So first I try

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[root@geppetto ~]# cobbler check
The following are potential configuration items that you may want to fix:

1 : you need to set some SELinux rules if you want to use cobbler-web (an optional package), run the following: /usr/sbin/semanage fcontext -a -t httpd_sys_content_rw_t "/var/lib/cobbler/webui_sessions/.*"
2 : debmirror package is not installed, it will be required to manage debian deployments and repositories

Restart cobblerd and then run 'cobbler sync' to apply changes.
[root@geppetto ~]#
==================

and then I do as cobbler check suggests:

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[root@geppetto ~]# /usr/sbin/semanage fcontext -a -t httpd_sys_content_rw_t "/var/lib/cobbler/webui_sessions/.*"
/usr/sbin/semanage: Type httpd_sys_content_rw_t is invalid, must be a file or device type
[root@geppetto ~]#
==================

Any suggestions?

Thanks,
Joost