When creating a custom appliance (as described here https://www.turnkeylinux.org/docs/howto-build-isos-with-tkldev) I got an error message, that the package "jitterentropy-rngd" was not found.

Known bug?

Preparing to unpack .../linux-image-amd64_4.9+80+deb9u9_amd64.deb ...
Unpacking linux-image-amd64 (4.9+80+deb9u9) ...
Setting up linux-image-4.9.0-11-amd64 (4.9.189-3+deb9u2) ...
I: /vmlinuz.old is now a symlink to boot/vmlinuz-4.9.0-11-amd64
I: /initrd.img.old is now a symlink to boot/initrd.img-4.9.0-11-amd64
I: /vmlinuz is now a symlink to boot/vmlinuz-4.9.0-11-amd64
I: /initrd.img is now a symlink to boot/initrd.img-4.9.0-11-amd64
/etc/kernel/postinst.d/initramfs-tools:

Warning: Deferring update-initramfs -c -t -k 4.9.0-11-amd64 -b /boot
Setting up linux-image-amd64 (4.9+80+deb9u9) ...
W: --force-yes is deprecated, use one of the options starting with --allow instead.
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package jitterentropy-rngd
Traceback (most recent call last):
  File "/usr/lib/fab/wrapper.py", line 34, in <module>
    CliWrapper.main()
  File "/usr/lib/python2.7/dist-packages/pyproject.py", line 388, in main
    commands.run(name, args)
  File "/usr/lib/python2.7/dist-packages/pyproject.py", line 261, in run
    command.module.main()
  File "/usr/lib/fab/pylib/cmd_install.py", line 129, in main
    installer.install(packages, ignore_errors)
  File "/usr/lib/fab/pylib/installer.py", line 267, in install
    self._install(packages, ignore_errors)
  File "/usr/lib/fab/pylib/installer.py", line 137, in _install
    self.chroot.system("apt-get", *(args + packages))
  File "/usr/lib/python2.7/dist-packages/chroot.py", line 80, in system
    executil.system(*self._prepare_command(*command))
  File "/usr/lib/python2.7/dist-packages/executil.py", line 56, in system
    raise ExecError(command, exitcode)
executil.ExecError: non-zero exitcode (100) for command: chroot '/turnkey/fab/products/core/build/root.build'  'sh'  '-c'  "env -i  'TERM=xterm'  'AMD64=y'  'DEBIAN_FRONTEND=noninteractive'  'HOSTNAME=core'  'WEBMIN_FW_TCP_INCOMING=22 80 443 12320 12321'  'FAB_ARCH=amd64'  'DEBIAN=y'  'FAB_HTTP_PROXY=http://127.0.0.1:8124'  'DEBIAN_PRIORITY=critical'  'HOME=/root'  'RELEASE=debian/stretch'  'PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/bin:/usr/sbin'  'CODENAME=stretch'  'LC_ALL=C'  'DISTRO=debian' apt-get 'install'  '--force-yes'  '--assume-yes'  'libgcc1'  'libnet-ssleay-perl'  'lsb-base'  'kbd'  'webmin-filemin'  'findutils'  'rsyslog'  'sensible-utils'  'systemd'  'util-linux'  'libncursesw5'  'dtach'  'whiptail'  'less'  'sysv-rc'  'shellinabox'  'dpkg'  'iptables'  'libpam-modules'  'liblzma5'  'initramfs-tools-core'  'cpio'  'bash-completion'  'libacl1'  'debian-archive-keyring'  'startpar'  'libncurses5'  'grep'  'libgpg-error0'  'acpi-support-base'  'libpam0g'  'bind9-host'  'webmin-updown'  'stunnel4'  'libpam-modules-bin'  'webmin'  'psmisc'  'e2fslibs'  'tklbam'  'net-tools'  'hubdns'  'systemd-sysv'  'udhcpc'  'libfile-mimeinfo-perl'  'debconf'  'webmin-authentic-theme'  'sysvinit-utils'  'webmin-sshd'  'adduser'  'syslinux-common'  'webmin-passwd'  'udev'  'cron'  'sed'  'live-tools'  'mktemp'  'kmod'  'rsync'  'localepurge'  'nano'  'isolinux'  'python3-bottle'  'libselinux1'  'dehydrated'  'passwd'  'jitterentropy-rngd'  'libsmartcols1'  'webmin-net'  'libpam-runtime'  'libss2'  'live-boot-initramfs-tools'  'ntp'  'screen'  'libpcre3'  'libdebconfclient0'  'libmount1'  'libattr1'  'webmin-useradmin'  'wget'  'libbz2-1.0'  'python3-requests'  'bash'  'libsystemd0'  'mawk'  'di-live'  'webmin-software'  'login'  'libuuid1'  'linux-base'  'libklibc'  'etckeeper'  'authbind'  'python3-dialog'  'gpgv'  'apt'  'lsb-release'  'init-system-helpers'  'libc-bin'  'syslinux'  'tar'  'perl-openssl-defaults'  'liblz4-1'  'cron-apt'  'webmin-syslog'  'netbase'  'libaudit-common'  'webmin-raid'  'turnkey-sysinfo'  'webmin-custom'  'klibc-utils'  'libsepol1'  'traceroute'  'gzip'  'libudev1'  'bsd-mailx'  'libgcrypt20'  'hdparm'  'debianutils'  'bsdutils'  'webmin-tklbam'  'git'  'ncurses-base'  'confconsole'  'iputils-ping'  'webmin-fdisk'  'eject'  'mount'  'lvm2'  'initscripts'  'resolvconf'  'libdb5.3'  'gnupg'  'libapt-pkg5.0'  'procps'  'ethtool'  'libprocps6'  'live-boot'  'man-db'  'libsemanage-common'  'dash'  'logrotate'  'unzip'  'fail2ban'  'file'  'base-files'  'curl'  'initramfs-tools'  'libtinfo5'  'libfdisk1'  'hostname'  'libaudit1'  'coreutils'  'libsemanage1'  'libkmod2'  'webmin-fail2ban'  'webmin-shell'  'libc-l10n'  'insserv'  'ncurses-bin'  'gcc-6-base'  'libcap-ng0'  'multiarch-support'  'iproute2'  'zlib1g'  'libc6'  'webmin-firewall'  'libustr-1.0-1'  'libstdc++6'  'libcomerr2'  'postfix'  'diffutils'  'ncurses-term'  'inithooks'  'e2fsprogs'  'base-passwd'  'perl-base'  'locales'  'ifupdown'  'vim-tiny'  'webmin-lvm'  'libblkid1'  'webmin-postfix'  'ssh'"
/usr/share/fab/product.mk:535: recipe for target 'build/stamps/root.build' failed