PBI refreshes work when connected to internal network, and some refreshes work only on external netw

[Anonymous]

Hi,

I have two on-prem gateways which I have set up for two different workspaces (e.g. workspace A and workspace B). Workspace A's on -prem gateway works when connected to internal network, and workspace B's on-prem gateway works when connected to the external network. What is the reason behind this? and if we were to keep both gateways running at the same time, would we need to set up two different pc's, on connected to internal network, and one connected to external network?

Another question which I have and would like to understand is that the pbix file for workspace B can refresh only when connected to external network. What is the reason for this?