SAP Knowledge Base Article - Public

2395995 - Boomi DC2 Atom Server Error: HTTP transport error: Connection Refused


Outbound communications from Boomi atom server in DC2 is being blocked by SuccessFactors Firewall and throws below error:

"Connection refused"

 Conneciton Refused.JPG




Outbound communication from DC2 atom server is allowed only on standard port 443 for HTTPS protocol and 80 for HTTP protocol.

If after adding into allow list on DC2 atom server IP address also, your calls are failing do check if communication is allowed on port 443/80 from your end as we support only these 2 ports due to security reason.

Apart from this, if any other port is being used then create a CS Support incident with below information:

  • Source IP or hostname( Boomi atom server)
  • Destination IP or hostname
  • Port being used for communication
  • Time frame (for which the connectivity is required or permanent)
  • Valid business justification of using non standard port


Allow list IP Address Connection Refused , KBA , LOD-SF-INT-BPI , Dell & Boomi Infrastructure , LOD-SF-INT , Integrations , Problem


SAP SuccessFactors HXM Core all versions