Reproduced on spacewalk-java-2.3.8-155. Creating kickstart profiles for RHEL 6 and RHEL 7 generated kickstart file containing http://<fqdn>/rhn/kickstart/... URLs. PXE boot using these kickstarts failed, as the URL was invalid and kickstart couldn't be downloaded. Upgraded to spacewalk-java-2.3.8-157 and created a new set of kickstart profiles. PXE provisioning passed successfully this time both for RHEL6 and RHEL7. Old profiles weren't "fixed" automatically, so if user created a profile and was hit by this bug, it is necessary to either fix the profile manually (meaning update the "url" option on Advanced Options page), or create a new one from the scratch. VERIFIED
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHBA-2017-0236.html