CULT classic custom: usage
From Codtech
Download the latest CULT classic custom image from SourceForge mirrors.
Booting using a CDROM image
This represents a CULT classic custom live image. Can be tested with no risks in any computer or virtual machine. It will not use the local hard disk or any other local storage.
ISOLINUX boot loader
Normally, images have the ISOLINUX boot loader to avoid problems that were reported using rather old and buggy BIOS where GRUB fails to boot.
After booting from the CDROM this ISOLINUX menu is presented
Usage of the different client sessions are described in the following sections.
If Enter is pressed the system boots straight to the selected session or you can edit an ISOLINUX menu entry to modify the CULT: Kernel command line parameters used to boot.
GRUB boot loader
 | Note: GRUB is not in the default ISO image because some errors were reported when using old BIOSes |
After booting from the CDROM this GRUB menu is presented Image:CULT classic custom-cdrom boot.png
Usage of the different client sessions are described in the following sections.
If <Enter> is pressed the system boots straight to the selected session or you can edit a GRUB menu entry to modify the CULT: Kernel command line parameters used to boot.
Menu entries
CODTECH Universal Linux Thinclient 3.0 (rdp)
This is perhaps the most used entry.
The CDROM image is read-only and some values were decided at build time, so it's likely that you need to change them.
Among these values, the server name or IP address to be connected to through RDP is the most crucial.
This is explained in detail in CULT classic custom: Editing boot loader options and the available options in CULT:_Kernel_command_line_parameters#rdp.
In a nutshell you can configure RDP parameters. For example, to change the preconfigured Windows Terminal Server, that could be
... rdp=wts
this parameter can be edited to contain your Windows Terminal Server hostname or IP address
... rdp=192.168.100.1
Alternatively, adding wts.your.company.domain to your DNS avoids changing the command line.
Other parameters can also be passed to rdesktop the RDP client. These are exactly the same as parameters accepted by rdesktop with the only modification that command line withespaces must be replaced by +
... rdp=-a+16+-k+es+192.168.107.228:6789 ...
As mentioned above, any parameter accepted by rdesktop can be added here.
CODTECH Universal Linux Thinclient 3.0 (rdp verbose)
This adds verbose boot messages (as marked in the picture with the red dotted line). Boot parameters can be modified as explained in Editing a GRUB menu entry.
The IP address or hostname of the RDP server might have to be set.
These messages are a valuable tool to identify some problems during the boot process.
CODTECH Universal Linux Thinclient 3.0 (xdm)
The CDROM image is read-only and some values were decided at build time, so it's likely that you need to change them.
Among these values, the XDM connection method and possibly server name or IP address to be connected to through XDMCP.
This is explained in detail in CULT:_Kernel_command_line_parameters#xdm.
The image is pre-configured without an xdm parameter and this means that the default -broadcast is used (see initrd/scripts/startx).
In a nutshell you can configure XDM parameters as in
... xdm=-query+192.168.1.100 ...
CODTECH Universal Linux Thinclient 3.0 (xdm verbose)
This adds verbose boot messages (as marked in the image with the red dotted line). Boot parameters can be modified as explained in Editing a GRUB menu entry.
The XDM method and possibly the IP address or hostname of the XDM server might have to be set.
CODTECH Universal Linux Thinclient 3.0 (ask)
 | WARNING: This session is not yet fully implemented |
CODTECH Universal Linux Thinclient 3.0 (DEBUG)
This entry presents all off the boot messages with no splash.
Then, a terminal is launched.
CODTECH Universal Linux Thinclient 3.0 HELP
| WARNING: This session is not yet fully implemented |
Etherboot network boot
This starts a network boot process using Etherboot.
Local boot
Boot from the local device specified in BIOS.
Specifying IP address
If you are not using a DHCP server, or if by other reason you prefer to assign the IP address and other parameters manually, how to edit the boot loader and set the ip is explained in detail in CULT classic custom: Editing boot loader options and the available options in CULT:_Kernel_command_line_parameters#ip.
Using the VMware virtual thin client
A virtual thin client definition is provided to ease cult tests.
Download the virtual thin client definition from http://sourceforge.net/project/showfiles.php?group_id=207157&package_id=249907.
This can be used with VMware Workstation and VMware Player (free).
vmplayer
$ vmplayer "CULT (vmware 6).vmx"
Booting using a network bootable image
 | TIP: The content of the CDROM is compatible with the content of the TFTP server to provide network boot, so the only steps needed to achieve this are
|
The DHCP and TFTP server must be configured to boot the CULT classic custom kernel and image using the preferred boot loader.
The main advantage of this method agaist booting from the live CDROM is that you can permanently change CULT: Kernel command line parameters in the boot loader configuration file. This objective can also be reached by altering CDROM contents and generating the image again using the right tools.
Setting up TFTP server
TFTP is needed to serve the required files to boot diskless thin clients.
In most setups, the TFTP is chrooted to some directory for security reasons, a common place is /var/lib/tftpboot or /tftpboot. As the service runs inside this directory it must be stripped out from file's path.
In your filesystem, the real location for the configuration files will be inside /var/lib/tftpboot/cult directory.
Linux
Installation
Install TFTP server according to your distribution instructions. Usually the package is tftpd-hpa or tftp-server.
Ubuntu, Debian or derived distributions
For example, in Ubuntu or Debian
$ sudo apt-get install tftpd-hpa
RedHat, Fedora, RPM based
$ yum install tftp-server
Activate the service
Activate the TFTP server. Also be sure that no firewall is blocking the access to this service.
Configuration
This configuration uses /var/lib/tftpboot as the TFTP root and xinetd.
# default: off
# description: The tftp server serves files using the trivial file transfer \
# protocol. The tftp protocol is often used to boot diskless \
# workstations, download configuration files to network-aware printers, \
# and to start the installation process for some operating systems.
service tftp
{
disable = no
socket_type = dgram
protocol = udp
wait = yes
user = root
server = /usr/sbin/in.tftpd
server_args = -s /var/lib/tftpboot -v
per_source = 11
cps = 100 2
flags = IPv4
}
Microsoft Windows
In Microsft Windows there are different alternatives on selecting the TFTP and DHCP server. The simplest choice is to use tftpd32 available from its home page.
tftpd32 installation
Download from http://tftpd32.jounin.net/tftpd32_download.html and install tftpd32 as described in its documentation.
| WARNING: Latest tftpd32 versions have some problems. Our tests succeeded using tftpd32-3.03. Your mileage may vary. |
tftpd32 settings
 |
This screenshot shows the normal settings. In this case C:\var\lib\tftpboot is used as the TFTP root directory to keep consistency with other platforms. Also notice that DHCP has been disabled in this example which may or may not be your case. PXE Compatibility and Allow '\' as virtual root are other settings that should be checked. |
Verification and troubleshooting
To an earlier detection of any problem that may appear during the network boot process is advisable to verify the TFTP installation and functionality.
Using another computer, ideally on the same network that you intend to network boot clients, run a TFTP client to simulate the transfer that occurs during booting, and get the following list of files from the TFTP server.
- /cult/pxelinux.0
- /cult/vesamenu.c32
- /cult/pxelinux.cfg/codtech.png
- /cult/pxelinux.cfg/default
- /cult/vmlinuz
- /cult/cult.img
Setting up DHCP server
Linux
...
log(debug, substring(option vendor-class-identifier, 0, 9));
if substring (option vendor-class-identifier, 0, 9) = "PXEClient" {
filename "/cult/pxelinux.0";
}
...
Microsoft Windows
tftpd32 settings
In this case tftpd32 is used as the DHCP server. Microsoft Windows DHCP server can also be used.
The most important setting is the boot file name in this case /cult/pxelinux.0 which is the name of the boot loader.
cult folder
Copy the content of the CDROM into the TFTP root folder, in our examples this is /var/lib/tftpboot.
$ sudo cp -a /media/cdrom/cult /var/lib/tftpboot/
This includes all the necesary files to network boot cult clients.
| file or folder | description |
|---|---|
| isolinux | these are the needed files to boot the CDROM |
| pxelinux.cfg | this contains the files to use PXELINUX |
| cult.img | the cult ramdisk image |
| cult-3.0-classc-custom.initrd | symbolic link to cult.img |
| pxelinux.0 | PXELINUX boot loader |
| vesamenu.c32 | menu for ISOLINUX and PXELINUX |
| vmlinuz | the cult kernel |
| vmlinuz-2.6.20-15-generic | symbolic link to vmlinuz |
Boot loader
PXELINUX
PXELINUX can be used to boot the image and using vesamenu.c32 the needed entry should be something like this
label CODTECH Universal Linux Thinclient 3.0 (rdp verbose) MENU LABEL CODTECH Universal Linux Thinclient 3.0 (rdp verbose) kernel vmlinuz append boot=initrd vga=0x314 splash initrd=cult.img session=rdp rdp=wts
Use pxelinux.cfg/default from CDROM as the template for these files.
DEMO image
The CULT classic custom DEMO image timeouts the RDP session in 5 minutes, then this screen is presented indicating that this timeout has expired.
The session can be recovered at the same point that was left just pressing Enter or clicking the mouse.
XDM session has no timeout and can be used with this same DEMO image indefinitely.
To eliminate this timeout edit <INITRD>/conf/cult.conf and set
RDESKTOP_TIMEOUT=0
and rebuild the image.
Rebuilding the image
- In your Linux box mount the ISO usng a loop in any directry, for example /tmp/cdrom
- Extract the contents of /tmp/cdrom/cult/cult.img using gunzip and cpio
gunzip -c < /tmp/cdrom/cult/cult.img | cpio -ivdum
- Edit conf/cult.conf and set RDESKTOP_TIMEOUT=0
- Save
- Rebuild the initramfs
- Rebuild the ISO image
Errors
If there's any problem starting the session, connecting the session to the server or something else an error screen is presenting indicating the cause of the error so it can be fixed.
In this screen you can take several actions:
- pressing Esc , Enter or clicking the mouse will continue
- pressing H will halt the machine
- pressing R to reboot
