6.3. Automatic Windows installation with Cobbler

One of the challenges for creating your own Windows network installation scenario with Cobbler is preparing the necessary files in a Linux environment. However, generating the necessary binaries can be greatly simplified by using the Cobbler post trigger on the sync command. Below is an example of such a trigger, which prepares the necessary files for legacy BIOS mode boot. Boot to UEFI Mode with iPXE is simpler and can be implemented by replacing the first 2 steps and several others with creating an iPXE boot menu.

Trigger sync_post_wingen.py:

  • some of the files are created from standard ones (pxeboot.n12, bootmgr.exe) by directly replacing one string with another directly in the binary

  • in the process of changing the bootmgr.exe file, the checksum of the PE file will change and it needs to be recalculated. The trigger does this with python-pefile

  • python3-hivex is used to modify Windows boot configuration data (BCD). For pxelinux distro boot_loader in BCD, paths to winpe.wim and boot.sdi are generated as /images/<distro_name>, and for iPXE with wimboot - \Boot.

  • uses wimlib-tools to replace startnet.cmd startup script in WIM image

Windows answer files (autounattended.xml) are generated using Cobbler templates, with all of its conditional code generation capabilities, depending on the Windows version, architecture (32 or 64 bit), installation profile, etc.

startup scripts for WIM images (startnet.cmd) and a script that is launched after OS installation (post_install.cmd) are also generated from templates

Post-installation actions such as installing additional software, etc., are performed using the Automatic Installation Template (win.ks).

A logically automatic network installation of Windows 7 and newer can be represented as follows:

PXE + Legacy BIOS Boot

Original files: pxeboot.n12 → bootmgr.exe → BCD → winpe.wim → startnet.cmd → autounattended.xml
Cobbler profile 1: pxeboot.001 → boot001.exe → 001 → wi001.wim → startnet.cmd → autounatten001.xml → post_install.cmd profile_name
...

iPXE + UEFI Boot

Original files: ipxe-x86_64.efi → wimboot → bootmgr.exe → BCD → winpe.wim → startnet.cmd → autounattended.xml
Cobbler profile 1: ipxe-x86_64.efi → wimboot → bootmgr.exe → 001 → wi001.wim → startnet.cmd → autounatten001.xml → post_install.cmd profile_name
...

For older versions (Windows XP, 2003) + RIS:

Original files: pxeboot.n12 → setupldr.exe → winnt.sif → post_install.cmd profile_name
Cobbler profile <xxx>: pxeboot.<xxx> → setup<xxx>.exe → wi<xxx>.sif → post_install.cmd profile_name

6.3.1. Additional Windows metadata

Additional metadata for preparing Windows boot files can be passed through the --autoinstall-meta option for distro, profile or system.

The source files for Windows boot files should be located in the /var/www/cobbler/distro_mirror/<distro_name>/Boot directory. The trigger copies them to /var/lib/tftpboot/images/<distro_name> with the new names specified in the metadata and and changes their contents. The resulting files will be available via tftp and http.

The sync_post_wingen trigger uses the following set of metadata:

  • kernel

    kernel in autoinstall-meta is only used if the boot kernel is pxeboot.n12 (--kernel=/path_to_kernel/pxeboot.n12 in distro). In this case, the trigger copies the pxeboot.n12 file into a file with a new name and replaces:

    • bootmgr.exe substring in it with the value passed through the bootmgr metadata key in case of using Microsoft ADK/WAIK.

    • NTLDR substring in it with the value passed through the bootmgr metadata key in case of using Legacy RIS. Value of the kernel key in autoinstall-meta will be the actual first boot file.

    If --kernel=/path_to_kernel/wimboot is in distro, then kernel key is not used in autoinstall-meta.

  • bootmgr

    The bootmgr key value is passed the name of the second boot file in the Windows boot chain. The source file to create it can be:

    • bootmgr.exe in case of using Micrisoft ADK/WAIK

    • setupldr.exe for Legacy RIS

    Trigger copies the corresponding source file to a file with the name given by this key and replaces in it:

    • substring \Boot\BCD to \Boot\<bcd_value>, where <bcd_value> is the metadata bcd key value for Microsoft ADK/WAIK.

    • substring winnt.sif with the value passed through the answerfile metadata key in case of using Legacy RIS.

  • bcd

    This key is used to pass the value of the BCD file name in case of using Micrisoft ADK/WAIK. Any BCD file from the Windows distribution can be used as a source for this file. The trigger copies it, then removes all boot information from the copy and adds new data from the initrd value of the distro and the value passed through the winpe metadata key.

  • winpe

    This metadata key allows you to specify the name of the WinPE image. The image is copied by the cp utility trigger with the --reflink=auto option, which allows to reduce copying time and the size of the disk space on CoW file systems. In the copy of the file, the tribger changes the /Windows/System32/startnet.cmd script to the script generated from the startnet.template template.

  • answerfile

    This is the name of the answer file for the Windows installation. This file is generated from the answerfile.template template and is used in:

    • startnet.cmd to start WinPE installation

    • the file name is written to the binary file setupldr.exe for RIS

  • post_install_script

    This is the name of the script to run immediately after the Windows installation completes. The script is specified in the Windows answer file. All the necessary completing the installation actions can be performed directly in this script, or it can be used to get and start additional steps from http://<server>/cblr/svc/op/autoinstall/<profile|system>/name. To make this script available after the installation is complete, the trigger creates it in /var/www/cobbler/distro_mirror/<distro_name>/$OEM$/$1 from the post_inst_cmd.template template.

The following metadata does not specify boot file names and is an example of using metadata to generate files from Cobbler templates.

  • clean_disk

    The presence of this key in the metadata (regardless of its value) leads to the preliminary deletion of all data and the disk partition table before installing the OS. Used in the answerfile.template and also in startnet.template in Windows XP and Windows 2003 Server installations using WinPE.

6.3.2. Preparing for an unattended network installation of Windows

  • dnf install python3-pefile python3-hivex wimlib-utils

  • enable Windows support in settings /etc/cobbler/settings.yaml:

    windows_enabled: true

  • If you have file 5.37 or newer installed (openSUSE Tumbleweed, Debian 11, RHEL/Rocky Linux 9, Fedora 37) you can easily import the Wibdows distro:

    cobbler import --name="Win10_EN-x64" --path="/mnt"

    This command will determine the version and architecture of the Windows distribution, will extract the necessary boot files from the distribution and create a distro and profile named Win10_EN-x64.

    For openSUSE Leap, Debian 10, RHEL/Rocky Linux 8 you need copy files from /mnt to /var/www/cobbler/distro_mirror/Win10_EN-x64 and create a distro and profile with the cobbler add distro/profile commands.

  • For customization winpe.win you need

    • ADK for Windows 10 / 8.1

Start -> Apps -> Windows Kits -> Deployment and Imaging Tools Environment

or

  • WAIK for Windows 7

Start -> All Programs -> Microsoft Windows AIK -> Deployment Tools Command Prompt

copype.cmd <amd64|x86|arm> c:\winpe

After executing the command, the WinPE image will be located in .\winpe.wim for WAIK and in media\sources\boot.wim for ADK. You can use either it or replace it with the one that has been obtained as a result of the import of the Windows distribution.

  • If necessary, add drivers to the image

Example:

dism /mount-wim /wimfile:media\sources\boot.wim /index:1 /mountdir:mount
dism /image:mount /add-driver /driver:D:\NetKVM\w10\amd64
dism /image:mount /add-driver /driver:D:\viostor\w10\amd64
dism /unmount-wim /mountdir:mount /commit

  • Copy the resulting WiNPE image from Windows to the boot directory of the distro

  • Share /var/www/cobbler/distro_mirror via Samba:

vi /etc/samba/smb.conf
        [DISTRO]
        path = /var/www/cobbler/distro_mirror
        guest ok = yes
        browseable = yes
        public = yes
        writeable = no
        printable = no

  • You can use tftpd.rules to indicate the actual locations of the bootmgr.exe and BCD files generated by the trigger.

cp /usr/lib/systemd/system/tftp.service /etc/systemd/system

Replace the line in the /etc/systemd/system/tftp.service

ExecStart=/usr/sbin/in.tftpd -s /var/lib/tftpboot
    to:
ExecStart=/usr/sbin/in.tftpd -m /etc/tftpd.rules -s /var/lib/tftpboot

Create a file /etc/tftpd.rules:

vi /etc/tftpd.rules
rg  \\                                      / # Convert backslashes to slashes
r   (wine.\.sif)                            /WinXp_EN-i386/\1
r   (xple.)                                 /WinXp_EN-i386/\1

r   (wi2k.\.sif)                            /Win2k3-Server_EN-x64/\1
r   (w2k3.)                                 /Win2k3-Server_EN-x64/\1

r   (boot7e.\.exe)                          /images/Win7_EN-x64/\1
r   (/Boot/)(7E.)                           /images/Win7_EN-x64/\2

r   (boot28.\.exe)                          /images/Win2k8-Server_EN-x64/\1
r   (/Boot/)(28.)                           /images/Win2k8-Server_EN-x64/\2

r   (boot9r.\.exe)                          /images/Win2019-Server_EN-x64/\1
r   (/Boot/)(9r.)                           /images/Win2019-Server_EN-x64/\2

r   (boot6e.\.exe)                          /images/Win2016-Server_EN-x64/\1
r   (/Boot/)(6e.)                           /images/Win2016-Server_EN-x64/\2

r   (boot2e.\.exe)                          /images/Win2012-Server_EN-x64/\1
r   (/Boot/)(2e.)                           /images/Win2012-Server_EN-x64/\2

r   (boot81.\.exe)                          /images/Win8_EN-x64/\1
r   (/Boot/)(B8.)                           /images/Win8_EN-x64/\2

r   (boot1e.\.exe)                          /images/Win10_EN-x64/\1
r   (/Boot/)(1E.)                           /images/Win10_EN-x64/\2

r   (.*)(/WinXp...-i386/)(.*)               /images\2\L\3
r   (.*)(/Win2k3-Server_EN-x64/)(.*)        /images\2\L\3

r   (.*)(bootxea.exe)                       /images/WinXp_EN-i386/\2
r   (.*)(XEa)                               /images/WinXp_EN-i386/\2

r   (.*)(boot3ea.exe)                       /images/Win2k3-Server_EN-x64/\2
r   (.*)(3Ea)                               /images/Win2k3-Server_EN-x64/\2

6.3.3. Final steps

  • Restart the services:

systemctl daemon-reload
systemctl restart tftp
systemctl restart smb
systemctl restart nmb

  • add additional distros for PXE boot:

cobbler distro add --name=Win10_EN-x64 \
--kernel=/var/www/cobbler/distro_mirror/Win10_EN-x64/boot/pxeboot.n12 \
--initrd=/var/www/cobbler/distro_mirror/Win10_EN-x64/boot/boot.sdi \
--arch=x86_64 --breed=windows --os-version=10

or for iPXE:

cobbler distro add --name=Win10_EN-x64 \
--kernel=/var/lib/tftpboot/wimboot \
--initrd=/var/www/cobbler/distro_mirror/Win10_EN-x64/boot/boot.sdi \
--remote-boot-kernel=http://@@http_server@@/cobbler/images/@@distro_name@@/wimboot \
--remote-boot-initrd=http://@@http_server@@/cobbler/images/@@distro_name@@/boot.sdi \
--arch=x86_64 --breed=windows --os-version=10 \
--boot-loaders=ipxe

  • and additional profiles for PXE boot:

cobbler profile add --name=Win10_EN-x64 --distro=Win10_EN-x64 --autoinstall=win.ks \
--autoinstall-meta='kernel=win10a.0 bootmgr=boot1ea.exe bcd=1Ea winpe=winpe.wim answerfile=autounattended.xml'

cobbler profile add --name=Win10-profile1 --parent=Win10_EN-x64 \
--autoinstall-meta='kernel=win10b.0 bootmgr=boot1eb.exe bcd=1Eb winpe=winp1.wim answerfile=autounattende1.xml'

cobbler profile add --name=Win10-profile2 --parent=Win10_EN-x64 \
--autoinstall-meta='kernel=win10c.0 bootmgr=boot1ec.exe bcd=1Ec winpe=winp2.wim answerfile=autounattende2.xml'

The boot menu will look like this:

LABEL Win10_EN-x64
        MENU LABEL Win10_EN-x64
        kernel /images/Win10_EN-x64/win10a.0
LABEL Win10_EN-x64-profile1
        MENU LABEL Win10_EN-x64-profile1
        kernel /images/Win10_EN-x64/win10b.0
LABEL Win10_EN-x64-profile1
        MENU LABEL Win10_EN-x64-profile2
        kernel /images/Win10_EN-x64/win10c.0

or for iPXE:

cobbler profile add --name=Win10_EN-x64 --distro=Win10_EN-x64 --autoinstall=win.ks \
--autoinstall-meta='bootmgr=boot1ea.exe bcd=1Ea winpe=winpe.wim answerfile=autounattended.xml' \
--boot-loaders=ipxe

cobbler profile add --name=Win10-profile1 --parent=Win10_EN-x64 \
--autoinstall-meta='bootmgr=boot1eb.exe bcd=1Eb winpe=winp1.wim answerfile=autounattende1.xml' \
--boot-loaders=ipxe

cobbler profile add --name=Win10-profile2 --parent=Win10_EN-x64 \
--autoinstall-meta='bootmgr=boot1ec.exe bcd=1Ec winpe=winp2.wim answerfile=autounattende2.xml' \
--boot-loaders=ipxe

The boot menu will look like this:

:Win10_EN-x64
kernel http://<http_server>/cobbler/images/Win10_EN-x64/wimboot
initrd --name boot.sdi http://<http_server>/cobbler/images/Win10_EN-x64/boot.sdi boot.sdi
initrd --name bootmgr.exe http://<http_server>/cobbler/images/Win10_EN-x64/boot1ea.exe bootmgr.exe
initrd --name bcd http://<http_server>/cobbler/images/Win10_EN-x64/1Ea bcd
initrd --name winpe.wim http://<http_server>/cobbler/images/Win10_EN-x64/winpe.wim winpe.wim
boot

:Win10_EN-x64-profile1
kernel http://<http_server>/cobbler/images/Win10_EN-x64/wimboot
initrd --name boot.sdi http://<http_server>/cobbler/images/Win10_EN-x64/boot.sdi boot.sdi
initrd --name bootmgr.exe http://<http_server>/cobbler/images/Win10_EN-x64/boot1eb.exe bootmgr.exe
initrd --name bcd http://<http_server>/cobbler/images/Win10_EN-x64/1Eb bcd
initrd --name winpe.wim http://<http_server>/cobbler/images/Win10_EN-x64/winp1.wim winpe.wim
boot

:Win10_EN-x64-profile2
kernel http://<http_server>/cobbler/images/Win10_EN-x64/wimboot
initrd --name boot.sdi http://<http_server>/cobbler/images/Win10_EN-x64/boot.sdi boot.sdi
initrd --name bootmgr.exe http://<http_server>/cobbler/images/Win10_EN-x64/boot1ec.exe bootmgr.exe
initrd --name bcd http://<http_server>/cobbler/images/Win10_EN-x64/1Ec bcd
initrd --name winpe.wim http://<http_server>/cobbler/images/Win10_EN-x64/winp2.wim winpe.wim
boot

  • cobbler sync

    • kernel from autoinstall-meta of profile or from kernel of distro property will be copied to /var/lib/tftpboot/<distro_name>

    • if the kernel is pxeboot.n12, then the bootmgr.exe substring is replaced in the copied copy of kernel with the value passed via bootmgr of the autoinstall-meta profile property

  • Install Windows

6.3.4. Legacy Windows XP and Windows 2003 Server

  • WinPE 3.0 and winboot can be used to install legacy versions of Windows. startnet.template contains the code for starting such an installation via winnt32.exe.

    • copy bootmgr.exe, bcd, boot.sdi from Windows 7 and winpe.wim from WAIK to the /var/www/cobbler/distro_mirror/WinXp_EN-i386/boot

cobbler distro add --name=WinXp_EN-i386 \
--kernel=/var/lib/tftpboot/wimboot \
--initrd=/var/www/cobbler/distro_mirror/WinXp_EN-i386/boot/boot.sdi \
--remote-boot-kernel=http://@@http_server@@/cobbler/images/@@distro_name@@/wimboot \
--remote-boot-initrd=http://@@http_server@@/cobbler/images/@@distro_name@@/boot.sdi \
--arch=i386 --breed=windows --os-version=XP \
--boot-loaders=ipxe --autoinstall-meta='clean_disk'

cobbler distro add --name=Win2k3-Server_EN-x64 \
--kernel=/var/lib/tftpboot/wimboot \
--initrd=/var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/boot/boot.sdi \
--remote-boot-kernel=http://@@http_server@@/cobbler/images/@@distro_name@@/wimboot \
--remote-boot-initrd=http://@@http_server@@/cobbler/images/@@distro_name@@/boot.sdi \
--arch=x86_64 --breed=windows --os-version=2003 \
--boot-loaders=ipxe --autoinstall-meta='clean_disk'

cobbler profile add --name=WinXp_EN-i386 --distro=WinXp_EN-i386 --autoinstall=win.ks \
--autoinstall-meta='bootmgr=bootxea.exe bcd=XEa winpe=winpe.wim answerfile=wine0.sif post_install_script=post_install.cmd'

cobbler profile add --name=Win2k3-Server_EN-x64 --distro=Win2k3-Server_EN-x64 --autoinstall=win.ks \
--autoinstall-meta='bootmgr=boot3ea.exe bcd=3Ea winpe=winpe.wim answerfile=wi2k3.sif post_install_script=post_install.cmd'

  • WinPE 3.0 without winboot also can be used to install legacy versions of Windows.

    • copy pxeboot.n12, bootmgr.exe, bcd, boot.sdi from Windows 7 and winpe.wim from WAIK to the /var/www/cobbler/distro_mirror/WinXp_EN-i386/boot

cobbler distro add --name=WinXp_EN-i386 \
--kernel=/var/www/cobbler/distro_mirror/WinXp_EN-i386/boot/pxeboot.n12 \
--initrd=/var/www/cobbler/distro_mirror/WinXp_EN-i386/boot/boot.sdi \
--arch=i386 --breed=windows --os-version=XP \
--autoinstall-meta='clean_disk'

cobbler distro add --name=Win2k3-Server_EN-x64 \
--kernel=/var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/boot/pxeboot.n12 \
--initrd=/var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/boot/boot.sdi \
--arch=x86_64 --breed=windows --os-version=2003 \
--autoinstall-meta='clean_disk'

cobbler profile add --name=WinXp_EN-i386 --distro=WinXp_EN-i386 --autoinstall=win.ks \
--autoinstall-meta='kernel=wine0.0 bootmgr=bootxea.exe bcd=XEa winpe=winpe.wim answerfile=wine0.sif post_install_script=post_install.cmd'

cobbler profile add --name=Win2k3-Server_EN-x64 --distro=Win2k3-Server_EN-x64 --autoinstall=win.ks \
--autoinstall-meta='kernel=w2k0.0 bootmgr=boot3ea.exe bcd=3Ea winpe=winpe.wim answerfile=wi2k3.sif post_install_script=post_install.cmd'

  • Although the ris-linux package is no longer supported, it also can still be used to install older Windows versions.

For example on Fedora 33:

dnf install chkconfig python27
dnf install ris-linux --releasever=24 --repo=updates,fedora
dnf install python3-dnf-plugin-versionlock
dnf versionlock add ris-linux
sed -i -r 's/(python)/\12/g' /sbin/ris-linuxd
sed -i -r 's/(\/winos\/inf)\//\1/g' /etc/sysconfig/ris-linuxd
sed -i -r 's/(\/usr\/share\/ris-linux\/infparser.py)/python2 \1/g' /etc/rc.d/init.d/ris-linuxd
sed -i 's/p = p + chr(252)/#&/g' /usr/share/ris-linux/binlsrv.py
mkdir -p /var/lib/tftpboot/winos/inf

To support 64 bit distributions:

cd /sbin
ln -s ris-linux ris-linux64
cd /etc/sysconfig
cp ris-linuxd ris-linuxd64
sed -i -r 's/(linuxd)/\164/g' ris-linuxd64
sed -i -r 's/(inf)/\164/g' ris-linuxd64
sed -i -r 's/(BINLSRV_OPTS=)/\1--port=4012/g' ris-linuxd64
cd /etc/rc.d/init.d
cp ris-linuxd ris-linuxd64
sed -i -r 's/(linuxd)/\164/g' ris-linuxd64
sed -i -e 's/RIS/RIS64/g' ris-linuxd64
systemctl daemon-reload
mkdir -p /var/lib/tftpboot/winos/inf64

copy the Windows network drivers to /var/lib/tftpboot/winos/inf[64] and start ris-linuxd[64]:

systemctl start ris-linuxd
systemctl start ris-linuxd64

6.3.5. Preparing boot files for RIS and legacy Windows XP and Windows 2003 Server

dnf install cabextract
cd /var/www/cobbler/distro_mirror/<distro_name>
mkdir boot
cp i386/ntdetect.com /var/lib/tftpboot
cabextract -dboot i386/setupldr.ex_

If you need to install Windows 2003 Server in addition to Windows XP, then to avoid a conflict, you can rename the ntdetect.com file:

mv /var/lib/tftpboot/ntdetect.com /var/lib/tftpboot/ntdetect.wxp
sed -i -e 's/ntdetect\.com/ntdetect\.wxp/g' boot/setupldr.exe

cp /var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/i386/ntdetect.com /var/lib/tftpboot/ntdetect.2k3
sed -i -e 's/ntdetect\.com/ntdetect\.2k3/g' /var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/boot/setupldr.exe
sed -bi "s/\x0F\xAB\x00\x00/\x0F\xAC\x00\x00/" /var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/boot/setupldr.exe

cabextract -dboot i386/startrom.n1_
mv Boot/startrom.n12 boot/pxeboot.n12
touch boot/boot.sdi

Copy the required drivers to the i386

cobbler distro add --name=WinXp_EN-i386 \
--kernel=/var/www/cobbler/distro_mirror/WinXp_EN-i386/boot/pxeboot.n12 \
--initrd=/var/www/cobbler/distro_mirror/WinXp_EN-i386/boot/boot.sdi \
--boot-files='@@local_img_path@@/i386/=@@web_img_path@@/i386/*.*' \
--arch=i386 --breed=windows –os-version=XP

cobbler distro add --name=Win2k3-Server_EN-x64 \
--kernel=/var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/boot/pxeboot.n12 \
--initrd=/var/www/cobbler/distro_mirror/Win2k3-Server_EN-x64/boot/boot.sdi \
--boot-files='@@local_img_path@@/i386/=@@web_img_path@@/[ia][3m][8d]6*/*.*' \
--arch=x86_64 --breed=windows --os-version=2003

cobbler profile add --name=WinXp_EN-i386 --distro=WinXp_EN-i386 --autoinstall=win.ks \
--autoinstall-meta='kernel=wine0.0 bootmgr=xple0 answerfile=wine0.sif'

cobbler profile add --name=Win2k3-Server_EN-x64 --distro=Win2k3-Server_EN-x64 --autoinstall=win.ks \
--autoinstall-meta='kernel=w2k0.0 bootmgr=w2k3l answerfile=wi2k3.sif'