. You can configure your firewall to allow this traffic.