The Operations Manager agent will initiate a connection over port 5723 to the management server, pulling down configuration data and those management pack rules which apply to this agent and sending back both heartbeat and performance data.
Once a firewall connection has been opened one way then communication between the 2 hosts can be initiated freely bi-directionally.
But if there is no established connection and one side tries to *initiate* communication…..that will be blocked by the firewall if you don’t have rules going both ways allowing bi-directional communication.
Component A Port Number and direction Component B
RMS 1433—> Ops DB
MS 1433–> Ops DB
MS 5723–> RMS
Web Console Server 5724–> RMS
Web Console Browser 51908–> Web Console Server
Agent 5723–> RMS
Agent 5723–> MS
Reports Server 1433–> Data Warehouse