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(ii)Install these 6 packages ltsp-server-standalone dnsmasq epoptes epoptes-client ltsp-client resolvconf (and if you haven't already a desktop environment installed) a desktop environment of your choice. (ii)Install these 7 packages ltsp-server-standalone dnsmasq epoptes epoptes-client ltsp-client resolvconf rsync (and if you haven't already a desktop environment installed) a desktop environment of your choice.
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1. It may no longer be needed to add the server's user (example shows administrator) to the newly formed group epoptes but at the time of writing a bug has made it necessary. This command will do it: {{{ 1. Once epoptes is installed one must add the server's user (in the example "administrator") to the new epoptes group. This command will do it: {{{

Translation(s): Português Brasileiro


LTSP How To

Upstream documentation with official, detailed information about installing LTSP is at http://wiki.ltsp.org/wiki/LTSPedia.

Installating and configuring LTSP using the LTSP-PNP method

At the time of writing these versions of LTSP packages in Debian Stretch are:

server information: Distributor ID: Debian Description: Debian GNU/Linux 9.1 (stretch) Release: 9.1 Codename: stretch

server packages: ii ldm 2:2.2.18-2 ii ldm-server 2:2.2.18-2 ii ldm-themes 17.01 ii ltsp-client 5.5.9-2 ii ltsp-client-core 5.5.9-2 ii ltsp-docs 1.2-1 ii ltsp-server 5.5.9-2 ii ltsp-server-standalone 5.5.9-2 un ltsp-utils <none> ii ltspfs 1.4-2+b1 ii ltspfsd 1.4-2 ii ltspfsd-core 1.4-2+b1

This particular model has much less flexibilty since the clients must run the same version of distribution and platform as the server. The upside is that the model is easier to maintain. In the event that all clients can run the 64bit version this is recommended. Otherwise a 32bit version (Stretch i386 or Jessie i386) is suggested. There is no separate chroot (sometimes referred to as ltsp-pnp) and nbd (rather than nfs) is used to provide a squashfs image.

The use of dnsmasq provides ease of configurability and maintenance. The default config file generated provides its use as the tftp server as well as handling dhcp-proxy or dhcp-server proper with the adjustment of commenting and/or uncommenting lines provided. It can also be edited to run a local DNS cache on the server.

Also in this model no static addresses will be used. NetworkManager will be configured to use the router's dhcp server.

(i) Update the server, and check the files /etc/hostname and /etc/hosts are as desired.

(ii)Install these 7 packages ltsp-server-standalone dnsmasq epoptes epoptes-client ltsp-client resolvconf rsync (and if you haven't already a desktop environment installed) a desktop environment of your choice.

At the time of writing epoptes is at version 0.5.10-2.

All config files need to be edited using root privileges. Now start with configurations:

1. Once epoptes is installed one must add the server's user (in the example "administrator") to the new epoptes group. This command will do it:

sudo usermod -G epoptes -a administrator

Note that this new membership will only be activated in the next login.

2. We must edit NetworkManager's configuration in two places.

  • (a) Check in /etc/NetworkManager/NetworkManager.conf for the dns= key and comment out the line
    • #dns=dnsmasq
    (b) Launch nm-connection-editor from the command line. After launching: Choose the Wired connection and click Edit. Click on the IPv4 Settings tab. Choose 'Automatic (DHCP) addresses only' instead of just 'Automatic (DHCP)'. In the DNS servers field enter 127.0.0.1 first followed by one or two external DNS servers, separated by spaces (e.g. 127.0.0.1 208.67.222.222 8.8.8.8). Save these settings and close the window.

and then restart Network Manager with

sudo systemctl restart network-manager

3. Create a default configuration file for dnsmasq with the command

ltsp-config dnsmasq

Edit this file etc/dnsmasq.d/ltsp-server-dnsmasq.conf so that local dns caching is activated. Comment out

#port=0

When working with a server with one nic (only one subnet with the server, all clients and the router) check to see if the line

dhcp-range=x.y.z.0,proxy

corresponds to this subnet. If this is correct comment out the other range line

#dhcp-range=192.168.67.20,192.168.67.250,8h

If on the other hand the server has two nics be sure to connect the gigabit capable device to the switch with the clients and give that device the static ip 192.168.67.1 and leave both lines active (without the # symbol.)

Thus dnsmasq is the dhcp server for that subnet only.

Then restart dnsmasq with the command

sudo systemctl restart dnsmasq

4. Edit the config file /etc/ltsp/update-kernels.conf to have the uncommented lines

BOOT_METHODS=NBD
IPAPPEND=3

5. The version of the kernel running on the server can be determined with the command

uname -r

Note that at the time of writing the kernel was 4.9.0-3-686-pae in 32bit Stretch thus the command is

sudo dpkg-reconfigure linux-image-4.9.0-3-686-pae

This reports update-initramfs: Generating /boot/initrd.img-4.9.0-3-686-pae adding the changes above.

6. Inspect and edit as desired /etc/ltsp/ltsp-update-image.excludes as some software running on the server will not be appropriate for the clients.

7. Once the server has been updated and any additional software has been installed a new client filesystem image must be created in order for the clients to also have these updates. This is the command

sudo ltsp-update-image --cleanup /

This builds the latest squashfs image for nbd in /opt/ltsp/images and puts the latest kernel into /var/lib/tftpboot/ltsp/i386/.) It triggers "ltsp-config nbd-server" to create (if needed) the files /etc/nbd-server/conf.d/swap.conf and /etc/nbd-server/conf.d/ltsp_i386.conf. Check to see if both are there. It also creates /etc/nbd-client.

8. Then, create the default configuration file for the clients with the command

sudo ltsp-config lts.conf

9. Lastly reboot the server so that all changes are active including the user's membership in the group epoptes.

Notes

The lts.conf file should be studied and edited as appropriate. Note that all headings (written between square brackets) should have at least one entry each so don't leave any empty.

This file plays a role similar to xorg.conf for xorg and there are many options for it to choose from. One is worth mentioning here:

Under [Default] the option LDM_DIRECTX = True (the default is false) allows one to turn off the encrypted X tunnel via SSH, and instead run a less secure, but much faster unencrypted tunnel. If speed is important and security is less so then it is recommended.

In this model note that lts.conf is in/var/lib/tftpboot/ltsp/i386/ which among other things means that changes made to this file do NOT require a re-creation of the squashfs image.

When ready to try ltsp don't forget to create users as appropriate for the clients. This also does NOT require a re-creation of the squashfs image.

The following changes DO require a re-creation of the squashfs image:

When the server is updated.

Software is added to the server that is desirable for clients.

This means one repeats the step:

On the commandline run as root

ltsp-update-image --cleanup /

Installating and configuring LTSP using a separate chroot

This section documents a standard Debian LTSP installation on recent versions of Debian (wheezy and jessie), which uses NFS for a root filesystem, and ISC DHCPD.

  1. If you want a complete LTSP server with all the bells and

    whistles:

    apt-get install ltsp-server-standalone

    If you want more fine-grained control, splitting some services off to separate servers, you can install ltsp-server instead, and manually install each of the other services.

  2. Build the LTSP client environment, downloading packages from the internet:

    ltsp-build-client

    If your clients do not support 64-bit extensions (amd64), and your server is 64-bit, you may want to build your chroot specifying the i386 architecture:

    ltsp-build-client --arch i386
  3. Configure DHCP. Edit /etc/ltsp/dhcpd.conf to adapt to your network.

    Include the LTSP dhcpd.conf at the bottom of /etc/dhcp/dhcpd.conf:

    include "/etc/ltsp/dhcpd.conf";

    Restart isc-dhcp-server:

    service isc-dhcp-server restart
  4. Configure /etc/exports:

    /opt/ltsp *(ro,no_root_squash,async,no_subtree_check)

    Restart nfs-kernel-server:

    service nfs-kernel-server restart
  5. Boot a PXE capable machine and enjoy.

Installing LTSP with older versions

At the time of writing the version of LTSP in Debian Jessie is 5.5.2-1, while in Debian Wheezy 5.4.2-6+deb7u1. This particular model has much less flexibilty since the clients must run the same version of distribution and platform as the server. The upside is that the model is easier to maintain. Thus a 32bit version (Jessie i386 or Wheezy i386) is suggested. There is no separate chroot (sometimes referred to as ltsp-pnp) and nbd (rather than nfs) is used to provide a squashfs image.

The use of dnsmasq provides ease of configurability and maintenance. The default config file generated provides its use as the tftp server as well as handling dhcp-proxy or dhcp-server proper with the adjustment of commenting and/or uncommenting lines provided.

  1. Update the server, ensure the ip(s) is/are as desired (static is recommended) and /etc/hosts is as desired.
  2. Install ltsp-server-standalone, ltsp-client (since there is to be no separate chroot) dnsmasq (an easy to configure tool) other desired software and the desktop environment of your choice.
  3. On the commandline run as root

    ltsp-config dnsmasq
    This reports: Created /etc/dnsmasq.d/ltsp-server-dnsmasq.conf [ ok ] Restarting DNS forwarder and DHCP server: dnsmasq.
  4. If the server will run one subnet containing the Internet connection and the clients it need have only one network interface card. In this case dnsmasq can be configured to run a dhcp-proxy if there already is another dhcp server active. In this case edit the above file to comment out the dhcp range line and ensure there is a line (uncommented) stating dhcp-proxy.
  5. If the server will also run a dhcp-server then comment out the dhcp-proxy line and leave the dhcp-range line uncommented, ensuring the subnet entries are correct. Restart dnsmasq with

    service dnsmasq restart
  6. Edit the config file /etc/ltsp/update-kernels.conf to have the uncommented lines:

    BOOT_METHODS=NBD
    IPAPPEND=3
  7. The version of the kernel running on the server can be determined by:

    uname -r
  8. Note that at the time of writing the wheezy kernel was 3.2.0-4-486.

    dpkg-reconfigure linux-image-3.2.0-4-486
    This reports update-initramfs: Generating /boot/initrd.img-3.2.0-4-486 adding the changes above and triggers the call to /usr/share/ltsp/update-kernels.
  9. Inspect and edit as desired /etc/ltsp/ltsp-update-image.excludes as some software running on the server will not be appropriate for the clients.
  10. On the commandline run as root:

    ltsp-update-image --cleanup /
    This reports updating /var/lib/tftpboot directories for chroot: i386 (i.e. putting pxelinux.0 and pxelinux.cfg and the latest kernel into /var/lib/tftpboot/ltsp/i386/) and triggers ltsp-config nbd-server reporting created /etc/nbd-server/conf.d/swap.conf and created /etc/nbd-server/conf.d/ltsp_i386.conf and nbd-server. It also creates /etc/nbd-client but did not report it as well as putting the latest squashfs image for nbd into /opt/ltsp/images.
  11. On the commandline run as root:

    ltsp-config nbd-server
    This creates 3 files: /etc/nbd-server/conf.d/swap.conf /etc/nbd-client and /etc/nbd-server/conf.d/ltsp_i386.conf. If there is an error message "FATAL: Module overlayfs not found" it is a non-issue since aufs is used instead of overlayfs.
  12. On the commandline run as root:

    service nbd-server restart
  13. On the commandline run as root:

    ltsp-config lts.conf

At the time of writing Debian Jessie's version of xserver-xorg is 1.16. This may not run well on some older graphic cards. Debian Wheezy, on the other hand, has the 1.12 version and will work on many of those older graphic cards.