Troubleshooting
This section covers some questions that frequently come up in IRC, some of which are problems, and some of which are things about Cobbler that are not really problems, but are things folks just ask questions about frequently.
Have you run Cobbler check? What did it say? Is Cobbler and koan at
the most recent released stable version? Is cobblerd
running? Have
you tried restarting it if this is a recent upgrade or config
change? If something isn't showing up, have you restarted cobblerd
and run cobbler sync
after making changes to the config file? If
you can't connect or retrieve certain files, is Apache running, or
have you restarted it after a new install? If there's a koan
connectivity problem, are there any firewalls blocking port 25150?
Trick question! one does not run cobbler import
on repos :)
Install trees contain more data than repositories. Install trees
are for OS installation and are added using cobbler import
or
cobbler distro add
if you want do something more low level.
Repositories are for things like updates and additional packages.
Use cobbler repo add
to add these sources. If you accidentally
import a repo URL (for instance using rsync), clean up
/var/www/cobbler/ks\_mirror/name\_you\_used
to take care of it.
Cobbler can't detect what you are importing in advance before you
copy it. Thankfully man cobbler
gives plenty of good examples for
each command, cobbler import
and cobbler repo add
and gives
example URLs and syntaxes for both.
These are not actually kickstart files, they are kickstart file templates.
You can, but you need to escape any dollar signs ($) with (\$) so
the Cobbler templating engine doesn't eat them. This is not too
hard, use cobbler profile getks
and cobbler system getks
to
make sure everything renders correctly. Also #raw ... #endraw in
Cheetah can be useful.
If it's not related to Cobbler's kickstart templating engine, and it's more of "how do I do this in pre/post", kickstart-list is excellent.
http://www.redhat.com/mailman/listinfo/kickstart-list
Otherwise, you are likely seeing a Cheetah syntax error. Learn more about Cheetah syntax at http://cheetahtemplate.org/learn for further information.
This can be a problem. Adding a CNAME for your Cobbler server that is accessible everywhere, such as "cobbler", or even "boot" can save a lot of characters over hostname.xyz.acme-corp.internal.org. It will show up twice in the kernel options line, once for the kickstart URL, and once for the kickstart URL. Save characters by not using FQDNs when possible. The IP may also be shorter in some cases. Cobbler should try to remove optional kernel args in the event of overflow (like syslog) but you still need to be careful.
(Newer kernels are supposed to not have this limit)
I'm getting PXE timeouts and my Cobbler server is also a virtualized host and I'm using dnsmasq for DHCP
Libvirtd starts an instance of dnsmasq unrelated to the DHCP needed for Cobbler to PXE -- it's just there for local networking but can cause conflicts. If you want PXE to work, do not run libvirtd on the Cobbler server, or use ISC dhcpd instead. You can of course run libvirtd on any other guests in your management network, and if you don't need PXE support, running libvirtd on the Cobbler server is also fine.
Alternatively you can configure your DHCP server not to listen on all interfaces: dnsmasq run by libvirtd is configured to listen on internal virbr0/192.168.122.1 only. For ISC dhcpd you can set in /etc/sysconfig/dhcpd:
DHCPDARGS=eth0
For dnsmasq you can set in /etc/dnsmasq.conf:
interface=eth0
except-interface=lo
bind-interfaces
See the Anaconda network troubleshooting page: http://fedoraproject.org/wiki/Anaconda/NetworkIssues
This URL has "Fedora" in it, but applies equally to Red Hat and derivative distributions.
cobblerd
won't start and say:
Starting cobbler daemon: Traceback (most recent call last):
File "/usr/bin/cobblerd", line 76, in main
api = cobbler_api.BootAPI(is_cobblerd=True)
File "/usr/lib/python2.6/site-packages/cobbler/api.py", line 127, in __init__
module_loader.load_modules()
File "/usr/lib/python2.6/site-packages/cobbler/module_loader.py", line 62, in load_modules
blip = __import__("modules.%s" % ( modname), globals(), locals(), [modname])
File "/usr/lib/python2.6/site-packages/cobbler/modules/authn_pam.py", line 53, in <module>
from ctypes import CDLL, POINTER, Structure, CFUNCTYPE, cast, pointer, sizeof
File "/usr/lib64/python2.6/ctypes/__init__.py", line 546, in <module>
CFUNCTYPE(c_int)(lambda: None)
MemoryError
Check your SELinux settings. Immediate fix is to disable selinux:
setenforce 0
There are two types of installer kernel/initrd pairs. There's a
normal one (for all physical installations) and a Xen paravirt one.
If you cobbler import
an install tree (say from a DVD image) and
get some "xen" distributions, these distributions will then not
show up in your PXE menu -- just because Cobbler knows it's
impossible to PXE boot them on physical hardware.
If you want to install virtual guests, read "man koan" for details.
If you want to install a physical host, use the standard distribution, the one without "xen" in the name. Instead, in the "%packages" section of the kickstart, add the package named "kernel-xen".
This only applies for Xen, of course, if you are using KVM, it's simpler and there is only one installer kernel/initrd pair to worry about -- the main one.
In recent versions of Fedora, the Xen kernels have merged again, so this is not a problem.
If you use virt-type xenpv, make sure the profile you are installing uses a distro with "xen" in the name. These are the paravirtualized versions of the installer kernel/initrd pair.
Make sure your host arch matches your guest arch
If installing Xen and using virsh console or xm console, if you
don't use --nogfx
at one point the installer will appear to hang.
Most likely it did not, it switched over to using VNC which you can
view with virt-manager. If you would like to keep using the text
console, use --nogfx
instead. This does not apply to other virt
types, only Xen.
There really aren't any KVM gotchas, other than making sure
/dev/kvm
is present (you need the right kernel module installed on
the host) otherwise things will install with qemu and appear to be
very slow.
libvir: Xen error : Domain not found: xenUnifiedDomainLookupByUUID
libvir: Xen error : Domain not found: xenUnifiedDomainLookupByName
If you see the above, it's not an error. These strange messages are perfectly normal and are coming from Xen as it's looking for an existing domain. It does not come from Cobbler/Koan and your installation will not be affected. We agree they are confusing but they are not coming from Cobbler or Koan.
If you setup Cobbler all correctly and you are trying to network book with PXE and you receive this error right after the VirtualBox POST:
`FATAL: No bootable medium found! System halted.`
Be sure to install to install the VirtualBox Extensions Pack to enable PXE boot support.
Website: https://cobbler.github.io - Dokumentation: https://cobbler.readthedocs.io