Multiple data source's/servers with one Grafana instance Bad Gateway

I’m running 2 servers:

  • server 1 is in one location with (Grafana and Influxdb) already integrated together.
  • server 2 has Influxdb running in another location couple thousand kilometers apart.

The servers can ping each other via site to site VPN, but I keep getting a 502 bad gateway error when I try to set up server two as a second data source. Can anyone help?