Debian Edu / Skolelinux is a Linux distribution created by the Debian Edu project. As a Debian Pure Blend distribution it is an official Debian subproject.

What this means for your school is that Skolelinux is a version of Debian providing an out-of-the box environment of a completely configured school-network.

The Skolelinux project in Norway was founded on July 2nd 2001 and about the same time Raphaël Hertzog started Debian-Edu in France. Since 2003 both projects are united, but both names stayed. "Skole" and (Debian-)"Education" are just two well understood terms in these regions.

Today the system is in use in several countries around the world.

This section of the document describes the network architecture and services provided by a Skolelinux installation.

The figure is a sketch of the assumed network topology. The default setup of a Skolelinux network assumes that there is one (and only one) main server, while allowing the inclusion of both normal workstations and LTSP servers (with associated thin clients and/or diskless workstations). The number of workstations can be as large or small as you want (starting from none to a lot). The same goes for the LTSP servers, each of which is on a separate network so that the traffic between the clients and the LTSP server doesn't affect the rest of the network services. LTSP is explained in detail in the related HowTo chapter.

The reason that there can only be one main server in each school network is that the main server provides DHCP, and there can be only one machine doing so in each network. It is possible to move services from the main server to other machines by setting up the service on another machine, and subsequently updating the DNS configuration, pointing the DNS alias for that service to the right computer.

In order to simplify the standard setup of Skolelinux, the Internet connection runs over a separate router, also called gateway. See the Internet router chapter for details how to set up such a gateway if it is not possible to configure an existing one as needed.

All the Linux machines that are installed with the Skolelinux installer will be administrable from a central computer, most likely the server. It will be possible to log in to all machines via SSH, and thereby have full access to the machines. As root one needs to run kinit first to get a Kerberos TGT.

All user information is kept in an LDAP directory. Updates of user accounts are made against this database, which is used by the clients for user authentication.

The purpose of the different profiles is explained in the network architecture chapter.

If LTSP is intended to be used, take a look at the LTSP Hardware Requirements wiki page.

A list of tested hardware is provided at https://wiki.debian.org/DebianEdu/Hardware/ . This list is not nearly complete.

https://wiki.debian.org/InstallingDebianOn is an effort to document how to install, configure and use Debian on some specific hardware, allowing potential buyers to know if that hardware is supported and existing owners to know how get the best out of that hardware.

When using the default network architecture, these rules apply:

A router/gateway, connected to the Internet on the external interface and running on the IP address 10.0.0.1 with netmask 255.0.0.0 on the internal interface, is needed to connect to the Internet.

The router should not run a DHCP server, it can run a DNS server, though this is not needed and will not be used.

In case you do not already have a router or your existing router cannot be set up accordingly, any machine which fulfills the requirements for a minimal Debian installation and which has at least two network interfaces can be turned into a gateway between the existing network and the Debian Edu one. See installation documentation for a simple way to install and set up a Debian machine using debian-edu-router-config.

If you need something for an embedded router or accesspoint we recommend using OpenWRT, though of course you can also use the original firmware. Using the original firmware is easier; using OpenWRT gives you more choices and control. Check the OpenWRT webpages for a list of supported hardware.

It is possible to use a different network setup (there is a documented procedure to do this), but if you are not forced to do this by an existing network infrastructure, we recommend against doing so and recommend you stay with the default network architecture.

We recommend that you read or at least take a look at the release notes for Debian Bookworm before you start installing a system for production use. There is more information about the Debian Bookworm release available in its installation manual.

Please give Debian Edu/Skolelinux a try, it should just work.

It is recommended, though, to read the chapters about hardware and network requirements and about the architecture before starting to install a main server.

Be sure to also read the getting started chapter of this manual, as it explains how to log in for the first time.

When you do a Debian Edu installation, you have a few options to choose from. Don't be afraid; there aren't many. We have done a good job of hiding the complexity of Debian during the installation and beyond. However, Debian Edu is Debian, and if you want there are more than 59,000 packages to choose from and a billion configuration options. For the majority of our users, our defaults should be fine. Please note: if LTSP is intended to be used, choose a lightweight desktop environment.

DEBIAN_FRONTEND=noninteractive apt install -y -q debian-edu-router-config

lshw -class network

ip addr flush <interface>

dpkg-reconfigure --force uif debian-edu-router

deb http://deb.debian.org/debian/ bookworm main 
deb http://security.debian.org bookworm-security main 

sudo dd if=debian-edu-amd64-XXX.iso of=/dev/sdX bs=1M

lsblk -p

/usr/share/debian-edu-config/tools/pxe-addfirmware

d-i    pkgsel/include string my-extra-package(s)

The text mode and the graphical installation are functionally identical - only the appearance is different. The graphical mode offers the opportunity to use a mouse, and of course looks much nicer and more modern. Unless the hardware has trouble with the graphical mode, there is no reason not to use it.

So here is a screenshot tour through a graphical 64-bit Main Server + Workstation + LTSP Server installation (in BIOS mode) and how it looks at the first boot of the main server and a PXE boot on the LTSP client network (thin client session screen - and login screen after the session on the right has been clicked).

During installation of the main server a first user account was created. In the following text this account will be referenced as "first user". This account is special, as the home directory permission is set to 700 (so chmod o+x ~ is needed to make personal web pages accessible), and the first user can use sudo to become root.

See the information about Debian Edu specific file system access configuration before adding users; adjust to your site's policy if needed.

After the installation, the first things you need to do as first user are:

Adding users and workstations is described in detail below, so please read this chapter completely. It covers how to perform these minimum steps correctly as well as other stuff that everybody will probably need to do.

There is additional information available elsewhere in this manual: the New features in Bookworm chapter should be read by everyone who is familiar with previous releases. And for those upgrading from a previous release, make sure to read the Upgrades chapter.

If generic DNS traffic is blocked out of your network and you need to use some specific DNS server to look up internet hosts, you need to tell the DNS server to use this server as its "forwarder". Update /etc/bind/named.conf.options and specify the IP address of the DNS server to use.

The HowTo chapter covers more tips and tricks and some frequently asked questions.

GOsa² is a web based management tool that helps to manage some important parts of your Debian Edu setup. With GOsa² you can manage (add, modify, or delete) these main groups:

For GOsa² access you need the Skolelinux main server and a (client) system with a web browser installed which can be the main server itself if it was installed as a so called combined server (Main Server + LTSP Server + Workstation profiles).

If you (probably accidentally) installed a pure Main Server profile and don't have a client with a web-browser handy, it's easy to install a minimal desktop on the main server using this command sequence in a (non-graphical) shell as the user you created during the main server's installation (first user):

  $ sudo apt update
  $ sudo apt install task-desktop-xfce lightdm education-menus
  $ sudo service lightdm start

From a web browser use the URL https://www/gosa for GOsa² access, and log in as the first user.

First, click on "Users" in the left navigation menu. The right side of the screen will change to show a table with department folders for "Students" and "Teachers" and the account of the GOsa² Administrator (the first created user). Above this table you can see a field called Base that allows you to navigate through your tree structure (move your mouse over that area and a drop-down menu will appear) and to select a base folder for your intended operations (e.g. adding a new user).

The management of groups is very similar to the management of users.

You can enter a name and a description per group. Make sure that you choose the right level in the LDAP tree when creating a new group.

Adding users to a newly created group takes you back to the user list, where you most probably would like to use the filter box to find users. Check the LDAP tree level, too.

The groups entered in the group management are also regular unix groups, so you can use them for file permissions too.

Machine management basically allows you to manage all networked devices in your Debian Edu network. Every machine added to the LDAP directory using GOsa² has a hostname, an IP address, a MAC address and a domain name (which is usually "intern"). For a fuller description of the Debian Edu architecture see the architecture chapter of this manual.

Diskless workstations and thin clients work out-of-the-box in case of a combined main server.

Workstations with disks (including separate LTSP servers) have to be added with GOsa². Behind the scenes, both a machine specific Kerberos Principal (sort of account) and a related keytab file (containing a key used as password) are generated; the keytab file needs to be present on the workstation to be able to mount users' home directories. Once the added system has been rebooted, log into it as root and run /usr/share/debian-edu-config/tools/copy-host-keytab.

To create Principal and keytab file for a system already configured with GOsa², log in on the main server as root and run

/usr/share/debian-edu-config/tools/gosa-modify-host <hostname> <IP>

Please note: host keytab creation is possible for systems of type workstations, servers and terminals but not for those of type netdevices. See the Network clients HowTo chapter for NFS configuration options.

To add a machine, use the GOsa² main menu, systems, add. The name of the machine is expected to be a valid unqualified hostname, do not add the domain name here. You can use an IP address/hostname from the preconfigured address space 10.0.0.0/8. Currently there are only two predefined fixed addresses: 10.0.2.2 (tjener) and 10.0.0.1 (gateway). The addresses from 10.0.16.20 to 10.0.31.254 (roughly 10.0.16.0/20 or 4000 hosts) are reserved for DHCP and are assigned dynamically.

To assign a host with the MAC address 52:54:00:12:34:10 a static IP address in GOsa² you have to enter the MAC address, the hostname and the IP; alternatively you might click the Propose ip button which will show the first free fixed address in 10.0.0.0/8, most probably something like 10.0.0.2 if you add the first machine this way. It may be better to first think about your network: for example you could use 10.0.0.x with x>10 and x<50 for servers, and x>100 for workstations. Don't forget to activate the just added system. With the exception of the main server all systems will then have a matching icon.

If the machines have booted as thin clients/diskless workstations or have been installed using any of the networked profiles, the sitesummary2ldapdhcp script can be used to automatically add machines to GOsa². For simple machines it will work out of the box, for machines with more than one mac address the actually used one has to be chosen, sitesummary2ldapdhcp -h shows usage information. Please note, that the IP addresses shown after usage of sitesummary2ldapdhcp belong to the dynamic IP range. These systems can then be modified to suit your network: rename each new system, activate DHCP and DNS, add it to netgroups (see screenshot below for recommended netgroups), reboot the system afterwards. The following screenshots show how this looks in practice:

root@tjener:~# sitesummary2ldapdhcp -a -i ether-22:11:33:44:55:ff
info: Create GOsa machine for am-2211334455ff.intern [10.0.16.21] id ether-22:11:33:44:55:ff.
 
Enter password if you want to activate these changes, and ^c to abort.
 
Connecting to LDAP as cn=admin,ou=ldap-access,dc=skole,dc=skolelinux,dc=no
enter password: ********
root@tjener:~#

A cronjob updating DNS runs every hour; su -c ldap2bind can be used to trigger the update manually.

The package p910nd is installed by default on a system with the Workstation profile.

It is recommended to disable all self-advertising features in the used network printers. Instead, assign a fixed IP address with GOsa² and configure them as AppSocket/HP JetDirect network printers.

This section explains how to use apt full-upgrade.

Using apt is really simply. To update a system you need to execute two commands on the command line as root: apt update (which updates the lists of available packages) and apt full-upgrade (which upgrades the packages for which an upgrade is available).

It is also a good idea to upgrade using the C locale to get English output which in cases of problems is more likely to produce results in search engines.

LC_ALL=C apt full-upgrade -y

After upgrading the debian-edu-config package, changed Cfengine configuration files might be available. Run ls -ltr /etc/cfengine3/debian-edu/ to check if this is the case. To apply the changes, run LC_ALL=C cf-agent -D installation.

It is important to run debian-edu-ltsp-install --diskless_workstation yes after LTSP server upgrades to keep the SquashFS image for diskless clients in sync.

After a point release upgrade of a system with Main Server or LTSP Server profile, debian-edu-pxeinstall needs to be run to update the PXE installation environment.

It is also a good idea to install cron-apt and apt-listchanges and configure them to send mail to an address you are reading.

cron-apt will notify you once a day via email about any packages that can be upgraded. It does not install these upgrades, but does download them (usually in the night), so you don't have to wait for the download when you do apt full-upgrade.

Automatic installation of updates can be done easily if desired, it just needs the unattended-upgrades package to be installed and configured as described on wiki.debian.org/UnattendedUpgrades.

apt-listchanges can send new changelog entries to you via email, or alternatively display them in the terminal when running apt.

For backup management point your browser to https://www/slbackup-php. Please note that you need to access this site via SSL, since you have to enter the root password there. If you try to access this site without using SSL it will fail.

Note: the site will only work if you temporarily allow SSH root login on the backup server, which is the main server (tjener.intern) by default.

By default, backups of /skole/tjener/home0, /etc/, /root/.svk and LDAP are stored in the /skole/backup/ directory which is managed as separate partition by LVM. If you only want to have spare copies of things (in case you delete them) this setup should be fine for you.

Be aware that this backup scheme doesn't protect you from failing hard drives.

If you want to back up your data to an external server, a tape device or another hard drive you'll have to modify the existing configuration a bit.

If you want to restore a complete folder, your best option is to use the command-line:

$ sudo rdiff-backup -r <date>  \
   /skole/backup/tjener/skole/tjener/home0/user \
   /skole/tjener/home0/user_<date>

This will leave the content from /skole/tjener/home0/user for <date> in the folder /skole/tjener/home0/user_<date>

If you want to restore a single file, then you should be able to select the file (and the version) from the web interface, and download only that file.

If you want to get rid of older backups, choose "Maintenance" in the menu on the backup page and select the oldest snapshot to keep:

More information about Debian Edu customisations useful for system administrators can be found in the Administration Howto chapter and in the Advanced administration Howto chapter

Upgrading Debian from one distribution to the next is generally rather easy. For Debian Edu this is unfortunately a bit more complicated as we modify configuration files in ways we shouldn't. However we have documented the needed steps below. (See Debian bug 311188 for more information how Debian Edu should modify configuration files.)

In general, upgrading the servers is more difficult than the workstations and the main server is the most difficult to upgrade.

If you want to be sure that after the upgrade everything works as before, you should test the upgrade on a test system or systems configured the same way as your production machines. There you can test the upgrade without risk and see if everything works as it should.

Make sure to also read the information about the current Debian Stable release in its installation manual.

It may also be wise to wait a bit and keep running Oldstable for a few weeks longer, so that others can test the upgrade and document any problems they experience. The Oldstable release of Debian Edu will receive continued support for some time after the next Stable release, but when Debian ceases support for Oldstable, Debian Edu will necessarily do the same.

Be prepared: make sure you have tested the upgrade from Bullseye in a test environment or have backups ready to be able to go back.

Please note that the following recipe applies to a default Debian Edu main server installation (desktop=xfce, profiles Main Server, Workstation, LTSP Server). (For a general overview concerning Bullseye to Bookworm upgrade, see: https://www.debian.org/releases/bookworm/releasenotes)

Don't use X, use a virtual console, log in as root.

If apt finishes with an error, try to fix it and/or run apt -f install and then apt -y full-upgrade once again.

apt update
apt full-upgrade

sed -i 's/bullseye/bookworm/g' /etc/apt/sources.list
export LC_ALL=C
apt update
apt upgrade --without-new-pkgs
apt full-upgrade

cf-agent -v -D installation

To upgrade from any older release, you will need to upgrade to the Bullseye based Debian Edu release first, before you can follow the instructions provided above. Instructions are given in the Manual for Debian Edu Bullseye about how to upgrade to Bullseye from the previous release, Buster.

Using etckeeper, all files in /etc/ are tracked using Git as a version control system.

This makes it possible to see when a file is added, changed and removed, as well as what was changed if the file is a text file. The git repository is stored in /etc/.git/.

Every hour, any changes are automatically recorded, allowing configuration history to be extracted and reviewed.

To look at the history, the command etckeeper vcs log is used. To check the differences between two points in time, a command like etckeeper vcs diff can be used.

See the output of man etckeeper for more information.

List of useful commands:

etckeeper vcs log
etckeeper vcs status
etckeeper vcs diff
etckeeper vcs add .
etckeeper vcs commit -a
man etckeeper

etckeeper vcs log

etckeeper vcs status

etckeeper vcs commit -a /etc/resolv.conf

In Debian Edu, all partitions other than the /boot/ partition are on logical LVM volumes. With Linux kernels since version 2.6.10, it is possible to extend partitions while they are mounted. Shrinking partitions still needs to happen while the partition is unmounted.

It is a good idea to avoid creating very large partitions (over, say, 20GiB), because of the time it takes to run fsck on them or to restore them from backup if the need arises. It is better, if possible, to create several smaller partitions than one very large one.

The helper script debian-edu-fsautoresize is provided to make it easier to extend full partitions. When invoked, it reads the configuration from /usr/share/debian-edu-config/fsautoresizetab, /site/etc/fsautoresizetab and /etc/fsautoresizetab. It then proposes to extend partitions with too little free space, according to the rules provided in these files. If run with no arguments, it will only show the commands needed to extend the file system. The argument -n is needed to actually execute these commands to extend the file systems.

The script is executed automatically every hour on every client listed in the fsautoresize-hosts netgroup.

When the partition used by the Squid proxy is resized, the value for cache size in etc/squid/squid.conf needs to be updated as well. The helper script /usr/share/debian-edu-config/tools/squid-update-cachedir is provided to do this automatically, checking the current partition size of /var/spool/squid/ and configuring Squid to use 80% of this as its cache size.

lvextend -L30G /dev/vg_system/skole+tjener+home0
resize2fs /dev/vg_system/skole+tjener+home0

ldapvi is a tool to edit the LDAP database with a normal text editor on the commandline.

The following needs to be executed:

ldapvi -ZD '(cn=admin)'

Note: ldapvi will use whatever is the default editor. By executing export EDITOR=vim in the shell prompt one can configure the environment to get a vi clone as editor.

Warning: ldapvi is a very powerful tool. Be careful and don't mess up the LDAP database, same warning applies for JXplorer.

Using Kerberos for NFS to mount home directories is a security feature. Workstations and LTSP clients won't work without Kerberos. The levels krb5, krb5i and krb5p are supported (krb5 means Kerberos authentication, i stands for integrity check and p for privacy, i.e. encryption); the load on both server and workstation increases with the security level, krb5i is a good choice and has been chosen as default.

/srv/nfs4        gss/krb5i(rw,sync,fsid=0,crossmnt,no_subtree_check)
/srv/nfs4/home0  gss/krb5i(rw,sync,no_subtree_check)

This tool allows to set the default printer depending on location, machine, or group membership. For more information, see /usr/share/doc/standardskriver/README.md.

The configuration file /etc/standardskriver.cfg has to be provided by the admin, see /usr/share/doc/standardskriver/examples/standardskriver.cfg as an example.

If you prefer a GUI to work with the LDAP database, check out the jxplorer package, which is installed by default. To get write access connect like this:

host: ldap.intern
port: 636
Security level: ssl + user + password
User dn: cn=admin,ou=ldap-access,dc=skole,dc=skolelinux,dc=no

ldap-createuser-krb is a small command line tool to create user accounts, it is invoked as follows:

ldap-createuser-krb5 [-u uid] [-g gid] [-G group[,group]...] [-d department] <username> <gecos>

All arguments except the username and GECOS field are optional, the latter usually should contain the full name of the user. Unless specified the tool will pick the next free UID and GID automatically and not assign any additional groups to the user. If no department is given, it will pick the first gosaDepartment from LDAP which is likely skole and for regular users usually not what you want, so you should pick an appropriate value for the user, e.g. Teachers or Students. After entering and confirming the password and entering the LDAP administrator password, ldap-createuser-krb5 will create the user account in LDAP, set the Kerberos password, create the home directory, and add a corresponding Samba user. The following screenshot shows an example invocation to create a user account named harhir for a teacher whose full name is "Harry Hirsch":

root@tjener:~# ldap-createuser-krb5 -d Teachers harhir "Harry Hirsch"
new user password: 
confirm password: 

dn: uid=harhir,ou=people,ou=Teachers,dc=skole,dc=skolelinux,dc=no
changetype: add
objectClass: top
objectClass: person
objectClass: organizationalPerson
objectClass: inetOrgPerson
objectClass: gosaAccount
objectClass: posixAccount
objectClass: shadowAccount
objectClass: krbPrincipalAux
objectClass: krbTicketPolicyAux
sn: Harry Hirsch
givenName: Harry Hirsch
uid: harhir
cn: Harry Hirsch
userPassword: {CRYPT}$y$j9T$TWnq55O1rvyLhjF.$oVf.t.RXC1v/4Y8FhV0umno629mo7bP7/YJyig6HET6
homeDirectory: /skole/tjener/home0/harhir
loginShell: /bin/bash
uidNumber: 1004
gidNumber: 1004
gecos: Harry Hirsch
shadowLastChange: 19641
shadowMin: 0
shadowMax: 99999
shadowWarning: 7
krbPwdPolicyReference: cn=users,cn=INTERN,cn=kerberos,dc=skole,dc=skolelinux,dc=no
krbPrincipalName: harhir@INTERN

ldap_initialize( <DEFAULT> )
Enter LDAP Password: 
add objectClass:
        top
        person
        organizationalPerson
        inetOrgPerson
        gosaAccount
        posixAccount
        shadowAccount
        krbPrincipalAux
        krbTicketPolicyAux
add sn:
        Harry Hirsch
add givenName:
        Harry Hirsch
add uid:
        harhir
add cn:
        Harry Hirsch
add userPassword:
        {CRYPT}$y$j9T$TWnq55O1rvyLhjF.$oVf.t.RXC1v/4Y8FhV0umno629mo7bP7/YJyig6HET6
add homeDirectory:
        /skole/tjener/home0/harhir
add loginShell:
        /bin/bash
add uidNumber:
        1004
add gidNumber:
        1004
add gecos:
        Harry Hirsch
add shadowLastChange:
        19641
add shadowMin:
        0
add shadowMax:
        99999
add shadowWarning:
        7
add krbPwdPolicyReference:
        cn=users,cn=INTERN,cn=kerberos,dc=skole,dc=skolelinux,dc=no
add krbPrincipalName:
        harhir@INTERN
adding new entry "uid=harhir,ou=people,ou=Teachers,dc=skole,dc=skolelinux,dc=no"
modify complete

Authenticating as principal root/admin@INTERN with password.
kadmin.local:  change_password harhir@INTERN
Enter password for principal "harhir@INTERN": 
Re-enter password for principal "harhir@INTERN": 
Password for "harhir@INTERN" changed.
kadmin.local:  lpcfg_do_global_parameter: WARNING: The "encrypt passwords" option is deprecated
Added user harhir.

While you can use stable-updates directly, you don't have to: stable-updates are pushed into the stable suite regularly when stable point releases are done, which roughly happens every two months.

You are running Debian Edu because you prefer the stability of Debian Edu. It runs great; there is just one problem: sometimes software is a little bit more outdated than you like. This is where backports.debian.org steps in.

Backports are recompiled packages from Debian testing (mostly) and Debian unstable (in a few cases only, e.g. security updates), so they will run without new libraries (wherever this is possible) on a stable Debian distribution like Debian Edu. We recommend you to pick out individual backports which fit your needs, and not to use all backports available there.

Using backports is simple:

echo "deb http://deb.debian.org/debian/ bookworm-backports main" > /etc/apt/sources.list.d/bookworm-backports.sources.list
apt update

After which one can install backported packages easily, the following command will install a backported version of tuxtype:

apt install tuxtype/bookworm-backports

Backports are automatically updated (if available) just like other packages. Like the normal archive, backports has three sections: main, contrib and non-free.

If you want to upgrade from one version to another (for example from Bookworm 12.1 to 12.2) but you do not have Internet connectivity, only physical media, follow these steps:

Insert the CD / DVD / Blu-ray disc / USB flash drive and use the apt-cdrom command:

apt-cdrom add

To quote the apt-cdrom(8) man page:

Then run these two commands to upgrade the system:

apt update
apt full-upgrade

killer is a perl script that gets rid of background jobs. Background jobs are defined as processes that belong to users who are not currently logged into the machine. It's run by cron job once an hour.

unattended-upgrades is a Debian package which will install security (and other) upgrades automatically. If installed, the package is preconfigured to install security upgrades. The logs are available in /var/log/unattended-upgrades/; also, there are always /var/log/dpkg.log and /var/log/apt/.

It is possible to save energy and money by automatically turning client machines off at night and back on in the morning. The package shutdown-at-night will try to turn off the machine every hour on the hour from 16:00 in the afternoon, but will not turn it off if it seems to have users. It will try to tell the BIOS to turn on the machine around 07:00 in the morning, and the main server will try to turn on machines from 06:30 by sending Wake-on-LAN packets. These times can be changed in the crontabs of individual machines.

Some considerations should be kept in mind when setting this up:

  #!/bin/sh
  PATH=/usr/sbin:$PATH
  export PATH
  sitesummary-nodes -w

  #!/bin/sh
  PATH=/usr/sbin:$PATH
  export PATH
  netgroup -h shutdown-at-night-hosts

To access machines behind a firewall from the Internet, consider installing the package autossh. It can be used to set up an SSH tunnel to a machine on the Internet that you have access to. From that machine, you can access the server behind the firewall via the SSH tunnel.

In the default installation, all services are running on the main server, hostname tjener. To simplify moving some to another machine, there is a minimal installation profile available. Installing with this profile will lead to a machine, which is part of the Debian Edu network, but which doesn't have any services running (yet).

These are the required steps to setup a machine dedicated to some services:

FIXME: The HowTos from https://wiki.debian.org/DebianEdu/HowTo/ are either user- or developer-specific. Let's move the user-specific HowTos over here (and delete them over there)! (But first ask the authors (see the history of those pages to find them) if they are fine with moving the howto and putting it under the GPL.)

Take these steps to set up a dedicated storage server for user home directories and possibly other data.

Now users should be able to access the files on 'nas-server.intern' directly by just visiting the '/tjener/nas-server/storage/' directory using any application on any workstation, LTSP thin client or LTSP server.

There are several ways to restrict SSH login, some are listed here.

+ : alice jane bob john : ALL
+ : ALL : 10.0.0.0/8 192.168.0.0/24 192.168.1.0/24
- : ALL : ALL
#

To support multiple languages these steps need to be done:

Users will then be able to choose the language via the LightDM display manager before logging in; this applies to Xfce, LXDE and LXQt. GNOME and KDE both come with their own internal region and language configuration tools, use these. MATE uses the Arctica greeter on top of LightDM whithout a language chooser. Run apt purge arctica-greeter to get the stock LightDM greeter.

libdvdcss is needed for playing most commercial DVDs. For legal reasons it's not included in Debian (Edu). If you are legally allowed to use it, you can build your own local packages using the libdvd-pkg Debian package; make sure contrib is enabled in /etc/apt/sources.list.

apt update
apt install libdvd-pkg

Answer the debconf questions, then run dpkg-reconfigure libdvd-pkg.

The package fonts-linex (which is installed by default) installs the font "Abecedario" which is a nice handwriting font for kids. The font has several forms to be used with kids: dotted, and with lines.

One generic term for both thin clients and diskless workstations is LTSP client.

Starting with Bullseye, LTSP is quite different from the previous versions. This concerns both setup and maintenance.

For information about LTSP in general, see the LTSP homepage. On systems with LTSP server profile, man ltsp provides more information.

Please note that the ltsp tool from LTSP has to be used carefully. For example, ltsp image / would fail to generate the SquashFS image in case of Debian machines (these have a separate /boot partition by default), ltsp ipxe would fail to generate the iPXE menu correctly (due to Debian Edu's thin client support), and ltsp initrd would mess up LTSP client boot completely.

The debian-edu-ltsp-install tool is a wrapper script for ltsp image, ltsp initrd and ltsp ipxe. It is used to setup and configure diskless workstation and thin client support (both 64-Bit and 32-Bit PC). See man debian-edu-ltsp-install or the script content to see how it works. All configuration is contained in the script itself (HERE documents) to facilitate site specific adjustments.

Examples how to use the wrapper script debian-edu-ltsp-install:

Besides bare (smallest thin client system), also display and desktop are available options. The display type offers a shutdown button, the desktop type runs Firefox ESR in kiosk mode on the client itself (more local RAM and CPU power required, but server load reduced).

The debian-edu-ltsp-ipxe tool is a wrapper script for ltsp ipxe. It makes sure that the /srv/tftp/ltsp/ltsp.ipxe file is Debian Edu specific. The command needs to be run after iPXE menu related items (like menu timeout or default boot settings) in the /etc/ltsp/ltsp.conf [server] section have been modified.

The debian-edu-ltsp-initrd tool is a wrapper script for ltsp initrd. It makes sure that a use case specific initrd (/srv/tftp/ltsp/ltsp.img) is generated and then moved to the use case related directory. The command needs to be run after the /etc/ltsp/ltsp.conf [clients] section has been modified.

The debian-edu-ltsp-chroot tool is a replacement for the ltsp-chroot tool shipped with LTSP5. It is used to execute commands in a specified LTSP chroot (like e.g. install, upgrade and remove packages).

Diskless workstation

A diskless workstation runs all software locally. The client machines boot directly from the LTSP server without a local hard drive. Software is administered and maintained on the LTSP server, but runs on the diskless workstations. Home directories and system settings are stored on the server too. Diskless workstations are an excellent way of reusing older (but powerful) hardware with the same low maintenance costs as with thin clients.

Unlike workstations diskless workstations run without any need to add them with GOsa².

Thin client

A thin client setup enables an ordinary PC to function as an (X-)terminal, where all software runs on the LTSP server. This means that this machine boots via PXE without using a local client hard drive and that the LTSP server needs to be a powerful machine.

Debian Edu still supports the use of thin clients to enable the use of very old hardware.

Since Thin clients use X2Go, users should disable compositing to avoid display artefacts. In the default case (Xfce desktop environment): Settings -> Window Manager Tweaks -> Compositor.

LTSP client firmware

LTSP client boot will fail if the client's network interface requires a non-free firmware. A PXE installation can be used for troubleshooting problems with netbooting a machine; if the Debian Installer complains about a missing XXX.bin file then non-free firmware has to be added to the LTSP server's initrd.

Proceed like this on the LTSP server:

apt update && apt search ^firmware-

apt -y -q install firmware-linux

debian-edu-ltsp-install --diskless_workstation yes

/usr/share/debian-edu-config/tools/ltsp-addfirmware -h

ltsp image x2go-bare-amd64

debian-edu-ltsp-install --arch i386 --thin_type bare

debian-edu-ltsp-initrd

PXE stands for Preboot eXecution Environment. Debian Edu now uses the iPXE implementation for easier LTSP integration.

d-i     apt-setup/local1/repository string      http://example.org/debian stable main contrib non-free
d-i     apt-setup/local1/comment string         Example Software Repository
d-i     apt-setup/local1/source boolean         true
d-i     apt-setup/local1/key    string          http://example.org/key.asc

The debian-edu-config package comes with a tool which helps in changing the network from 10.0.0.0/8 to something else. Have a look at /usr/share/debian-edu-config/tools/subnet-change. It is intended for use just after installation on the main server, to update LDAP and other files that need to be edited to change the subnet.

Note that changing to one of the subnets already used elsewhere in Debian Edu will not work. 192.168.0.0/24 and 192.168.1.0/24 are already set up as LTSP client networks. Changing to these subnets will require manual editing of configuration files to remove duplicate entries.

There is no easy way to change the DNS domain name. Changing it would require changes to both the LDAP structure and several files in the main server file system. There is also no easy way to change the host and DNS name of the main server (tjener.intern). To do so would also require changes to LDAP and files in the main server and client file system. In both cases the Kerberos setup would have to be changed, too.

Choosing the LTSP server profile or the combined server profile also installs the xrdp and x2goserver packages.

 #!/bin/bash
 set -e
  if [[ $UID -ne 0 ]] ; then  
     if ! groups | egrep -q sudo ; then
         echo "ERROR: You need to be root or a sudo group member."
         exit 1
     fi
 fi
 if ! egrep -q  ^deb-src /etc/apt/sources.list ; then
     echo "ERROR: Make sure /etc/apt/sources.list contains a deb-src line."
     exit 1
 fi
 TMP=$(mktemp -d)
 PULSE_UPSTREAM_VERSION="$(dpkg-query -W -f='${source:Upstream-Version}' pulseaudio)"
 XRDP_UPSTREAM_VERSION="$(dpkg-query -W -f='${source:Upstream-Version}' xrdp)"
 sudo apt -q update
 sudo apt -q install dpkg-dev
 cd $TMP
 apt -q source pulseaudio xrdp
 sudo apt -q build-dep pulseaudio xrdp
 cd pulseaudio-$PULSE_UPSTREAM_VERSION/
 ./configure
 cd $TMP/xrdp-$XRDP_UPSTREAM_VERSION/sesman/chansrv/pulse/
 sed -i 's/^PULSE/#PULSE/' Makefile
 sed -i "/#PULSE_DIR/a \
 PULSE_DIR = $TMP/pulseaudio-$PULSE_UPSTREAM_VERSION" Makefile
 make
 sudo cp *.so /usr/lib/pulse-$PULSE_UPSTREAM_VERSION/modules/
 sudo chmod 644 /usr/lib/pulse-$PULSE_UPSTREAM_VERSION/modules/module-xrdp*
 sudo service xrdp restart

The freeRADIUS server could be used to provide secure network connections. For this to work, install the freeradius and winbind packages on the main server and run /usr/share/debian-edu-config/tools/setup-freeradius-server to generate a basic, site specific configuration. This way, both EAP-TTLS/PAP and PEAP-MSCHAPV2 methods are enabled. All configuration is contained in the script itself to facilitate site specific adjustments. See the freeRADIUS homepage for details.

Additional configuration is needed to

End user devices need to be configured properly, these devices need to be PIN protected for the use of EAP (802.1x) methods. Users should also be educated to install the freeradius CA certificate on their devices to be sure to connect to the right server. This way their password can't be catched in case of a malicious server. The site specific certificate is available on the internal network.

Please note that configuring end user devices will be a real challenge due to the variety of devices. For Windows devices an installer script could be created, for Apple devices a mobileconfig file. In both cases the freeRADIUS CA certificate can be integrated, but OS specific tools are needed to create the scripts.

Connections to a user's home directory and to additional site specific shares (if configured) are possible for devices running Linux, Android, macOS, iOS, iPadOS, Chrome OS or Windows. For example, Android based devices require a file manager with SMB2/SMB3 support, also known as LAN access. X-plore or Total Commander with LAN plugin might be a good choice.

Use \\tjener\<username> or smb://tjener/<username> to access the home directory.

stable/education-development is a meta package depending on a lot of programming tools. Please note that almost 2 GiB of disk space is needed if this package is installed. For more details (maybe to install only a few packages), see the Debian Edu Development packages page.

Warning: make sure you know the status of the laws about monitoring and restricting computer users' activities in your jurisdiction.

Some schools use control tools like Epoptes or Veyon to supervise their students. See also: Epoptes Homepage and Veyon Homepage.

Some schools use Squidguard or e2guardian to restrict Internet access.

Every user should change her or his password by using GOsa². To do so, just use a browser and go to https://www/gosa/.

Using GOsa² to change the password ensures that passwords for Kerberos (krbPrincipalKey), LDAP (userPassword) and Samba are the same.

Changing passwords using PAM is working also at the GDM login prompt, but this will only update the Kerberos password, and not the Samba and GOsa² (LDAP) password. So after you changed your password at the login prompt, you really should also change it using GOsa².

Standalone Java applications are supported out of the box by the OpenJDK Java runtime.

All users can send and receive mails within the internal network; certificates are provided to allow TLS secured connections. To allow mail outside the internal network, the administrator needs to configure the mailserver exim4 to suit the local situation, starting with dpkg-reconfigure exim4-config.

Every user who wants to use Thunderbird needs to configure it as follows. For a user with username jdoe the internal email address is jdoe@postoffice.intern.

Most of the time, the developer mailing list is our main medium for communication, though we also have #debian-edu on irc.debian.org and even, sometimes, real gatherings, where we meet each other in person.

A good way to learn what is happening in the development of Debian Edu is to subscribe to the commit mailinglist.

Debian Edu uses the Debian Bug Tracking System (BTS). View existing bug reports and feature requests or create new ones. Please report all bugs against the package debian-edu-config. Take a look at How To Report Bugs for more information on bug reporting in Debian Edu.

This document needs your help! First and foremost, it is not finished yet: if you read it, you will notice various FIXMEs within the text. If you happen to know (a bit of) what needs to be explained there, please consider sharing your knowledge with us.

The source of the text is a wiki and can be edited with a simple webbrowser. Just go to https://wiki.debian.org/DebianEdu/Documentation/Bookworm/ and you can contribute easily. Note: a user account is needed to edit the pages; you may need to create a wiki user account first.

Another very good way to contribute and to help users is by translating software and documentation. Information on how to translate this document can be found in the translations chapter of this book. Please consider helping the translation effort of this book!

Lists of companies providing professional support are available from https://wiki.debian.org/DebianEdu/Help/ProfessionalHelp.

Copyright (C) 2007-2021 Holger Levsen < holger@layer-acht.org > and others, see the Copyright for the full list of copyright owners.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Version 2, June 1991

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0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The "Program", below, refers to any such program or work, and a "work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language. (Hereinafter, translation is included without limitation in the term "modification".) Each licensee is addressed as "you".

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END OF TERMS AND CONDITIONS

The following Debian Edu releases were made further in the past:

A complete and detailed overview about older releases is contained in Appendix C of the Jessie manual; or see the related release manuals on the release manuals page.