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Debian Installation for Control Freaks

Installation of embedded systems present a unique circumstance, because one usually wants to create a system that can be replicated identically.  You may also have to save the whole repository in a Configuration Management system in order to keep strict control over the file versions, so you can do an update once a year or three.

The Debian/Ubuntu installer typically starts from an ISO image on a CD or USB memory stick, but thereafter wants to go online to consult a mirror server somewhere else in the world.  The moment that happens, you lose control over what exactly is installed on your machine.

Make a Bootable USB Stick

For the last couple years, Ubuntu ISO files are dual mode - bootable on CD and USB, same as Red Hat.

Download a server ISO from a mirror server, e.g. Yandex:
http://mirror.yandex.ru/ubuntu-releases/

Plug the stick in and check the device name with dmesg!
# dmesg

Write it to a USB stick with Data Definition:
# dd if=filename.iso of=/dev/sdb bs=1M

We are Paranoid Control Freaks right?  Get the MD5SUM file from a different mirror server and run the check on the downloaded ISO files:
# md5sum -c MD5SUMS

...and if you are wearing a tin-foil or armadillo hat, use the SHA256 sums also.

Please Sir, can I have more?

So, after you performed a minimal install and the embedded system is running, how can you install more things from the CD image without going online?

The best solution is to create a private mirror server, but one can also install offline using the original ISO images only, by making a few tweaks in the /etc/apt/sources.list file.

If a system has a large hard disk, then one can copy all the ISO files to the HDD and then permanently loop mount them in a fixed place in /mnt using the fstab file.  After that, a suitable file:// entry in the sources list will cause apt, dpkg and aptitude to refer to them instead of going online all the time.

USB Stick Repository

If the distribution ISO files are on a USB memory stick, then they are not always available, but you can ensure that they will always have the same path if you give the stick a proper volume label using gparted, such as USBISO for argument's sake.  The stick will then always mount with the path /run/media/username/USBISO, which should be good enough that you can make a script of the following.

This works better with Debian, for which you can get the complete repository as a series of ISO files.

Make a mount point:
mkdir /mnt/mountpoint

Mount the downloaded ISO file:
mount -t iso9660 -o loop /media/run/username/volumelabel/distrofile.iso /mnt/mountpoint

Add the following line to the top of /etc/apt/sources.list and comment out everything else:
deb file://mnt/mountpoint distroname main restricted

(Of course, use your own username, volumelabel, distrofile, mountpoint and distroname)

From now on, provided that you can find the little stick again (possibly just leave it plugged in forever), you can mount it and when you run apt-get, it will get things from the ISO image file, not some obscure server elsewhere in the world.

Mirror, Mirror on The Wall

Once you get your own web server running with lighttpd and mounted an ISO file with the whole distribution, then simply edit the /etc/apt/sources.list file again and add a suitable deb http://yourmirroripaddress/pathtofiles distroname main restricted entry, same as the other examples in that file.

Just be sure to comment out everything else that doesn't apply and from then on, apt-get will pull files off your web server (More information on mirroring at the bottom of this page here: http://www.aeronetworks.ca/2016/02/mirror-mirror-on-wall.html).

Debian/Ubuntu/Fedora *nix Confusion

My  mirror server happens to be a Fedora Linux machine and it is also used to serve the preseed auto-response file and .deb packages for an automated Ubuntu LTS installation, so the descriptions below are a little mixed up - dnf is the Fedora install program and apt-get is the Debian/Ubuntu install program.  Kickstart is for Redhat and Preseed is for Debian.

Vive la difference.

Configure lighttpd on Fedora

For automated installation, a web server is required to serve the Debian preseed file and the .deb packages.
Install:

# dnf install -y lighttpd

Edit /etc/lighttpd/lighttpd.conf:

var.server_root = "/var/www"

Make a directory:

#mkdir /var/www/htdocs

Make the file /var/www/htdocs/index.html

Start the server:

# systemctl enable lighttpd.service
systemctl start lighttpd.service

Test the server:

$ firefox http://localhost

Configure dhcpd on Fedora

A DHCP server is necessary to provide an IP address to the new system.  It can also be used to provide the file server name and path to the preseed file, but that level of automation can be a little dangerous, since one could then accidentally re-install a system.

Install:

# dnf install -y dhcpd-server

Edit file /etc/dhcp/dhcpd.conf:
default-lease-time 600;
max-lease-time 7200;
option subnet-mask 255.255.255.0;
option broadcast-address 192.168.111.255;
option routers 192.168.111.254;
option domain-name "example.com";
option domain-name-servers 192.168.111.1;

subnet 192.168.111.0 netmask 255.255.255.0 {
range 192.168.111.200 192.168.111.250;
}

Start the server:

# systemctl enable dhcpd.service
# 
systemctl start dhcpd.service

Configure Standard Ethernet Device Names on Fedora

Fedora uses weird device names for the ethernet ports which break my scripts.  Force Fedora to name the ports eth0..n with a small change in the grub configuration file.

Edit file /etc/default/grub:

Add to the end of GRUB_CMDLINE_LINUX, net.ifnames=0

Configure grub:
# grub2-mkconfig -o /boot/grub2/grub.cfg

Edit /etc/sysonfig/ifcfg-ewhatever:

# cd /etc/sysconfig/network-scripts/

# 
nano ifcfg-whatever

Change the name of whatever to eth0


# reboot

Disable The Fedora Firewall

To let web server requests through, flush the iptables rules:

# iptables -F
# systemctl stop firewalld.service
# systemctl disable firewalld.service

Mount The ISO Files on Fedora

Copy the server, desktop and source ISO files to /home/herman/ISO, then make mount points in /var/www/htdocs:

# mkdir /var/www/htdocs/server

Add a mount line to /etc/fstab for each ISO file:

/home/herman/ISO/ubuntu-14.04.4-server-amd64+mac.iso /var/www/htdocs/server iso9660 loop 0 0

Mount them all:

# mount -a

Now the web server can serve the contents of the ISO files!

(Note that Fedora runs SELinux and if you would put a symlink to an area outside /var/www, then you need to add a rule and relabel with semanager, else you will get perplexing 403 Forbidden errors.)

Auto-install An Ubuntu Embedded System Or Server

Put the preseed file in the /var/www/htdocs root of the web server and as a minimum, replace the "file=..." in the boot prompt of the new computer to be installed with "auto url=http://webserveripaddress/preseedfilename".  Which is a bit easier said than done.

Two Boot Prompts - Cannot Find Kernel

The problem with preseeding, is that it only reads the file after the network setup is done, with the result that the first bunch of entries in the preseed file regarding the keyboard, screen, hostname, domainname and ethernet port, need to be specified on the boot command line (or you have to answer the prompts interactively).

The other problem is that the system has two different boot prompts. Yes, you heard that right.  Somebody deserves seven lashes with a wet noodle for this one.

Set the BIOS so the thing can boot off USB and stick an Ubuntu server ISO thingy in.  Boot up and wait for the language selection screenDo not press Esc during boot.  The blank boot prompt that you will get early on after pressing escape is the wrong one.  

No matter what you type in the blank boot prompt, it will always result in a Cannot find kernel whatever errorThat was a serious time waster and prompted me to write all this. 

Wait For The Language Screen

Once at the language screen, wait a little bit for good measure, then press Esc. You will then get back to the install menu.  Press F6 and then Esc to get a boot prompt with a default string in it looking like this:
Boot: file=/cdrom/preseed/ubuntu-server.seed vga=788 initrd=/install/initrd.gz quiet --


Edit that string to look like this (backspace deletes):
Boot: auto url=http://192.168.111.1/preseed.txt locale=en_US console-setup/ask_detect=false keyboard-configuration/layoutcode=us interface=eth0 hostname=test initrd=/install/initrd.gz quiet --

Now press Enter and it should start with only a few remaining questions and eventually read the preseed.txt file and execute it.

Run tcpdump -nlX -i eth0 on the server to see what is going on.

Preseed File Example For An Ubuntu Embedded System Or Server

This is a minimal server install.  Change the username and password.  You can add more packages at the very bottom.

#### Contents of the preconfiguration file (for squeeze)
### Localization
# Preseeding only locale sets language, country and locale.
d-i debian-installer/locale string en_US

# The values can also be preseeded individually for greater flexibility.
#d-i debian-installer/language string en
#d-i debian-installer/country string NL
#d-i debian-installer/locale string en_GB.UTF-8
# Optionally specify additional locales to be generated.
#d-i localechooser/supported-locales en_US.UTF-8, nl_NL.UTF-8

# Keyboard selection.
# Disable automatic (interactive) keymap detection.
d-i console-setup/ask_detect boolean false
#d-i keyboard-configuration/modelcode string pc105
d-i keyboard-configuration/layoutcode string us
# To select a variant of the selected layout (if you leave this out, the
# basic form of the layout will be used):
#d-i keyboard-configuration/variantcode string dvorak

### Network configuration
# Disable network configuration entirely. This is useful for cdrom
# installations on non-networked devices where the network questions,
# warning and long timeouts are a nuisance.
#d-i netcfg/enable boolean false

# netcfg will choose an interface that has link if possible. This makes it
# skip displaying a list if there is more than one interface.
#d-i netcfg/choose_interface select auto

# To pick a particular interface instead:
d-i netcfg/choose_interface select eth0

# If you have a slow dhcp server and the installer times out waiting for
# it, this might be useful.
d-i netcfg/dhcp_timeout string 60

# If you prefer to configure the network manually, uncomment this line and
# the static network configuration below.
#d-i netcfg/disable_autoconfig boolean true

# If you want the preconfiguration file to work on systems both with and
# without a dhcp server, uncomment these lines and the static network
# configuration below.
d-i netcfg/dhcp_failed note
d-i netcfg/dhcp_options select Configure network manually

# Static network configuration.
d-i netcfg/get_nameservers string 192.168.111.211
d-i netcfg/get_ipaddress string 192.168.111.211
d-i netcfg/get_netmask string 255.255.255.0
d-i netcfg/get_gateway string 192.168.111.211
d-i netcfg/confirm_static boolean true

# Any hostname and domain names assigned from dhcp take precedence over
# values set here. However, setting the values still prevents the questions
# from being shown, even if values come from dhcp.
d-i netcfg/get_hostname string gcu
d-i netcfg/get_domain string example.com

# Disable that annoying WEP key dialog.
d-i netcfg/wireless_wep string
# The wacky dhcp hostname that some ISPs use as a password of sorts.
#d-i netcfg/dhcp_hostname string radish

# If non-free firmware is needed for the network or other hardware, you can
# configure the installer to always try to load it, without prompting. Or
# change to false to disable asking.
#d-i hw-detect/load_firmware boolean true

### Network console
# Use the following settings if you wish to make use of the network-console
# component for remote installation over SSH. This only makes sense if you
# intend to perform the remainder of the installation manually.
#d-i anna/choose_modules string network-console
#d-i network-console/password password r00tme
#d-i network-console/password-again password r00tme
# Use this instead if you prefer to use key-based authentication
#d-i network-console/authorized_keys_url http://host/authorized_keys

### Mirror settings
# If you select ftp, the mirror/country string does not need to be set.
#d-i mirror/protocol string ftp
d-i mirror/country string manual
d-i mirror/http/hostname string 192.168.111.1
d-i mirror/http/directory string /server
d-i mirror/http/proxy ""

# Alternatively: by default, the installer uses CC.archive.ubuntu.com where
# CC is the ISO-3166-2 code for the selected country. You can preseed this
# so that it does so without asking.
#d-i mirror/http/mirror select CC.archive.ubuntu.com

# Suite to install.
#d-i mirror/suite string squeeze
# Suite to use for loading installer components (optional).
#d-i mirror/udeb/suite string squeeze
# Components to use for loading installer components (optional).
#d-i mirror/udeb/components multiselect main, restricted

### Clock and time zone setup
# Controls whether or not the hardware clock is set to UTC.
d-i clock-setup/utc boolean true

# You may set this to any valid setting for $TZ; see the contents of
# /usr/share/zoneinfo/ for valid values.
d-i time/zone string Asia/Dubai

# Controls whether to use NTP to set the clock during the install
d-i clock-setup/ntp boolean false
# NTP server to use. The default is almost always fine here.
#d-i clock-setup/ntp-server string ntp.example.com

### Partitioning
## Partitioning example
# If the system has free space you can choose to only partition that space.
# This is only honoured if partman-auto/method (below) is not set.
# Alternatives: custom, some_device, some_device_crypto, some_device_lvm.
#d-i partman-auto/init_automatically_partition select biggest_free

# Alternatively, you may specify a disk to partition. If the system has only
# one disk the installer will default to using that, but otherwise the device
# name must be given in traditional, non-devfs format (so e.g. /dev/hda or
# /dev/sda, and not e.g. /dev/discs/disc0/disc).
# For example, to use the first SCSI/SATA hard disk:
d-i partman-auto/disk string /dev/sda
# In addition, you'll need to specify the method to use.
# The presently available methods are:
# - regular: use the usual partition types for your architecture
# - lvm:     use LVM to partition the disk
# - crypto:  use LVM within an encrypted partition
d-i partman-auto/method string regular

# If one of the disks that are going to be automatically partitioned
# contains an old LVM configuration, the user will normally receive a
# warning. This can be preseeded away...
d-i partman-lvm/device_remove_lvm boolean true
# The same applies to pre-existing software RAID array:
d-i partman-md/device_remove_md boolean true
# And the same goes for the confirmation to write the lvm partitions.
d-i partman-lvm/confirm boolean true

# For LVM partitioning, you can select how much of the volume group to use
# for logical volumes.
#d-i partman-auto-lvm/guided_size string max
#d-i partman-auto-lvm/guided_size string 10GB
#d-i partman-auto-lvm/guided_size string 50%

# You can choose one of the three predefined partitioning recipes:
# - atomic: all files in one partition
# - home:   separate /home partition
# - multi:  separate /home, /usr, /var, and /tmp partitions
d-i partman-auto/choose_recipe select atomic

# Or provide a recipe of your own...
# If you have a way to get a recipe file into the d-i environment, you can
# just point at it.
#d-i partman-auto/expert_recipe_file string /hd-media/recipe

# If not, you can put an entire recipe into the preconfiguration file in one
# (logical) line. This example creates a small /boot partition, suitable
# swap, and uses the rest of the space for the root partition:
#d-i partman-auto/expert_recipe string                         \
#      boot-root ::                                            \
#              40 50 100 ext3                                  \
#                      $primary{ } $bootable{ }                \
#                      method{ format } format{ }              \
#                      use_filesystem{ } filesystem{ ext3 }    \
#                      mountpoint{ /boot }                     \
#              .                                               \
#              500 10000 1000000000 ext3                       \
#                      method{ format } format{ }              \
#                      use_filesystem{ } filesystem{ ext3 }    \
#                      mountpoint{ / }                         \
#              .                                               \
#              64 512 300% linux-swap                          \
#                      method{ swap } format{ }                \
#              .

# If you just want to change the default filesystem from ext3 to something
# else, you can do that without providing a full recipe.
d-i partman/default_filesystem string ext4

# The full recipe format is documented in the file partman-auto-recipe.txt
# included in the 'debian-installer' package or available from D-I source
# repository. This also documents how to specify settings such as file
# system labels, volume group names and which physical devices to include
# in a volume group.

# This makes partman automatically partition without confirmation, provided
# that you told it what to do using one of the methods above.
d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select finish
d-i partman/confirm boolean true
d-i partman/confirm_nooverwrite boolean true

## Partitioning using RAID
# The method should be set to "raid".
#d-i partman-auto/method string raid
# Specify the disks to be partitioned. They will all get the same layout,
# so this will only work if the disks are the same size.
#d-i partman-auto/disk string /dev/sda /dev/sdb

# Next you need to specify the physical partitions that will be used.
#d-i partman-auto/expert_recipe string \
#      multiraid ::                                         \
#              1000 5000 4000 raid                          \
#                      $primary{ } method{ raid }           \
#              .                                            \
#              64 512 300% raid                             \
#                      method{ raid }                       \
#              .                                            \
#              500 10000 1000000000 raid                    \
#                      method{ raid }                       \
#              .

# Last you need to specify how the previously defined partitions will be
# used in the RAID setup. Remember to use the correct partition numbers
# for logical partitions. RAID levels 0, 1, 5, 6 and 10 are supported;
# devices are separated using "#".
# Parameters are:
# <raidtype> <devcount> <sparecount> <fstype> <mountpoint> \
#          <devices> <sparedevices>

#d-i partman-auto-raid/recipe string \
#    1 2 0 ext3 /                    \
#          /dev/sda1#/dev/sdb1       \
#    .                               \
#    1 2 0 swap -                    \
#          /dev/sda5#/dev/sdb5       \
#    .                               \
#    0 2 0 ext3 /home                \
#          /dev/sda6#/dev/sdb6       \
#    .

# For additional information see the file partman-auto-raid-recipe.txt
# included in the 'debian-installer' package or available from D-I source
# repository.

# This makes partman automatically partition without confirmation.
d-i partman-md/confirm boolean true
d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select finish
d-i partman/confirm boolean true
d-i partman/confirm_nooverwrite boolean true

## Controlling how partitions are mounted
# The default is to mount by UUID, but you can also choose "traditional" to
# use traditional device names, or "label" to try filesystem labels before
# falling back to UUIDs.
d-i partman/mount_style select label

### Base system installation
# Configure APT to not install recommended packages by default. Use of this
# option can result in an incomplete system and should only be used by very
# experienced users.
#d-i base-installer/install-recommends boolean false

# The kernel image (meta) package to be installed; "none" can be used if no
# kernel is to be installed.
d-i base-installer/kernel/image string linux-generic

### Account setup
# Skip creation of a root account (normal user account will be able to
# use sudo). The default is false; preseed this to true if you want to set
# a root password.
#d-i passwd/root-login boolean false
# Alternatively, to skip creation of a normal user account.
#d-i passwd/make-user boolean false

# Root password, either in clear text
#d-i passwd/root-password password r00tme
#d-i passwd/root-password-again password r00tme
# or encrypted using an MD5 hash.
#d-i passwd/root-password-crypted password [MD5 hash]

# To create a normal user account.
d-i passwd/user-fullname string JoePlumber
d-i passwd/username string joeplumber
# Normal user's password, either in clear text
d-i passwd/user-password password r00tme
d-i passwd/user-password-again password r00tme
# or encrypted using an MD5 hash.
#d-i passwd/user-password-crypted password [MD5 hash]
# Create the first user with the specified UID instead of the default.
#d-i passwd/user-uid string 1010
# The installer will warn about weak passwords. If you are sure you know
# what you're doing and want to override it, uncomment this.
d-i user-setup/allow-password-weak boolean true

# The user account will be added to some standard initial groups. To
# override that, use this.
d-i passwd/user-default-groups string audio cdrom video dialout usb

# Set to true if you want to encrypt the first user's home directory.
d-i user-setup/encrypt-home boolean false

### Apt setup
# You can choose to install restricted and universe software, or to install
# software from the backports repository.
d-i apt-setup/restricted boolean true
d-i apt-setup/universe boolean true
#d-i apt-setup/backports boolean true
# Uncomment this if you don't want to use a network mirror.
#d-i apt-setup/use_mirror boolean false
# Select which update services to use; define the mirrors to be used.
# Values shown below are the normal defaults.
#d-i apt-setup/services-select multiselect security
#d-i apt-setup/security_host string security.ubuntu.com
#d-i apt-setup/security_path string /ubuntu

# Additional repositories, local[0-9] available
d-i apt-setup/local0/repository string \
       http://192.168.111.1/server trusty main restricted
#d-i apt-setup/local0/comment string local server
# Enable deb-src lines
#d-i apt-setup/local0/source boolean true
# URL to the public key of the local repository; you must provide a key or
# apt will complain about the unauthenticated repository and so the
# sources.list line will be left commented out
#d-i apt-setup/local0/key string http://local.server/key

# By default the installer requires that repositories be authenticated
# using a known gpg key. This setting can be used to disable that
# authentication. Warning: Insecure, not recommended.
d-i debian-installer/allow_unauthenticated boolean true

### Package selection
tasksel tasksel/first multiselect ubuntu-server
#tasksel tasksel/first multiselect lamp-server, print-server
#tasksel tasksel/first multiselect kubuntu-desktop

# Individual additional packages to install
d-i pkgsel/include string openssh-server build-essential
# Whether to upgrade packages after debootstrap.
# Allowed values: none, safe-upgrade, full-upgrade
d-i pkgsel/upgrade select none

# Language pack selection
d-i pkgsel/language-packs multiselect en

# Policy for applying updates. May be "none" (no automatic updates),
# "unattended-upgrades" (install security updates automatically), or
# "landscape" (manage system with Landscape).
d-i pkgsel/update-policy select none

# Some versions of the installer can report back on what software you have
# installed, and what software you use. The default is not to report back,
# but sending reports helps the project determine what software is most
# popular and include it on CDs.
popularity-contest popularity-contest/participate boolean false

# By default, the system's locate database will be updated after the
# installer has finished installing most packages. This may take a while, so
# if you don't want it, you can set this to "false" to turn it off.
d-i pkgsel/updatedb boolean true

### Boot loader installation
# Grub is the default boot loader (for x86). If you want lilo installed
# instead, uncomment this:
#d-i grub-installer/skip boolean true
# To also skip installing lilo, and install no bootloader, uncomment this
# too:
#d-i lilo-installer/skip boolean true

# With a few exceptions for unusual partitioning setups, GRUB 2 is now the
# default. If you need GRUB Legacy for some particular reason, then
# uncomment this:
#d-i grub-installer/grub2_instead_of_grub_legacy boolean false

# This is fairly safe to set, it makes grub install automatically to the MBR
# if no other operating system is detected on the machine.
d-i grub-installer/only_debian boolean true

# This one makes grub-installer install to the MBR if it also finds some other
# OS, which is less safe as it might not be able to boot that other OS.
d-i grub-installer/with_other_os boolean false

# Alternatively, if you want to install to a location other than the mbr,
# uncomment and edit these lines:
#d-i grub-installer/only_debian boolean false
#d-i grub-installer/with_other_os boolean false
#d-i grub-installer/bootdev  string (hd0,0)
# To install grub to multiple disks:
#d-i grub-installer/bootdev  string (hd0,0) (hd1,0) (hd2,0)

# Optional password for grub, either in clear text
d-i grub-installer/password password r00tme
d-i grub-installer/password-again password r00tme
# or encrypted using an MD5 hash, see grub-md5-crypt(8).
#d-i grub-installer/password-crypted password [MD5 hash]

# Use the following option to add additional boot parameters for the
# installed system (if supported by the bootloader installer).
# Note: options passed to the installer will be added automatically.
#d-i debian-installer/add-kernel-opts string nousb

### Finishing up the installation
# During installations from serial console, the regular virtual consoles
# (VT1-VT6) are normally disabled in /etc/inittab. Uncomment the next
# line to prevent this.
#d-i finish-install/keep-consoles boolean true

# Avoid that last message about the install being complete.
d-i finish-install/reboot_in_progress note

# This will prevent the installer from ejecting the CD during the reboot,
# which is useful in some situations.
#d-i cdrom-detect/eject boolean false

# This is how to make the installer shutdown when finished, but not
# reboot into the installed system.d-i debian-installer/exit/halt boolean true
# This will power off the machine instead of just halting it.
#d-i debian-installer/exit/poweroff boolean true

### X configuration
# X can detect the right driver for some cards, but if you're preseeding,
# you override whatever it chooses. Still, vesa will work most places.
#xserver-xorg xserver-xorg/config/device/driver select vesa

# A caveat with mouse autodetection is that if it fails, X will retry it
# over and over. So if it's preseeded to be done, there is a possibility of
# an infinite loop if the mouse is not autodetected.
#xserver-xorg xserver-xorg/autodetect_mouse boolean true

# Monitor autodetection is recommended.
xserver-xorg xserver-xorg/autodetect_monitor boolean true
# Uncomment if you have an LCD display.
xserver-xorg xserver-xorg/config/monitor/lcd boolean true
# X has three configuration paths for the monitor. Here's how to preseed
# the "medium" path, which is always available. The "simple" path may not
# be available, and the "advanced" path asks too many questions.
xserver-xorg xserver-xorg/config/monitor/selection-method \
       select medium
xserver-xorg xserver-xorg/config/monitor/mode-list \
       select 1024x768 @ 60 Hz

### Preseeding other packages
# Depending on what software you choose to install, or if things go wrong
# during the installation process, it's possible that other questions may
# be asked. You can preseed those too, of course. To get a list of every
# possible question that could be asked during an install, do an
# installation, and then run these commands:
#   debconf-get-selections --installer > file
#   debconf-get-selections >> file


#### Advanced options
### Running custom commands during the installation
# d-i preseeding is inherently not secure. Nothing in the installer checks
# for attempts at buffer overflows or other exploits of the values of a
# preconfiguration file like this one. Only use preconfiguration files from
# trusted locations! To drive that home, and because it's generally useful,
# here's a way to run any shell command you'd like inside the installer,
# automatically.

# This first command is run as early as possible, just after
# preseeding is read.
#d-i preseed/early_command string anna-install some-udeb
# This command is run immediately before the partitioner starts. It may be
# useful to apply dynamic partitioner preseeding that depends on the state
# of the disks (which may not be visible when preseed/early_command runs).
#d-i partman/early_command \
#       string debconf-set partman-auto/disk "$(list-devices disk | head -n1)"
# This command is run just before the install finishes, but when there is
# still a usable /target directory. You can chroot to /target and use it
# directly, or use the apt-install and in-target commands to easily install
# packages and run commands in the target system.
#d-i preseed/late_command string apt-install zsh; in-target chsh -s /bin/zsh
d-i preseed/late_command string apt-install alsa-utils

d-i preseed/late_command string apt-install gstreamer
d-i preseed/late_command string apt-install minicom

As easy as borscht...

La voila!

Herman



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