Here below is the list of services along with the ports that needs to be accommodated on the respective FW to allow the communication 

Services and ports on spacewalk
===============================
69: TFTP (PXE provisioning)
80: Spacewalk Web interface
443: Spacewalk Web interface (SSL)
4545: Spacewalk monitoring
5222: If you plan to push actions to client systems
5269: If you push actions to a Spacewalk proxy server
9055: Oracle XE Web access