[systemd-devel] [ANNOUNCE] systemd 215
lennart at poettering.net
Thu Jul 3 13:59:57 PDT 2014
A lot of work to make factory reset, stateless systems and disconnected
updates working. A lot of networkd love (dhcp4 server!) and coredumpctl
is now finally really really useful.
CHANGES WITH 215:
* A new tool systemd-sysusers has been added. This tool
creates system users and groups in /etc/passwd and
/etc/group, based on static declarative system user/group
definitions in /usr/lib/sysusers.d/. This is useful to
enable factory resets and volatile systems that boot up with
an empty /etc directory, and thus need system users and
groups created during early boot. systemd now also ships
with two default sysusers.d/ files for the most basic
users and groups systemd and the core operating system
* A new tmpfiles snippet has been added that rebuilds the
essential files in /etc on boot, should they be missing.
* A directive for ensuring automatic clean-up of
/var/cache/man/ has been removed from the default
configuration. This line should now be shipped by the man
implementation. The necessary change has been made to the
man-db implementation. Note that you need to update your man
implementation to one that ships this line, otherwise no
automatic clean-up of /var/cache/man will take place.
* A new condition ConditionNeedsUpdate= has been added that
may conditionalize services to only run when /etc or /var
are "older" than the vendor operating system resources in
/usr. This is useful for reconstructing or updating /etc
after an offline update of /usr or a factory reset, on the
next reboot. Services that want to run once after such an
update or reset should use this condition and order
themselves before the new systemd-update-done.service, which
will mark the two directories as fully updated. A number of
service files have been added making use of this, to rebuild
the udev hardware database, the journald message catalog and
dynamic loader cache (ldconfig). The systemd-sysusers tool
described above also makes use of this now. With this in
place it is now possible to start up a minimal operating
system with /etc empty cleanly. For more information on the
concepts involved see this recent blog story:
* A new system group "input" has been introduced, and all
input device nodes get this group assigned. This is useful
for system-level software to get access to input devices. It
complements what is already done for "audio" and "video".
* systemd-networkd learnt minimal DHCPv4 server support in
addition to the existing DHCPv4 client support. It also
learnt DHCPv6 client and IPv6 Router Solicitation client
support. The DHCPv4 client gained support for static routes
passed in from the server. Note that the [DHCPv4] section
known in older systemd-networkd versions has been renamed to
[DHCP] and is now also used by the DHCPv6 client. Existing
.network files using settings of this section should be
updated, though compatibility is maintained. Optionally, the
client hostname may now be sent to the DHCP server.
* networkd gained support for vxlan virtual networks as well
as tun/tap and dummy devices.
* networkd gained support for automatic allocation of address
ranges for interfaces from a system-wide pool of
addresses. This is useful for dynamically managing a large
number of interfaces with a single network configuration
file. In particular this is useful to easily assign
appropriate IP addresses to the veth links of a large number
of nspawn instances.
* RPM macros for processing sysusers, sysctl and binfmt
drop-in snippets at package installation time have been
* The /etc/os-release file should now be placed in
/usr/lib/os-release. The old location is automatically
created as symlink. /usr/lib is the more appropriate
location of this file, since it shall actually describe the
vendor operating system shipped in /usr, and not the
configuration stored in /etc.
* .mount units gained a new boolean SloppyOptions= setting
that maps to mount(8)'s -s option which enables permissive
parsing of unknown mount options.
* tmpfiles learnt a new "L+" directive which creates a symlink
but (unlike "L") deletes a pre-existing file first, should
it already exist and not already be the correct
symlink. Similar, "b+", "c+" and "p+" directives have been
added as well, which create block and character devices, as
well as fifos in the filesystem, possibly removing any
pre-existing files of different types.
* For tmpfiles' "L", "L+", "C" and "C+" directives the final
'argument' field (which so far specified the source to
symlink/copy the files from) is now optional. If omitted the
same file os copied from /usr/share/factory/ suffixed by the
full destination path. This is useful for populating /etc
with essential files, by copying them from vendor defaults
shipped in /usr/share/factory/etc.
* A new command "systemctl preset-all" has been added that
applies the service preset settings to all installed unit
files. A new switch --preset-mode= has been added that
controls whether only enable or only disable operations
shall be executed.
* A new command "systemctl is-system-running" has been added
that allows checking the overall state of the system, for
example whether it is fully up and running.
* When the system boots up with an empty /etc, the equivalent
to "systemctl preset-all" is executed during early boot, to
make sure all default services are enabled after a factory
* systemd now contains a minimal preset file that enables the
most basic services systemd ships by default.
* Unit files' [Install] section gained a new DefaultInstance=
field for defining the default instance to create if a
template unit is enabled with no instance specified.
* A new passive target cryptsetup-pre.target has been added
that may be used by services that need to make they run and
finish before the first LUKS cryptographic device is set up.
* The /dev/loop-control and /dev/btrfs-control device nodes
are now owned by the "disk" group by default, opening up
access to this group.
* systemd-coredump will now automatically generate a
stack trace of all core dumps taking place on the system,
based on elfutils' libdw library. This stack trace is logged
to the journal.
* systemd-coredump may now optionally store coredumps directly
on disk (in /var/lib/systemd/coredump, possibly compressed),
instead of storing them unconditionally in the journal. This
mode is the new default. A new configuration file
/etc/systemd/coredump.conf has been added to configure this
and other parameters of systemd-coredump.
* coredumpctl gained a new "info" verb to show details about a
specific coredump. A new switch "-1" has also been added
that makes sure to only show information about the most
recent entry instead of all entries. Also, as the tool is
generally useful now the "systemd-" prefix of the binary
name has been removed. Distributions that want to maintain
compatibility with the old name should add a symlink from
the old name to the new name.
* journald's SplitMode= now defaults to "uid". This makes sure
that unprivileged users can access their own coredumps with
coredumpctl without restrictions.
* New kernel command line options "systemd.wants=" (for
pulling an additional unit during boot), "systemd.mask="
(for masking a specific unit for the boot), and
"systemd.debug-shell" (for enabling the debug shell on tty9)
have been added. This is implemented in the new generator
* systemd-nspawn will now by default filter a couple of
syscalls for containers, among them those required for
kernel module loading, direct x86 IO port access, swap
management, and kexec. Most importantly though
open_by_handle_at() is now prohibited for containers,
closing a hole similar to a recently discussed vulnerability
in docker regarding access to files on file hierarchies the
container should normally not have access to. Note that for
nspawn we generally make no security claims anyway (and
this is explicitly documented in the man page), so this is
just a fix for one of the most obvious problems.
* A new man page file-hierarchy(7) has been added that
contains a minimized, modernized version of the file system
layout systemd expects, similar in style to the FHS
specification or hier(5). A new tool systemd-path(1) has
been added to query many of these paths for the local
machine and user.
* Automatic time-based clean-up of $XDG_RUNTIME_DIR is no
longer done. Since the directory now has a per-user size
limit, and is cleaned on logout this appears unnecessary,
in particular since this now brings the lifecycle of this
directory closer in line with how IPC objects are handled.
* systemd.pc now exports a number of additional directories,
including $libdir (which is useful to identify the library
path for the primary architecture of the system), and a
couple of drop-in directories.
* udev's predictable network interface names now use the dev_port
sysfs attribute, introduced in linux 3.15 instead of dev_id to
distinguish between ports of the same PCI function. dev_id should
only be used for ports using the same HW address, hence the need
* machined has been updated to export the OS version of a
container (read from /etc/os-release and
/usr/lib/os-release) on the bus. This is now shown in
"machinectl status" for a machine.
* A new service setting RestartForceExitStatus= has been
added. If configured to a set of exit signals or process
return values, the service will be restarted when the main
daemon process exits with any of them, regardless of the
* systemctl's -H switch for connecting to remote systemd
machines has been extended so that it may be used to
directly connect to a specific container on the
host. "systemctl -H root at foobar:waldi" will now connect as
user "root" to host "foobar", and then proceed directly to
the container named "waldi". Note that currently you have to
authenticate as user "root" for this to work, as entering
containers is a privileged operation.
Contributions from: Andreas Henriksson, Benjamin Steinwender,
Carl Schaefer, Christian Hesse, Colin Ian King, Cristian
Rodríguez, Daniel Mack, Dave Reisner, David Herrmann, Eugene
Yakubovich, Filipe Brandenburger, Frederic Crozat, Hristo
Venev, Jan Engelhardt, Jonathan Boulle, Kay Sievers, Lennart
Poettering, Luke Shumaker, Mantas Mikulėnas, Marc-Antoine
Perennou, Marcel Holtmann, Michael Marineau, Michael Olbrich,
Michał Bartoszkiewicz, Michal Sekletar, Patrik Flykt, Ronan Le
Martret, Ronny Chevalier, Ruediger Oertel, Steven Noonan,
Susant Sahani, Thadeu Lima de Souza Cascardo, Thomas Hindoe
Paaboel Andersen, Tom Gundersen, Tom Hirst, Umut Tezduyar
Lindskog, Uoti Urpala, Zbigniew Jędrzejewski-Szmek
-- Berlin, 2014-07-03
Lennart Poettering, Red Hat
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