Mackerel Support About monitoring Monitoring operations Is it possible to control which port the mackerel-agent uses? While it's not possible to control the port, we do support connection via proxy. For more information please refer to the section "I want to connect via HTTP Proxy." in the agent specs. Related articles Is it possible to monitor network devices? The agent won’t startup. What environments are supported by Mackerel? What is the source IP address for Webhook and other services’ alert notifications from Mackerel? Mackerel doesn't recognize duplicate servers from agent installed templates ／ machine images etc.