在执行cobbler check时出现下列错误

[root@cobbler ~]# cobbler check
httpd does not appear to be running and proxying cobbler, or SELinux is in the way. Original traceback:
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/cobbler/cli.py", line 252, in check_setup
    s.ping()
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1199, in __call__
    return self.__send(self.__name, args)
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1489, in __request
    verbose=self.__verbose
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1243, in request
    headers
ProtocolError: <ProtocolError for 127.0.0.1:80/cobbler_api: 503 Service Temporarily Unavailable>

解决方法：

[root@cobbler ~]# getenforce
Enforcing
[root@cobbler ~]# setenforce 0
[root@cobbler ~]# getenforce
Permissive
[root@cobbler ~]# service httpd restart
Stopping httpd:                                            [  OK  ]
Starting httpd:                                              [  OK  ]

重新执行该命令

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

1 : The 'server' field in /etc/cobbler/settings must be set to something other than localhost, or kickstarting features will not work.  This should be a resolvable hostname or IP for the boot server as reachable by all machines that will use it.
2 : For PXE to be functional, the 'next_server' field in /etc/cobbler/settings must be set to something other than 127.0.0.1, and should match the IP of the boot server on the PXE network.
3 : SELinux is enabled. Please review the following wiki page for details on ensuring cobbler works correctly in your SELinux environment:
    https://github.com/cobbler/cobbler/wiki/Selinux
4 : some network boot-loaders are missing from /var/lib/cobbler/loaders, you may run 'cobbler get-loaders' to download them, or, if you only want to handle x86/x86_64 netbooting, you may ensure that you have installed a *recent* version of the syslinux package installed and can ignore this message entirely.  Files in this directory, should you want to support all architectures, should include pxelinux.0, menu.c32, elilo.efi, and yaboot. The 'cobbler get-loaders' command is the easiest way to resolve these requirements.
5 : change 'disable' to 'no' in /etc/xinetd.d/rsync
6 : since iptables may be running, ensure 69, 80/443, and 25151 are unblocked
7 : comment out 'dists' on /etc/debmirror.conf for proper debian support
8 : comment out 'arches' on /etc/debmirror.conf for proper debian support
9 : The default password used by the sample templates for newly installed machines (default_password_crypted in /etc/cobbler/settings) is still set to 'cobbler' and should be changed, try: "openssl passwd -1 -salt 'random-phrase-here' 'your-password-here'" to generate new one

Restart cobblerd and then run 'cobbler sync' to apply changes.

 问题解决