SettingUpLTSPserver < CF

CF Web>UbuntuLTSP>SettingUpLTSPserver (2024-11-26, MariHassanzada) (raw view)
---+ Setting Up an Ubuntu LTSP server (Obsolete)

---++ Introduction

This article describes how to set up an [[http://en.wikipedia.org/wiki/Linux_Terminal_Server_Project][LTSP server]] using fat clients and the i386 architecture. Options are included for thin clients and/or the amd64 architecture.

%TOC%

---++ Setting up an LTSP Server

1. Boot from Ubuntu 10.04 Alternate CD

2. Select LTSP Server from the Options menu (F4)

3. Select Install Ubuntu.

4. Make sure to set the Locale to Canadian so the server detects the CSC mirror as the closest.

5. When prompted, select =eth0= as the primary network interface.

6. The installer will attempt to auto-configure using DHCP, but it will fail. Select "configure network manually". The following settings are used in the LTSP test.

IP address: =129.97.170.228=

Netmask: =255.255.255.0=

Gateway: =129.97.170.1=

Name Server: =129.97.152.100 129.97.152.10=

Hostname: =ltsp1-gw-test=

Domain Name: =uwaterloo.ca=


7. Partition the hard drive according to the server configuration. The LTSP server needs about 30GB.

The installer will now install the base Ubuntu system.

8. Enter a username and password. The test server uses the 2010 CSCF-op account.

9. When asked to encrypt your home directory, select no.

Apt will try to download new packages and configurations from the internet or use those from the disk if it can't find them. After updating, the default image is built automatically (=amd64= thin client).


10. Indicated the interface that the thin clients are connected to. The test server uses eth1 for this purpose.

11. Install GRUB if necessary. If no bootloader exists already, just answer "yes" when the installer offers to install GRUB.

12. Answer "yes" to the configure the system to use UTC time.

13. The installation is completed. Unmount the CD drive or image that was loaded. The machine will restart automatically.

14. Open the terminal and execute the following command:

=sudo ltsp-build-client --arch i386 --fat-client=

This creates a 32-bit fat client image. This is a fairly lengthy process, but it does not require any user input along the way.

15. Open =/etc/network/interfaces= and configure the interface you chose to face the thin clients (=eth1= in this case). Change the network information from =192.168.0.*= to the appropriate values for your subnet (=10.15.49.*= in the test case).

16. Change the settings in =/etc/ltsp/dhcpd.conf= to be the same as above. The LTSP server should be in the option-routers field. In all the directories, change =amd64= to =i386= to set the 32-bit image as the default one. Make sure that the =option domain-name-servers= is set to the same DNS servers the host is using.

17. Restart the DHCP server with:

=sudo /etc/init.d/dhcp3-server restart=

Note that immediately after restarting the server, restarting the DHCP daemon or rebuilding the client image, the server may exhibit erratic behaviour for a few minutes. DHCP leases take a long time to get issued, valid logins will not register, clients freeze on startup, etc.

18. Now, it's time to add users. Users added to the server will be able to use the clients. Note that users that have the "do not ask for password on login" checkbox checked will still be required to enter a password when using a client. Additionally, =sudo= does not work when using the clients. All administrative changes to the image must be done from the server side. This step is not necessary if you set up [[https://www.cs.uwaterloo.ca/twiki/view/CF/ADAddUbuntu][Active Directory authentication]]. In this case, make sure the =/xhbin= directory contains symlinks to any user's default shell, or they will be unable to log in. Users that use =csh= or =tcsh= as their default shell experience problems establishing an X session on the server, so avoid those.
A basic server is now set up.

19. WARNING: If you used the guide linked to above to use Active Directory, edit the =/etc/nsswitch.conf= file to contain the following three lines instead of the ones given in the guide:

<verbatim>
passwd:    files ldap
group:       files
shadow:    files ldap
</verbatim>

If you do not, the client will attempt to enumerate all the groups. If you don't have a lot, you might not experience much slowdown, but it can take as much as several minutes to log in if you are in a large organization.



---++ Customizing your image

This section assumes you are working on an image named "i386". If you are editing a custom image, change =i386= to the name of your custom image.

1. Copy over the apt sources:

=sudo cp /etc/apt/sources.list /opt/ltsp/i386/etc/apt/sources.list=

2. Activate =chroot= and mount the filesystem:

=chroot /opt/ltsp/i386=

=mount -t proc proc /proc=

Note: while in =chroot=, you are root. When copying commands from the twiki, omit the "=sudo=" part. 

3. Update apt:

=apt-get update && apt-get dist-upgrade=

4. Use the command line to install whatever other packages you need.

5. When you're done, unmount the filesystem and exit.

=umount /proc=
=exit=

6. Before the clients can use your updates, you must update the image:

=ltsp-update-image --arch i386=

---++ Groups, Static IPs and Hostnames

It is possible to control various settings using the =/etc/ltsp/dhcp.conf= file. 

1. Open the =/etc/ltsp/dhcp.conf= file.
2. Within the subnet braces, insert the following lines:

<verbatim>
group

{
   use-host-decl-names on;
   host hostname
   {
      hardware ethernet macaddress;
      fixed-address ipaddress;
   }
}
</verbatim>

3. Replace =hostname= with the client's name, =macaddress= with the client's MAC address and =ipaddress= with the desired static IP address. 

4. Add additional hosts or groups if necessary. 

5. You must restart the DHCP server for changes to take effect:

=sudo /etc/init.d/dhcp3-server restart=

---++ Multiple Images

It is also possible to have clients in a group boot from a different image than the default one.

1. Build a base for your custom image:

=sudo ltsp-build-client --arch i386 --fat-client --chroot i386-custom=

This will create an image that is identical in every way to the default =i386= image, except with a different name. You may also omit the =fat-client= option to built a thin client image and omit the =--arch= option to build a 64 bit image. The =--chroot= option changes the name of the image. =i386-custom= can be replaced with whatever name you want.

2. Update and customize the image using the steps described in the "Customizing your image" section.

3. Edit the =/etc/ltsp/dhcpd.conf= file as described in the "Groups, Static IPs and Hostnames" section. Create at least one group that will use the custom image.

4. Add the following lines in that group:

<verbatim>
if substring( option vendor-class-identifier , 0 , 9 ) = "PXEClient"
{
   filename "/ltsp/i386-custom/pxelinux.0";
}
else
{
   filename "/ltsp/i386-custom/nbi.img";
}
option root-path "/opt/ltsp/i386-custom/";
</verbatim>

5. Restart the DHCP server:

=sudo /etc/init.d/dhcp3-server restart=

The clients in that group will now boot using the specialized image.

---++Customizing the login screen

By default, the login screen is a splash of orange and the Ubuntu logo. This can be modified by replacing images in the =opt/ltsp/i386/usr/share/ldm/themes/ubuntu/= directory, namely the background, =bg.png= and the logo, =logo.png=. Various color settings can be found in =greeter-gtkrc=. 



-- Main.PhilipBeldowski - 24 Sep 2010
-- Main.PeterSamsonov - 05 Oct 2010
Topic revision: r11 - 2024-11-26 - MariHassanzada
Information in this area is meant for use by CSCF staff and is not official documentation, but anybody who is interested is welcome to use it if they find it useful.
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