path: root/docs/cobbler.pod

=head1 NAME

cobbler is a provisioning and update server.  It supports deployments via PXE (network booting), virtualization (Xen or QEMU/KVM), and re-installs of existing Linux systems.  The latter two features are enabled by usage of 'koan' on the remote system.  Update server features include yum mirroring and integration of those mirrors with kickstart.  Cobbler has a command line interface, Web UI, and extensive Python and XMLRPC APIs for integration with external scripts and applications.

=head1 SYNOPSIS

cobbler command [subcommand] [--arg1=value1] [--arg2=value2]

=head1 DESCRIPTION

Cobbler manages provisioning using a tiered concept of Distributions, Profiles, Systems, and Repositories.

Distributions contain information about what kernel and initrd are used, plus metadata (required kernel parameters, etc).

Profiles associate a Distribution with a kickstart file and optionally customize the metadata further.

Systems associate a MAC, IP, and/or hostname with a distribution and optionally customize the metadata further.

Repositories contain yum mirror information.  Using cobbler to mirror repositories is an optional feature, though provisioning and package management share a lot in common.

The main advantage of cobbler is that it glues together a lot of disjoint technologies and concepts and abstracts the user from the need to understand them.   It allows the systems administrator to concentrate on what he needs to do, and not how it is done. 

This manpage will focus on the cobbler command line tool for use in configuring cobbler.  There is also mention
of the Cobbler WebUI which is usable for day-to-day operation of Cobbler once installed/configured.  Docs on
the API and XMLRPC components are available online at http://cobbler.et.redhat.com and the companion Wiki:
https://hosted.fedoraproject.org/projects/cobbler/.

Most users will be interested in the Web UI and should set it up, though the command line is needed for initial configuration -- in particular "cobbler check" and "cobbler import".

=head1 SEE ALSO

For help in building kickstarts, try using the "system-config-kickstart" tool, or install a new system and look at the /root/anaconda-ks.cfg file left over from the installer.  General kickstart questions can also be asked at kickstart-list@redhat.com.  Cobbler ships some kickstart templates in /etc/cobbler that may also prove helpful.

Also see the aforementioned webpages for additional documentation, user contributed tips, and so on.

=head1 COBBLER USAGE

=head2 SETUP

After installing, run "cobbler check" to verify that cobbler's ecosystem is configured correctly.   Cobbler check will direct you on how to modify it's config files using a text editor.

Any problems detected should be corrected, with the potential exception of DHCP related warnings where you will need to use your judgement as to whether they apply to your environment.  Run "cobbler sync" after making any changes to the configuration files to ensure those changes are applied to the environment.

It is especially important that the server name field be accurate in /var/lib/cobbler/settings, without this field being correct, kickstart trees will not be found, and automated installtions will fail.

For PXE, if DHCP is to be run from the cobbler server, the dhcp configuration file should be changed as suggested by "cobbler check".  If DHCP is not run locally, the "next-server" field on the DHCP server should at minimum point to the cobbler server's IP and the filename should be set to "pxelinux.0".  Alternatively, cobbler can also generate your dhcp configuration file if you want to run dhcp locally -- this is covered in a later section.  If you don't already have a DHCP setup managed by some other tool, allowing cobbler to manage DHCP will prove to be useful as it can manage DHCP reservations and other data.  If you already have a DHCP setup, moving an existing setup to be managed from within cobbler is relatively painless -- though usage of the DHCP management feature is entirely optional.  If you are not interested
in network booting via PXE and just want to use koan to install virtual systems or replace existing ones, DHCP configuration can be totally ignored.  Koan also has a live CD (see koan's manpage) capability that can be used to simulate PXE environments.

=head2 ADDING A DISTRIBUTION

This first step towards configurating what you want to provision is to add a distribution to the cobbler's configuration.  

If there is an rsync mirror, DVD, NFS, or filesystem tree available that you would rather import instead, skip down to the documentation about the "import" command.  It's really a lot easier, and it only requires waiting for the mirror content to be copied and/or scanned.  Imported mirrors also save time during install since they don't have to hit external install sources.

If you want to be explicit with distribution definition, however, here's how it works:

B<cobbler distro add --name=string --kernel=path --initrd=path [--kopts=string] [--ksmeta=string] [--arch=x86|x86_64|ia64] [--breed=redhat|debian|suse]>

=over

=item name

a string identifying the distribution, this should be something like "rhel4".

=item kernel

An absolute filesystem path to a kernel image

=item initrd

An absolute filesystem path to a initrd image

=item kopts

Sets kernel command-line arguments that the distro, and profiles/systems dependant
on it, will use.

Example: --kopts="foo=bar baz=3 asdf"

=item arch

Sets the architecture for the PXE bootloader

The default setting ('standard') will use pxelinux.   Set to 'ia64' to use elilo.

'x86' and 'x86_64' effectively do the same thing as standard.

=item ksmeta

This is an advanced feature that sets kickstart variables to substitute, thus enabling kickstart files to be treated as templates.  Templates are powered using Cheetah and are described further along in this manpage as well as on the Cobbler Wiki.

Example: --ksmeta="foo=bar baz=3 asdf"

See the section on "Kickstart Templating" for further information.

=item breed

Controls how kernel arguments for automatic installation are to be treated.  Defaults to "redhat", which is a suitable value for Fedora and Centos as well.  It means anything redhat based.

There is limited experimental support for specifying "debian" or "suse", which treats the kickstart file as a different format and changes the kernel
arguments appropriately.   Support for other types of distributions is possible in the future.  

The file used for the answer file, regardless of the breed setting, is the value used for --kickstart when creating the profile.  

=back

=head2 ADDING A PROFILE

A profile associates a distribution to additional specialized options, such as a kickstart automation file.  Profiles are the core unit of provisioning and at least one profile must exist for every distribution to be provisioned.  A profile might represent, for instance, a web server or desktop configuration.  In this way, profiles define a role to be performed.  

B<cobbler profile add --name=string --distro=string [--kickstart=path] [--kopts=string] [--ksmeta=string] [--virt-file-size=gigabytes] [--virt-ram=megabytes] [--virt-type=string] [--virt-cpus=integer] [--virt-path=string] [--virt-bridge=string] [--server-override]>

Arguments are as listed for distributions, save for the removal of "arch" and "breed", and with the additions listed below:

=over

=item name

A descriptive name.  This could be something like "rhel4webservers" or "fc6desktops".

=item distro

The name of a previously defined cobbler distribution

=item kickstart

Local filesystem path to a kickstart file.  http:// URLs (even CGI's) are also accepted, but a local file path is recommended, so that the kickstart templating engine can be taken advantage of.

If this parameter is not provided, the kickstart file will default to /etc/cobbler/default.ks.  This file is initially blank, meaning default kickstarts are not automated "out of the box".  Admins can change the default.ks if they desire..

When using kickstart files, they can be placed anywhere on the filesystem, but the recommended path is /var/lib/cobbler/kickstarts.


=item virt-file-size

(Virt-only) How large the disk image should be in Gigabytes.  The default is "5".
This can be a comma seperated list (ex: "5,6,7") to allow for multiple disks of different sizes
depending on what is given to --virt-path.

=item virt-ram

(Virt-only) How many megabytes of RAM to consume.  The default is 512 MB.

=item virt-type

(Virt-only) Koan can install images using either Xen paravirt ("xenpv") or QEMU/KVM ("qemu").  Choose one or the other strings to specify, or values will default to attempting to find a compatible installation type on the client system ("auto").  See the "koan" manpage for more documentation.  The default virt-type can be configured in the cobbler settings file such that this parameter does not have to be provided.

=item virt-cpus

(Virt-only) How many virtual CPUs should koan give the virtual machine?  The default is 1.

=item virt-path

(Virt-only) Where to store the virtual image on the host system.  Except for advanced cases, this parameter can usually be omitted. For disk images, the value is usually an absolute path to an existing directory with an optional file name component.  There is support for specifying partitions "/dev/sda4" or volume groups "VolGroup00", etc.

For multiple disks, seperate the values with commas such as "VolGroup00,VolGroup00" or "/dev/sda4,/dev/sda5".  Both those examples would create two disks for the VM.

=item virt-bridge

(Virt-only) This specifies the default bridge to use for all systems defined under this profile.  If not specified, it will assume the default value in the cobbler settings file, which as shipped in the RPM is 'xenbr0'.  If using KVM, this is most likely not correct.  You may want to override this setting in the system object.  Bridge settings are important as they define how outside networking will reach the guest.
For more information on bridge setup, see the Cobbler Wiki, where there is a section describing koan usage.

=item repos

This is a space delimited list of all the repos (created with "cobbler repo add" and updated with "cobbler reposync") that this profile
can make use of during kickstart installation.  For example, an example might be --repos="fc6i386updates fc6i386extras" if the profile wants to access these two mirrors that are already mirrored on the cobbler server.

=item inherit

This is an advanced feature.  

Profiles may inherit from other profiles in lieu of specifing --distro.  Inherited profiles will override any settings specified in their parent, with the exception of --ksmeta (templating) and --kopts (kernel options), which will be blended together.  

Example:  If profile A has --kopts="x=7 y=2", B inherits from A, and B has --kopts="x=9 z=2", the actual kernel options that will be used for B are "x=7 y=2 z=2". 

Example:  If profile B has --virt-ram=256 and A has --virt-ram of 512, profile B will use the value 256.  
Example:  If profile A has a --virt-file-size of 5 and B does not specify a size, B will use the value from A.

=back

=item server-override

This parameter should be useful only in select circumstances.  If machines are on a subnet that cannot access the cobbler server using the name/IP as configured in the cobbler settings file, use this parameter to override that server name.   See also --dhcp-tag for configuring the next server and DHCP informmation of the system if you are also using Cobbler to help manage your DHCP configuration.

=head2 ADDING A SYSTEM

System records map a piece of hardware (or a virtual machine) with the cobbler profile to be assigned to run on it.  This may be thought of as chosing a role for a specific system.

Note that if provisioning via koan and PXE menus alone, it is not required to create system records, though they are useful when system specific customizations are required.   One such customization would be defining the MAC address.  If there is a specific role inteded for a given machine, system records should be created for it.

B<cobbler system add --name=string --profile=string [--mac=macaddress] [--ip=ipaddress] [--hostname=hostname] [--kopts=string] [--ksmeta=string] [--kickstart=path] [--netboot-enabled=Y/N] [--server-override=string]>

Adds a cobbler System to the configuration.  Arguments are specified as per "profile add" with
the following changes:

=over

=item name

The system name works like the name option for other commands.

If the name looks like a MAC address or an IP, the name will implicitly be used for either --mac or --ip of the first interface, respectively.   However, it's usually better to give a descriptive name.

A system created with name "default" has special semantics.  If a default system object exists, it sets all undefined systems to PXE to a specific profile.  Without a "default" system name created, PXE will fall through to local boot for unconfigured systems.

=item mac

Specifying a mac address via --mac allows the system object to boot via PXE.  If the name of the cobbler system already looks like a mac address, this is inferred from the system name and does not need to be specified.  

MAC addresses have the format AA:BB:CC:DD:EE:FF.

=item ip

If cobbler is configured to generate a DHCP configuratition (see advanced section), use this
setting to define a specific IP for this system in DHCP.  Leaving off this parameter will result in no DHCP management for this particular system.

Example: ---ip=192.168.1.50

Note for Itanium users:  this setting is always required for IA64 regardless of whether DHCP management is enabled.

If DHCP management is disabled, setting this parameter may still be useful for record keeping, and it is also available in all kickstart templates, so it can be easily used for static IP configuration within kickstarts.

=item hostname

If using the DHCP configuration feature (see advanced section) with dnsmasq, use this to define a hostname for the system to recieve from DNS.  If not using DHCP management or not using dnsmasq, this field is treated as a descriptive comment and is basically ignored other than being made available in templates.

Example: --hostname=mycomputer.example.com

=item --gateway and --subnet

If you are using static IP configurations, you may find it useful to store gateway and subnet
information inside of cobbler.  These variables are not used internally by cobbler, but are
made available in cobbler templates, which are described later in this document and on the Wiki.
For DHCP configurations, these parameters should be left blank.

=item --virt-bridge

(Virt-only) While --virt-bridge is present in the profile object (see above), here it works on an interface by interface basis.   For instance it would be possible to have --virt-bridge0=xenbr0 and --virt-bridge1=xenbr1.  If not specified in cobbler for each interface, koan will use the value as specified in the profile for each interface, which may not always be what is intended, but will be sufficient in most cases. 

=item --kickstart

While it is recommended that the --kickstart parameter is only used within for the "profile add" command, there are scenarios when an install base switching to cobbler may have kickstarts created on a per-system basis (one kickstart for each system, nothing shared) and may not want to immediately make use of the cobbler templating system.  This allows specifing a kickstart for use on a per-system basis.  Creation of a parent profile is still required.  If the kickstart is a filesystem location, it will still be treated as a cobbler template.

=item --netboot-enabled

If set false, the system will be provisionable through koan but not through
standard PXE.  This will allow the system to fall back to default PXE boot behavior without deleting the cobbler system object.  The default value allows PXE.

=item --dhcp-tag

If you are setting up a PXE environment with multiple subnets/gateways, and are using cobbler to manage a DHCP configuration, you will probably want this option.

By default, the dhcp tag for all systems is "default" and means that in the DHCP template files the systems will expand out where $insert_cobbler_systems_definitions is found in the DHCP template.  However, you may want certain systems to expand out in other places in the file.  Setting --dhcp-tag=subnet2 for instance, will cause that system to expand out where $insert_cobbler_system_definitions_subnet2 is found, allowing you to insert directives to specify different subnets (or other parameters) before the DHCP configuration entries for those particular systems.

This is described further on the Cobbler Wiki.

=item --interface

By default flags like --ip, --mac, --dhcp-tag, --gateway, --subnet, and --virt-bridge operation on the first network
interface defined for a system.  Additional interfaces can be specified (0 through 7) for use with the edit command.

Example:  

cobbler system edit --name=foo --ip=192.168.1.50 --mac=AA:BB:CC:DD:EE:A0
cobbler system edit --name=foo --interface=2 --ip=192.168.1.51 --mac=AA:BB:CC:DD:EE:A1
cobbler system report foo

NOTE: Additional interfaces can presently only be deleted via the web interface.

=end

=head2 ADDING A REPOSITORY TO MIRROR

Repository mirroring allows cobbler to mirror not only install trees ("cobbler import" does this for you) but also optional packages, 3rd party content, and even updates.   Mirroring all of this content locally
on your network will result in faster, more up-to-date installations and faster updates.  If you
are only provisioning a home setup, this will probably be overkill, though it can be very useful
for larger setups (labs, datacenters, etc).

B<cobbler repo add --mirror=url --name=string [--rpmlist=list] [--creatrepo-flags=string] [--keep-updated=Y/N] [--arch=string]>

=over

=item mirror

The addresss of the yum mirror.  This can be an rsync:// URL, an ssh location, or
a http:// or ftp:// mirror location.  Filesystem paths also work.

The mirror address should specify an exact repository to mirror -- just one architecture
and just one distribution.  If you have a seperate repo to mirror for a different arch, add that
repo seperately.  

Here's an example of what looks like a good URL:

rsync://yourmirror.example.com/fedora-linux-core/updates/6/i386 (for rsync protocol)
http://mirrors.kernel.org/fedora/extras/6/i386/ (for http://)
user@yourmirror.example.com/fedora-linux-core/updates/6/i386  (for SSH)

Experimental support is also provided for mirroring RHN content when you need
a fast local mirror.  The mirror syntax for this is --mirror=rhn://channel-name and you must
have entitlements for this to work.  This requires the cobbler server to be installed on RHEL5
or later.  You will also need a version of yum-utils equal or greater to 1.0.4.

Additionally, if you are running yum 3.2.4 or later, you can also automatically
tell cobbler to mirror any yum repository that the boot server itself is
configured to use.  This command is "cobbler repo auto-add" and is also
somewhat experimental.  

=item name

This name is used as the save location for the mirror.  If the mirror represented, say, Fedora Core
6 i386 updates, a good name would be "fc6i386updates".  Again, be specific.

This name corresponds with values given to the --repos parameter of "cobbler profile add".  If a profile has a --repos value that matches the name given here, that repo can be automatically set up during provisioning (when supported) and installed systems will also use the boot server as a mirror (unless "yum_post_install_mirror" is disabled in the settings file).  By default the provisioning server
will act as a mirror to systems it installs, which may not be desirable for laptop configurations, etc.

Distros that can make use of yum repositories during kickstart include FC6 and later, RHEL 5 and later, and derivative distributions.

See the documentation on "cobbler profile add" for more information.

=item local-filename

Local filename specifies, for kickstarts containing the template parameter "yum_config_stanza",
what files to populate on provisioned clients in /etc/yum.repos.d.  

In other words, if this value is "foo", the repo would be installed on provisioned clients as "/etc/yum.repos.d/foo.repo".  

If you don't want clients to have this repo installed, don't add a name for the repo, and provisioned machines will not configure yum to know about this repo -- you can still do it manually if you choose.  The repository will still be used for installation, it just won't get installed automatically in /etc/yum.repos.d on the client.

See /etc/cobbler/kickstart_fc6.ks for an example of how to employ this within a kickstart template.

=item rpm-list

By specifying a space-delimited list of package names for --rpm-list, one can decide to mirror only a part of a repo (the list of packages given, plus dependencies).  This may be helpful in conserving time/space/bandwidth.  For instance, when mirroring FC6 Extras, it may be desired to mirror just cobbler and koan, and skip all of the game packages.  To do this, use --rpm-list="cobbler koan".

This option only works for http:// and ftp:// repositories (as it is powered by yumdownloader).  It will be ignored for other mirror types, such as local paths and rsync:// mirrors.

=item createrepo-flags

Specifies optional flags to feed into the createrepo tool, which is called when "cobbler reposync" is run for the given repository.  The defaults are '-c cache'.

=item keep-updated

Specifies that the named repository should not be updated during a normal "cobbler reposync".    The repo may still be updated by name.   See "cobbler reposync" below.

=item arch

Specifies what architecture the repository should use.  By default the current system arch (of the server) is used, which may not be desirable.  Using this to override the default arch allows mirroring of source repositories (using --arch=src).

=back

=head2 DISPLAYING CONFIGURATION ENTRIES

The following commands are usable regardless of how you are using cobbler.
"report" gives detailed configuration info. "list" just lists the names of items in the configuration.
Run these commands to check how you have cobbler configured.

B<cobbler report>

B<cobbler distro|profile|system|repo report [object-name]>

B<cobbler list>

B<cobbler distro|profile|system|repo list [object-name]>

Alternatively, you could look at the configuration files in /var/lib/cobbler to see the same information.  

=head2 DELETING CONFIGURATION ENTRIES

If you want to remove a specific object, use the remove command with the name that was used to add it.

B<cobbler distro remove --name=string>

B<cobbler profile remove --name=string>

B<cobbler system remove --name=string>

B<cobbler repo remove --name=string>

=head2 EDITING

If you want to change a particular setting without doing an "add" again, use the "edit" command, using
the same name you gave when you added the item.  Anything supplied in the parameter list will overwrite
the settings in the existing object, preserving settings not mentioned.

B<cobbler distro|profile|system|repo edit --name=string [parameterlist]>

=head2 COPYING

Objects can also be copied:

B<cobbler distro|profile|system|repo copy --name=oldname --newname=newname>

=head2 RENAMING

Objects can also be renamed, as long as other objects don't reference them.

B<cobbler distro|profile|system|repo rename --name=oldname --newname=newname>

=head2 REBUILDING CONFIGURATIONS

B<cobbler sync>

Cobbler sync is used to repair or rebuild the contents /tftpboot or /var/www/cobbler when something has changed behind the scenes.  It brings the filesystem up to date with the configuration as understood by cobbler.   

Sync should be run whenever files in /var/lib/cobbler are manually edited (which is not recommended except for the settings file) or when making changes to kickstart files.  In practice, this should not happen often, though running sync too many times does not cause any adverse effects.  

If using cobbler to manage a DHCP server (see the advanced section of this manpage), sync does need to be
run after systems are added to regenerate and reload the DHCP configuration.

=head1 EXAMPLES

=head2 IMPORT WORKFLOW

This example shows how to create a provisioning infrastructure from a distribution mirror.
Then a default PXE configuration is created, so that by default systems will PXE boot into 
a fully automated install process for that distribution.

You can use a network rsync mirror, a mounted DVD location, or a tree you have available
via a network filesystem.

B<cobbler check>

B<cobbler import --path=rsync://yourfavoritemirror.com/foo --name=anyname>

# OR 

B<cobbler import --path=/mnt/dvd --name=anyname>

# OR (using an eternal NAS box without mirroring)

B<cobbler import --path=/path/where/filer/is/mounted --name=anyname --available-as=nfs://nfs.example.org:/where/mounted/>

# wait for mirror to rsync...

B<cobbler report>

B<cobbler system add --name=default --profile=name_of_a_profile1>

B<cobbler system add --name=AA:BB:CC:DD:EE:FF --profile=name_of_a_profile2>

B<cobbler sync>

=head2 NORMAL WORKFLOW

The following example uses a local kernel and initrd file (already downloaded), and 
shows how profiles would be created using two different kickstarts -- one for a web server
configuration and one for a database server.  Then, a machine is assigned to each profile.

B<cobbler check>

B<cobbler distro add --name=rhel4u3 --kernel=/dir1/vmlinuz --initrd=/dir1/initrd.img>

B<cobbler distro add --name=fc5 --kernel=/dir2/vmlinuz --initrd=/dir2/initrd.img>

B<cobbler profile add --name=fc5webservers --distro=fc5-i386 --kickstart=/dir4/kick.ks --kopts="something_to_make_my_gfx_card_work=42,some_other_parameter=foo">

B<cobbler profile add --name=rhel4u3dbservers --distro=rhel4u3 --kickstart=/dir5/kick.ks>

B<cobbler system add --name=AA:BB:CC:DD:EE:FF --profile=fc5-webservers>

B<cobbler system add --name=AA:BB:CC:DD:EE:FE --profile=rhel4u3-dbservers>

B<cobbler report>

=head2 REPOSITORY MIRRORING WORKFLOW

The following example shows how to set up a repo mirror for two repositories, and create a profile
that will auto install those repository configurations on provisioned systems using that profile.

B<cobbler check>

# set up your cobbler distros here.

B<cobbler repo add --mirror=http://mirrors.kernel.org/fedora/core/updates/6/i386/ --name=fc6i386updates>

B<cobbler repo add --mirror=http://mirrors.kernel.org/fedora/extras/6/i386/ --name=fc6i386extras>

B<cobbler reposync>

B<cobbler profile add --name=p1 --distro=existing_distro_name --kickstart=/etc/cobbler/kickstart_fc6.ks --repos="fc6i386updates fc6i386extras">

=head2 VIRTUALIZATION

For Virt, be sure the distro uses the correct kernel (if paravirt) and follow similar steps as above, adding additional parameters as desired:

B<cobbler distro add --name=fc7virt [options...]>

Specify reasonable values for the Virt image size (in GB) and RAM requirements (in MB):

B<cobbler profile add --name=virtwebservers --distro=fc7virt --kickstart=path --virt-file-size=10 --virt-ram=512 [...]>

Define systems if desired.  koan can also provision based on the profile name.

B<cobbler system add --name=AA:BB:CC:DD:EE:FE --profile=virtwebservers [...]>

If you have just installed cobbler, be sure that the "cobblerd" service is running and that port 25151 is unblocked.

See the manpage for koan for the client side steps.

=head1 ADVANCED TOPICS

=head2 PXE MENUS

Cobbler will automatically generate PXE menus for all profiles it has defined.  Running "cobbler sync" is required to generate and update these menus. 

To access the menus, type "menu" at the "boot:" prompt while a system is PXE booting.  If nothing is typed, the network boot will default to a local boot.  If "menu" is typed, the user can then choose and provision any cobbler profile the system knows about.  

If the association between a system (MAC address) and a profile is already known, it may be more useful to just use "system add" commands and declare that relationship in cobbler; however many use cases will prefer having a PXE system, especially when provisioning is done at the same time as installing new physical machines.

If this behavior is not desired, run "cobbler system add --name=default --profile=plugh" to default all PXE booting machines to get a new copy of the profile "plugh".  To go back to the menu system, run "cobbler system remove --name=default" and then "cobbler sync" to regenerate the menus.

When using PXE menu deployment exclusively, it is not neccessary to make cobbler system records, although the two can easily be mixed.

Additionally, note that all files generated for the pxe menu configurations are templatable, so if you wish to change the color scheme or equivalent, see the files in /etc/cobbler.

=head2 KICKSTART TEMPLATING

The --ksmeta options above require more explanation.

If and only if --kickstart options reference filesystem URLs, --ksmeta allows for templating of the kickstart files to achieve advanced functions.  If the --ksmeta option for a profile read --ksmeta="foo=7 bar=llama", anywhere in the kickstart file where the string "$bar" appeared would be replaced with the string "llama".  

To apply these changes, "cobbler sync" must be run to generate custom kickstarts for each profile/system.

For NFS and HTTP kickstart URLs, the "--ksmeta" options will have no effect. This is a good reason to let
cobbler manage your kickstart files, though the URL functionality is provided for integration with legacy infrastructure, possibly including web apps that already generate kickstarts.

Templated kickstart files are processed by the templating program/package Cheetah, so anything you can do in a Cheetah template can be done to a kickstart template.  Learn more at http://www.cheetahtemplate.org/learn.html

When working with Cheetah, be sure to escape any shell macros that look like "$(this)" with something like "\$(this)" or errors may show up during the sync process.

=head2 KICKSTART SNIPPETS

Anywhere a kickstart template mentions SNIPPET::snippet_name, the file named /var/lib/cobbler/snippets/snippet_name (if present) will be included automatically in the kickstart template.  This serves as a way to recycle frequently used kickstart snippets without duplication.  Snippets can contain templating variables, and the variables will be evaluated according to the profile and/or system as one would expect.

=head2 KICKSTART VALIDATION

To check for potential errors in kickstarts, prior to installation, use "cobbler validateks".  This function will check all profile and system kickstarts for detectable errors.  Since pykickstart is not future-Anaconda-version aware, there may be some false positives.  It should be noted that "cobbler validateks" runs on the rendered kickstart output, not kickstart templates themselves.

=head2 DHCP CONFIGURATION MANAGEMENT

Cobbler can optionally help you manage DHCP and (depending on how used) DNS as it relates
to systems you wish to provision/control.  This allows cobbler to essentially maintain a database
of all of your installed systems, and be a central point of control for aspects related to setting
up those systems.

This feature is off by default and must be turned on by setting 'manage_dhcp' to 1 in
/var/lib/cobbler/settings.   Choices include ISC dhcpd (default), or DNSmasq, which can be chosen
by setting manage_dhcp_mode to 'dnsmasq'.  If you choose dnsmasq and want to revert to ISC, change
the setting to 'isc'.

Depending on your choice, cobbler will use /etc/cobbler/dhcpd.template or /etc/cobbler/dnsmasq.template as a starting point.  This file must be user edited for the user's particular networking environment.  Read the file and understand how the particular app (ISC dhcpd or dnsmasq) work before proceeding.

If you already have DHCP configuration data that you would like to preserve (say DHCP was manually configured earlier), insert the relevant portions of it into the template file, as running "cobbler sync" will overwrite your previous configuration.

In summary, if this manage_dhcp bit is enabled, the following features are enabled:

(A) pinning dhcp hostnames to MAC addresses automatically.
(B) relatively seamless mixing of Itanium and x86/x86_64 machines in a PXE environment (ISC only)
(C) assigning hostnames to MAC addresses using DNS (dnsmasq only).

These options are all enabled by using the --hostname and --ip options when using the "cobbler system add" command.

Itanium systems names also need to be assigned to a distro that was created with the "--arch=ia64" parameter. If you have Itanium systems, you must (for now) choose 'isc' for 'manage_dhcp_mode' in the /var/lib/cobbler/settings file, and are required to use --ip when creating the system object in order for those systems to PXE.

The dhcpd.conf file will be updated each time "cobbler sync" is run, and not until then, so it is important to remember to use "cobbler sync" when using this feature.

=head2 SERVICE DISCOVERY (AVAHI)

If the avahi-tools package is installed, cobblerd will broadcast it's presence on the network, allowing it to be discovered by koan with the koan --server=DISCOVER parameter.

=head2 IMPORTING TREES


Cobbler can auto-add distributions and profiles from remote sources, whether this is a filesystem path or an rsync mirror.  This can save a lot of time when setting up a new provisioning environment.  Import is a feature that many users will want to take advantage of, and is very simple to use.
  
After an import is run, cobbler will try to detect the distribution type and automatically assign kickstarts.  By default, it will provision the system by erasing the hard drive, setting up eth0 for dhcp, and using a default password of "cobbler".  If this is undesirable, edit the kickstart files in /etc/cobbler to do something else or change the kickstart setting after cobbler creates the profile.

Mirrored content is saved automatically in /var/www/cobbler/ks_mirror.

Example:  B<cobbler import --mirror=rsync://mirrorserver.example.com/path/ --name=fedora>

Example2:  B<cobbler import --mirror=root@192.168.1.10:/stuff --name=bar>

Example3:  B<cobbler import --mirror=/mnt/dvd --name=baz>

Example4:  B<cobbler import --mirror=/path/to/stuff --name=glorp>

Example5:  B<cobbler import --path=/path/where/filer/is/mounted --name=anyname --available-as=nfs://nfs.example.org:/where/mounted/>

Once imported, run a "cobbler list" or "cobbler report" to see what you've added.

By default, the rsync operations will exclude PPC content, debug RPMs, and ISO images -- to change what is excluded during an import, see /etc/cobbler/rsync.exclude.

Note that all of the import commands will mirror install tree content into /var/www/cobbler unless a network accessible location is given with --available-as.  --available-as will be primarily used when importing distros stored on an external NAS box, or potentially on another partition on the same machine that is already accessible via http:// or ftp://.

=head2 DEFAULT PXE BOOT BEHAVIOR

What happens when PXE booting a system when cobbler has no record of the system being booted?

By default, cobbler will configure PXE to boot to the contents of /etc/cobbler/default.pxe, which (if unmodified) will just fall through to the local boot process.  Administrators can modify this file if they
like to change that behavior.

An easy way to specify a default cobbler profile to PXE boot is to create a system named "default".  This will cause /etc/cobbler/default.pxe to be ignored.  To restore the previous behavior do a "cobbler system remove" on the "default" system.

B<cobbler system add --name=default --profile=boot_this>

B<cobbler system remove --name=default>

=head2 REPO MANAGEMENT

This has already been covered a good bit in the command reference section.

Yum repository management is an optional feature, and is not required to provision through cobbler.  However, if cobbler is configured to mirror certain repositories, it can then be used to associate profiles with those repositories.  Systems installed under those profiles will then be autoconfigured to use these repository mirrors in /etc/yum.repos.d, and if supported (Fedora Core 6 and later) these repositories can be leveraged even within Anaconda.  This can be useful if (A) you have a large install base, (B) you want fast installation and upgrades for your systems, or (C) have some extra software not in a standard repository but want provisioned systems to know about that repository.

Make sure there is plenty of space in cobbler's webdir, which defaults to /var/www/cobbler.

B<cobbler reposync>

Cobbler reposync is the command to use to update repos as configured with "cobbler repo add".  Mirroring
can take a long time, and usage of cobbler reposync prior to cobbler sync is needed to ensure provisioned systems have the files they need to actually use the mirrored repositories.  If you just add repos and never run "cobbler reposync", the repos will never be mirrored.  This is probably a command you would want to put on a crontab, though the frequency of that crontab and where the output goes is left up to the systems administrator.

For those familiar with yum's reposync, cobbler's reposync is (in most uses) a wrapper around the yum command.  Please use "cobbler reposync" to update cobbler mirrors, as yum's reposync does not perform all required steps.  Also cobbler adds support for rsync and SSH locations, where as yum's reposync only supports what yum supports (http/ftp).

If you ever want to update just a few repositories, and not all of them managed by cobbler, you can
run:

B<cobbler reposync reponame1 reponame2 ...>

When updating repos by name, a repo will be updated even if it is set to be not updated during a regular reposync operation (ex: cobbler repo edit --name=reponame1 --keep-updated=0).

Note that if a cobbler import provides enough information to use the boot server as a yum mirror for core packages, cobbler can set up kickstarts to use the cobbler server as a mirror instead of the outside world.  If this feature is not desirable, it can be turned on by setting yum_post_install_mirror to 0 in /var/lib/cobbler/settings (and rerunning "cobbler sync").  You should disable this feature if machines are provisioned on a different VLAN/network than production, or if you are provisioning laptops that will want to acquire updates on multiple networks.

=head2 PXE BOOT LOOP PREVENTION

If you have your machines set to PXE first in the boot order (ahead of hard drives), change the "pxe_just_once" flag in /var/lib/cobbler/settings to 1.  This will set the machines to not PXE on successive boots once they complete one install.  To re-enable PXE for a specific system, run the following command:

B<cobbler system edit --name=name --netboot-enabled=1>

=head2 KICKSTART TRACKING

Cobbler knows how to keep track of the status of kickstarting machines.   

B<cobbler status>

Using the status command will show when cobbler thinks a machine started kickstarting and when it last requested a file.  This is a good way to track machines that may have gone interactive during kickstarts.  Cobbler will also make a special request in the post section of the kickstart to signal when a machine is finished kickstarting.

To use this feature, the kickstart tree files need to be served via a http://server/cblr/... URL, which happens automatically when using the "cobbler import" command to pull in a kickstart tree from an rsync mirror.

If kickstart trees are somewhere else, one can still benefit from the kickstart tracking feature by adding a symlink to /var/www/cobbler/localmirror/distroname will allow the kickstarts to be served through the tracking URL mentioned above.   Be sure to use the http://server/cblr/ URL to point to the kickstart tree for each distro you want to track.

Note that kickstart tracking support using syslog requires an Anaconda that supports syslog forwarding.  RHEL5 is good, as is FC6 and later.  URL tracking currently requires python2.3 or higher on the server for the mod_python piece to work.  This will likely be improved later to better support older distros acting as a cobbler server.

=head2 TWEAKING

Enterprising users can edit the files in /var/lib/cobbler directly versus using the command line.  The repair mechanism for user error here is to delete the files in /var/lib/cobbler.  There are also a few configuration files in /etc/cobbler that can be edited.

Running "cobbler sync" is required to apply any changes that are made manually.

=head2 TRIGGERS

Triggers provide a way to integrate cobbler with arbitrary 3rd party software without modifying cobbler's code.  When adding a distro, profile, system, or repo, all scripts in /var/lib/cobbler/triggers/add are executed for the particular object type.  Each particular file must be executable and it is executed with the name of the item being added as a parameter.  Deletions work similarly -- delete triggers live in /var/lib/cobbler/triggers/delete.  Order of execution is arbitrary, and cobbler does not ship with any triggers by default.

=head2 API

Cobbler also makes itself available as a Python API for use by higher level management software.  Learn more at http://cobbler.et.redhat.com

=head2 WEB USER INTERFACE

Most of the day-to-day actions in cobbler's command line can be performed in Cobbler's Web UI.  To enable and access the WebUI, perform the following steps.

1) Set xmlrpc_rw_enabled to 1 in /var/lib/cobbler/settings to enable network control.

2) Change the admin xmlrpc secret in /etc/cobbler/auth.conf.  You won't have to remember it. 

3) The default Web UI password is "cobbler/ILoveCobbler", to change this, run:

htdigest /var/www/cgi-bin/cobbler/.htpasswd "Cobbler WebUI Authentication" cobbler

4) SELinux users may also have to run:

setsebool httpd_can_network_connect true

chcon httpd_sys_content_t /etc/cobbler/auth.conf

5) Run /sbin/service cobblerd restart.  

6) Visit http://yourserver.example.org/cgi-bin/cobbler/webui.cgi and log in with whatever you chose in step 3.

=head1 EXIT_STATUS

cobbler's command line returns a zero for success and non-zero for failure.

=head1 ADDITIONAL RESOURCES

Cobbler has a mailing list for user and development-related questions/comments at et-mgmt-tools@redhat.com.  

IRC channel:  irc.freenode.net (#cobbler)

Official web site: http://cobbler.et.redhat.com/

Wiki and user contributed content: https://hosted.fedoraproject.org/projects/cobbler/

=head1 AUTHOR

Michael DeHaan <mdehaan@redhat.com>