<s>
systemd	B-Application
is	O
a	O
software	B-Application
suite	I-Application
that	O
provides	O
an	O
array	O
of	O
system	O
components	O
for	O
Linux	B-Application
operating	I-Application
systems	I-Application
.	O
</s>
<s>
The	O
main	O
aim	O
is	O
to	O
unify	O
service	O
configuration	O
and	O
behavior	O
across	O
Linux	B-Application
distributions	I-Application
.	O
</s>
<s>
Its	O
primary	O
component	O
is	O
a	O
"	O
system	O
and	O
service	B-Operating_System
manager	I-Operating_System
"	O
–	O
an	O
init	B-Operating_System
system	O
used	O
to	O
bootstrap	B-Application
user	B-Operating_System
space	I-Operating_System
and	O
manage	O
user	B-Operating_System
processes	I-Operating_System
.	O
</s>
<s>
It	O
also	O
provides	O
replacements	O
for	O
various	O
daemons	B-Operating_System
and	O
utilities	O
,	O
including	O
device	O
management	O
,	O
login	O
management	O
,	O
network	O
connection	O
management	O
,	O
and	O
event	O
logging	B-Application
.	O
</s>
<s>
The	O
name	O
systemd	B-Application
adheres	O
to	O
the	O
Unix	B-Application
convention	O
of	O
naming	O
daemons	B-Operating_System
by	O
appending	O
the	O
letter	O
d	O
.	O
It	O
also	O
plays	O
on	O
the	O
term	O
"	O
System	O
D	O
"	O
,	O
which	O
refers	O
to	O
a	O
person	O
's	O
ability	O
to	O
adapt	O
quickly	O
and	O
improvise	O
to	O
solve	O
problems	O
.	O
</s>
<s>
Since	O
2015	O
,	O
the	O
majority	O
of	O
Linux	B-Application
distributions	I-Application
have	O
adopted	O
systemd	B-Application
,	O
having	O
replaced	O
other	O
init	B-Operating_System
systems	O
such	O
as	O
SysV	O
init	B-Operating_System
.	O
</s>
<s>
It	O
has	O
been	O
praised	O
by	O
developers	O
and	O
users	O
of	O
distributions	O
that	O
adopted	O
it	O
for	O
providing	O
a	O
stable	O
,	O
fast	O
out-of-the-box	O
solution	O
for	O
issues	O
that	O
had	O
existed	O
in	O
the	O
Linux	B-Operating_System
space	O
for	O
years	O
.	O
</s>
<s>
At	O
the	O
time	O
of	O
adoption	O
of	O
systemd	B-Application
on	O
most	O
Linux	B-Application
distributions	I-Application
,	O
it	O
was	O
the	O
only	O
software	B-Application
suite	I-Application
that	O
offered	O
reliable	O
parallelism	B-Operating_System
during	O
boot	B-Operating_System
as	O
well	O
as	O
centralized	O
management	O
of	O
processes	B-Operating_System
,	O
daemons	B-Operating_System
,	O
services	O
and	O
mount	O
points	O
.	O
</s>
<s>
Critics	O
of	O
systemd	B-Application
contend	O
that	O
it	O
suffers	O
from	O
mission	O
creep	O
and	O
bloat	O
;	O
the	O
latter	O
affecting	O
other	O
software	O
(	O
such	O
as	O
the	O
GNOME	B-Application
desktop	I-Application
)	O
,	O
adding	O
dependencies	B-Application
on	O
systemd	B-Application
,	O
reducing	O
its	O
compatibility	O
with	O
other	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
and	O
making	O
it	O
difficult	O
for	O
sysadmins	B-Application
to	O
integrate	O
alternative	O
solutions	O
.	O
</s>
<s>
Concerns	O
have	O
also	O
been	O
raised	O
about	O
Red	O
Hat	O
and	O
its	O
parent	O
company	O
IBM	O
controlling	O
the	O
scene	O
of	O
init	B-Operating_System
systems	O
on	O
Linux	B-Operating_System
.	O
</s>
<s>
Critics	O
also	O
contend	O
that	O
the	O
complexity	O
of	O
systemd	B-Application
results	O
in	O
a	O
larger	O
attack	O
surface	O
,	O
reducing	O
the	O
overall	O
security	O
of	O
the	O
platform	O
.	O
</s>
<s>
Lennart	O
Poettering	O
and	O
Kay	O
Sievers	O
,	O
the	O
software	B-General_Concept
engineers	I-General_Concept
working	O
for	O
Red	O
Hat	O
who	O
initially	O
developed	O
systemd	B-Application
,	O
started	O
a	O
project	O
to	O
replace	O
Linux	B-Operating_System
's	O
conventional	O
System	O
V	O
init	B-Operating_System
in	O
2010	O
.	O
</s>
<s>
An	O
April	O
2010	O
blog	O
post	O
from	O
Poettering	O
,	O
titled	O
"	O
Rethinking	O
PID	B-Operating_System
1	O
"	O
,	O
introduced	O
an	O
experimental	O
version	O
of	O
what	O
would	O
later	O
become	O
systemd	B-Application
.	O
</s>
<s>
They	O
sought	O
to	O
surpass	O
the	O
efficiency	O
of	O
the	O
init	B-Operating_System
daemon	I-Operating_System
in	O
several	O
ways	O
.	O
</s>
<s>
They	O
wanted	O
to	O
improve	O
the	O
software	B-Architecture
framework	I-Architecture
for	O
expressing	O
dependencies	B-Application
,	O
to	O
allow	O
more	O
processing	O
to	O
be	O
done	O
concurrently	B-Operating_System
or	O
in	O
parallel	B-Operating_System
during	O
system	O
booting	B-Operating_System
,	O
and	O
to	O
reduce	O
the	O
computational	O
overhead	O
of	O
the	O
shell	B-Operating_System
.	O
</s>
<s>
In	O
May	O
2011	O
Fedora	O
Linux	B-Operating_System
became	O
the	O
first	O
major	O
Linux	B-Application
distribution	I-Application
to	O
enable	O
systemd	B-Application
by	O
default	O
,	O
replacing	O
Upstart	B-Device
.	O
</s>
<s>
The	O
reasoning	O
at	O
the	O
time	O
was	O
that	O
systemd	B-Application
provided	O
extensive	O
parallelization	B-Operating_System
during	O
startup	O
,	O
better	O
management	O
of	O
processes	B-Operating_System
and	O
overall	O
a	O
saner	O
,	O
dependency-based	O
approach	O
to	O
control	O
of	O
the	O
system	O
.	O
</s>
<s>
In	O
October	O
2012	O
,	O
Arch	O
Linux	B-Operating_System
made	O
systemd	B-Application
the	O
default	O
,	O
switching	O
from	O
SysVinit	O
.	O
</s>
<s>
Some	O
of	O
them	O
thought	O
that	O
the	O
criticism	O
towards	O
the	O
implementation	O
of	O
systemd	B-Application
was	O
not	O
based	O
on	O
actual	O
shortcomings	O
of	O
the	O
software	O
,	O
rather	O
the	O
disliking	O
of	O
Lennart	O
from	O
a	O
part	O
of	O
the	O
Linux	B-Operating_System
community	O
and	O
the	O
general	O
hesitation	O
for	O
change	O
.	O
</s>
<s>
Specifically	O
,	O
some	O
of	O
the	O
complaints	O
regarding	O
systemd	B-Application
not	O
being	O
programmed	O
in	O
bash	O
,	O
it	O
being	O
bigger	O
and	O
more	O
extensive	O
than	O
SysVinit	O
,	O
the	O
use	O
of	O
D-bus	B-Language
,	O
and	O
the	O
optional	O
on-disk	O
format	O
of	O
the	O
journal	O
were	O
regarded	O
as	O
advantages	O
by	O
programmers	O
.	O
</s>
<s>
Between	O
October	O
2013	O
and	O
February	O
2014	O
,	O
a	O
long	O
debate	O
among	O
the	O
Debian	O
Technical	O
Committee	O
occurred	O
on	O
the	O
Debian	O
mailing	O
list	O
,	O
discussing	O
which	O
init	B-Operating_System
system	O
to	O
use	O
as	O
the	O
default	O
in	O
Debian	O
8	O
"	O
jessie	O
"	O
,	O
and	O
culminating	O
in	O
a	O
decision	O
in	O
favor	O
of	O
systemd	B-Application
.	O
</s>
<s>
In	O
February	O
2014	O
,	O
after	O
Debian	O
's	O
decision	O
was	O
made	O
,	O
Mark	O
Shuttleworth	O
announced	O
on	O
his	O
blog	O
that	O
Ubuntu	B-Operating_System
would	O
follow	O
in	O
implementing	O
systemd	B-Application
,	O
discarding	O
its	O
own	O
Upstart	B-Device
.	O
</s>
<s>
In	O
November	O
2014	O
Debian	O
Developer	O
Joey	O
Hess	O
,	O
Debian	O
Technical	O
Committee	O
members	O
Russ	O
Allbery	O
and	O
Ian	O
Jackson	O
,	O
and	O
systemd	B-Application
package-maintainer	O
Tollef	O
Fog	O
Heen	O
resigned	O
from	O
their	O
positions	O
.	O
</s>
<s>
All	O
four	O
justified	O
their	O
decision	O
on	O
the	O
public	O
Debian	O
mailing	O
list	O
and	O
in	O
personal	O
blogs	O
with	O
their	O
exposure	O
to	O
extraordinary	O
stress-levels	O
related	O
to	O
ongoing	O
disputes	O
on	O
systemd	B-Application
integration	O
within	O
the	O
Debian	O
and	O
FOSS	B-License
community	O
that	O
rendered	O
regular	O
maintenance	O
virtually	O
impossible	O
.	O
</s>
<s>
In	O
August	O
2015	O
systemd	B-Application
started	O
providing	O
a	O
login	O
shell	B-Operating_System
,	O
callable	O
via	O
.	O
</s>
<s>
In	O
September	O
2016	O
,	O
a	O
security	O
bug	O
was	O
discovered	O
that	O
allowed	O
any	O
unprivileged	O
user	O
to	O
perform	O
a	O
denial-of-service	O
attack	O
against	O
systemd	B-Application
.	O
</s>
<s>
Rich	O
Felker	O
,	O
developer	O
of	O
musl	B-Language
,	O
stated	O
that	O
this	O
bug	O
reveals	O
a	O
major	O
"	O
system	O
development	O
design	O
flaw	O
"	O
.	O
</s>
<s>
In	O
2017	O
another	O
security	O
bug	O
was	O
discovered	O
in	O
systemd	B-Application
,	O
,	O
which	O
"	O
allows	O
disruption	O
of	O
service	O
"	O
by	O
a	O
"	O
malicious	O
DNS	O
server	O
"	O
.	O
</s>
<s>
Poettering	O
describes	O
systemd	B-Application
development	O
as	O
"	O
never	O
finished	O
,	O
never	O
complete	O
,	O
but	O
tracking	O
progress	O
of	O
technology	O
"	O
.	O
</s>
<s>
In	O
May	O
2014	O
,	O
Poettering	O
further	O
described	O
systemd	B-Application
as	O
unifying	O
"	O
pointless	O
differences	O
between	O
distributions	O
"	O
,	O
by	O
providing	O
the	O
following	O
three	O
general	O
functions	O
:	O
</s>
<s>
Systemd	B-Application
includes	O
features	O
like	O
on-demand	O
starting	O
of	O
daemons	B-Operating_System
,	O
snapshot	B-Application
support	O
,	O
process	O
tracking	O
and	O
Inhibitor	O
Locks	O
.	O
</s>
<s>
It	O
is	O
not	O
just	O
the	O
name	O
of	O
the	O
init	B-Operating_System
daemon	I-Operating_System
but	O
also	O
refers	O
to	O
the	O
entire	O
software	O
bundle	O
around	O
it	O
,	O
which	O
,	O
in	O
addition	O
to	O
the	O
init	B-Operating_System
daemon	I-Operating_System
,	O
includes	O
the	O
daemons	B-Operating_System
,	O
and	O
,	O
and	O
many	O
other	O
low-level	O
components	O
.	O
</s>
<s>
In	O
January	O
2013	O
,	O
Poettering	O
described	O
systemd	B-Application
not	O
as	O
one	O
program	O
,	O
but	O
rather	O
a	O
large	O
software	B-Application
suite	I-Application
that	O
includes	O
69	O
individual	O
binaries	O
.	O
</s>
<s>
As	O
an	O
integrated	O
software	B-Application
suite	I-Application
,	O
systemd	B-Application
replaces	O
the	O
startup	B-Application
sequences	I-Application
and	O
runlevels	B-Device
controlled	O
by	O
the	O
traditional	O
init	B-Operating_System
daemon	I-Operating_System
,	O
along	O
with	O
the	O
shell	B-Language
scripts	I-Language
executed	O
under	O
its	O
control	O
.	O
</s>
<s>
systemd	B-Application
also	O
integrates	O
many	O
other	O
services	O
that	O
are	O
common	O
on	O
Linux	B-Operating_System
systems	O
by	O
handling	O
user	O
logins	O
,	O
the	O
system	B-Device
console	I-Device
,	O
device	O
hotplugging	O
(	O
see	O
udev	B-Application
)	O
,	O
scheduled	O
execution	O
(	O
replacing	O
cron	B-General_Concept
)	O
,	O
logging	B-Application
,	O
hostnames	O
and	O
locales	O
.	O
</s>
<s>
Like	O
the	O
init	B-Operating_System
daemon	I-Operating_System
,	O
is	O
a	O
daemon	B-Operating_System
that	O
manages	O
other	O
daemons	B-Operating_System
,	O
which	O
,	O
including	O
itself	O
,	O
are	O
background	B-Operating_System
processes	I-Operating_System
.	O
</s>
<s>
is	O
the	O
first	O
daemon	B-Operating_System
to	O
start	O
during	O
booting	B-Operating_System
and	O
the	O
last	O
daemon	B-Operating_System
to	O
terminate	O
during	O
shutdown	B-Device
.	O
</s>
<s>
The	O
daemon	B-Operating_System
serves	O
as	O
the	O
root	O
of	O
the	O
user	B-Operating_System
space	I-Operating_System
's	O
process	B-Operating_System
tree	I-Operating_System
;	O
the	O
first	O
process	O
(	O
PID	B-Operating_System
1	O
)	O
has	O
a	O
special	O
role	O
on	O
Unix	B-Application
systems	I-Application
,	O
as	O
it	O
replaces	O
the	O
parent	O
of	O
a	O
process	O
when	O
the	O
original	O
parent	O
terminates	O
.	O
</s>
<s>
Therefore	O
,	O
the	O
first	O
process	O
is	O
particularly	O
well	O
suited	O
for	O
the	O
purpose	O
of	O
monitoring	O
daemons	B-Operating_System
.	O
</s>
<s>
executes	O
elements	O
of	O
its	O
startup	O
sequence	O
in	O
parallel	B-Operating_System
,	O
which	O
is	O
theoretically	O
faster	O
than	O
the	O
traditional	O
startup	O
sequence	O
approach	O
.	O
</s>
<s>
For	O
inter-process	B-Operating_System
communication	I-Operating_System
(	O
IPC	O
)	O
,	O
makes	O
Unix	B-Protocol
domain	I-Protocol
sockets	I-Protocol
and	O
D-Bus	B-Language
available	O
to	O
the	O
running	O
daemons	B-Operating_System
.	O
</s>
<s>
The	O
state	O
of	O
itself	O
can	O
also	O
be	O
preserved	O
in	O
a	O
snapshot	B-Application
for	O
future	O
recall	O
.	O
</s>
<s>
Following	O
its	O
integrated	O
approach	O
,	O
systemd	B-Application
also	O
provides	O
replacements	O
for	O
various	O
daemons	B-Operating_System
and	O
utilities	O
,	O
including	O
the	O
startup	O
shell	B-Language
scripts	I-Language
,	O
pm-utils	O
,	O
inetd	B-Protocol
,	O
,	O
syslog	B-Protocol
,	O
watchdog	O
,	O
cron	B-General_Concept
and	O
.	O
</s>
<s>
systemd	B-Application
's	O
core	O
components	O
include	O
the	O
following	O
:	O
</s>
<s>
is	O
a	O
system	O
and	O
service	B-Operating_System
manager	I-Operating_System
for	O
Linux	B-Application
operating	I-Application
systems	I-Application
.	O
</s>
<s>
is	O
a	O
command	O
to	O
introspect	O
and	O
control	O
the	O
state	O
of	O
the	O
systemd	B-Application
system	O
and	O
service	B-Operating_System
manager	I-Operating_System
.	O
</s>
<s>
Not	O
to	O
be	O
confused	O
with	O
sysctl	B-Application
.	O
</s>
<s>
may	O
be	O
used	O
to	O
determine	O
system	O
boot-up	O
performance	O
statistics	O
and	O
retrieve	O
other	O
state	O
and	O
tracing	O
information	O
from	O
the	O
system	O
and	O
service	B-Operating_System
manager	I-Operating_System
.	O
</s>
<s>
tracks	O
processes	B-Operating_System
using	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
's	O
cgroups	B-Application
subsystem	O
instead	O
of	O
using	O
process	B-Operating_System
identifiers	I-Operating_System
(	O
PIDs	O
)	O
;	O
thus	O
,	O
daemons	B-Operating_System
cannot	O
"	O
escape	O
"	O
,	O
not	O
even	O
by	O
double-forking	O
.	O
</s>
<s>
not	O
only	O
uses	O
cgroups	B-Application
,	O
but	O
also	O
augments	O
them	O
with	O
and	O
,	O
two	O
utility	O
programs	O
that	O
facilitate	O
the	O
creation	O
and	O
management	O
of	O
Linux	B-Operating_System
containers	O
.	O
</s>
<s>
Since	O
version	O
205	O
,	O
systemd	B-Application
also	O
offers	O
ControlGroupInterface	O
,	O
which	O
is	O
an	O
API	O
to	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
cgroups	B-Application
.	O
</s>
<s>
The	O
Linux	B-Operating_System
kernel	I-Operating_System
cgroups	B-Application
are	O
adapted	O
to	O
support	O
kernfs	B-Application
,	O
and	O
are	O
being	O
modified	O
to	O
support	O
a	O
unified	O
hierarchy	O
.	O
</s>
<s>
Beside	O
its	O
primary	O
purpose	O
of	O
providing	O
a	O
Linux	B-Operating_System
init	B-Operating_System
system	O
,	O
the	O
systemd	B-Application
suite	O
can	O
provide	O
additional	O
functionality	O
,	O
including	O
the	O
following	O
components	O
:	O
</s>
<s>
is	O
a	O
daemon	B-Operating_System
responsible	O
for	O
event	O
logging	B-Application
,	O
with	O
append-only	O
binary	O
files	O
serving	O
as	O
its	O
logfiles	B-Application
.	O
</s>
<s>
The	O
system	B-Application
administrator	I-Application
may	O
choose	O
whether	O
to	O
log	O
system	O
events	O
with	O
,	O
or	O
.	O
</s>
<s>
is	O
the	O
standard	O
library	O
for	O
utilizing	O
udev	B-Application
,	O
which	O
allows	O
third-party	O
applications	B-Application
to	O
query	O
udev	B-Application
resources	O
.	O
</s>
<s>
is	O
a	O
daemon	B-Operating_System
that	O
manages	O
user	O
logins	O
and	O
seats	O
in	O
various	O
ways	O
.	O
</s>
<s>
It	O
is	O
an	O
integrated	O
login	O
manager	O
that	O
offers	O
multiseat	B-Operating_System
improvements	O
and	O
replaces	O
ConsoleKit	O
,	O
which	O
is	O
no	O
longer	O
maintained	O
.	O
</s>
<s>
For	O
X11	B-Device
display	I-Device
managers	I-Device
the	O
switch	O
to	O
requires	O
a	O
minimal	O
amount	O
of	O
porting	O
.	O
</s>
<s>
It	O
was	O
integrated	O
in	O
systemd	B-Application
version	O
30	O
.	O
</s>
<s>
is	O
a	O
daemon	B-Operating_System
that	O
provides	O
portable	O
human-user	O
accounts	O
that	O
are	O
independent	O
of	O
current	O
system	O
configuration	O
.	O
</s>
<s>
manages	O
the	O
user	O
's	O
home	O
directory	O
in	O
various	O
ways	O
such	O
as	O
a	O
plain	O
directory	O
,	O
a	O
btrfs	B-Operating_System
subvolume	O
,	O
a	O
Linux	B-Operating_System
Unified	O
Key	O
Setup	O
volume	O
,	O
an	O
fscrypt	O
directory	O
,	O
or	O
mounted	O
from	O
an	O
SMB	B-Operating_System
server	O
.	O
</s>
<s>
is	O
a	O
daemon	B-Operating_System
to	O
handle	O
the	O
configuration	O
of	O
the	O
network	O
interfaces	O
;	O
in	O
version	O
209	O
,	O
when	O
it	O
was	O
first	O
integrated	O
,	O
support	O
was	O
limited	O
to	O
statically	O
assigned	O
addresses	O
and	O
basic	O
support	O
for	O
bridging	B-Protocol
configuration	O
.	O
</s>
<s>
In	O
July	O
2014	O
,	O
systemd	B-Application
version	O
215	O
was	O
released	O
,	O
adding	O
new	O
features	O
such	O
as	O
a	O
DHCP	B-Protocol
server	I-Protocol
for	O
IPv4	B-Protocol
hosts	O
,	O
and	O
VXLAN	B-Protocol
support	O
.	O
</s>
<s>
networkctl	O
may	O
be	O
used	O
to	O
review	O
the	O
state	O
of	O
the	O
network	O
links	O
as	O
seen	O
by	O
systemd-networkd	O
.	O
</s>
<s>
Configuration	O
of	O
new	O
interfaces	O
has	O
to	O
be	O
added	O
under	O
the	O
/lib/systemd/network/	O
as	O
a	O
new	O
file	O
ending	O
with	O
.network	O
extension	O
.	O
</s>
<s>
is	O
a	O
boot	B-Operating_System
manager	O
,	O
formerly	O
known	O
as	O
gummiboot	B-Application
.	O
</s>
<s>
Kay	O
Sievers	O
merged	B-General_Concept
it	O
into	O
systemd	B-Application
with	O
rev	O
220	O
.	O
</s>
<s>
is	O
a	O
daemon	B-Operating_System
that	O
can	O
be	O
used	O
to	O
control	O
time-related	O
settings	O
,	O
such	O
as	O
the	O
system	O
time	O
,	O
system	O
time	B-Device
zone	I-Device
,	O
or	O
selection	O
between	O
UTC	O
and	O
local	O
time-zone	O
system	O
clock	O
.	O
</s>
<s>
It	O
is	O
accessible	O
through	O
D-Bus	B-Language
.	O
</s>
<s>
It	O
was	O
integrated	O
in	O
systemd	B-Application
version	O
30	O
.	O
</s>
<s>
is	O
a	O
daemon	B-Operating_System
that	O
has	O
been	O
added	O
for	O
synchronizing	O
the	O
system	O
clock	O
across	O
the	O
network	O
.	O
</s>
<s>
udev	B-Application
is	O
a	O
device	O
manager	O
for	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
,	O
which	O
handles	O
the	O
directory	O
and	O
all	O
user	B-Operating_System
space	I-Operating_System
actions	O
when	O
adding/removing	O
devices	O
,	O
including	O
firmware	B-Application
loading	O
.	O
</s>
<s>
In	O
April	O
2012	O
,	O
the	O
source	O
tree	O
for	O
udev	B-Application
was	O
merged	B-General_Concept
into	O
the	O
systemd	B-Application
source	O
tree	O
.	O
</s>
<s>
In	O
order	O
to	O
match	O
the	O
version	O
number	O
of	O
udev	B-Application
,	O
Systemd	B-Application
maintainers	O
bumped	O
the	O
version	O
number	O
directly	O
from	O
44	O
to	O
183	O
.	O
</s>
<s>
On	O
29	O
May	O
2014	O
,	O
support	O
for	O
firmware	B-Application
loading	O
through	O
udev	B-Application
was	O
dropped	O
from	O
systemd	B-Application
,	O
as	O
it	O
was	O
decided	O
that	O
the	O
kernel	B-Operating_System
should	O
be	O
responsible	O
for	O
loading	O
firmware	B-Application
.	O
</s>
<s>
records	O
initialization	O
instructions	O
for	O
each	O
daemon	B-Operating_System
in	O
a	O
configuration	B-Protocol
file	I-Protocol
(	O
referred	O
to	O
as	O
a	O
"	O
unit	O
file	O
"	O
)	O
that	O
uses	O
a	O
declarative	B-Language
language	I-Language
,	O
replacing	O
the	O
traditionally	O
used	O
per-daemon	O
startup	O
shell	B-Language
scripts	I-Language
.	O
</s>
<s>
Linux	B-Application
distribution	I-Application
Date	O
added	O
to	O
software	B-Application
repository	I-Application
Enabled	O
by	O
default	O
?	O
</s>
<s>
Alpine	O
Linux	B-Operating_System
Android	B-Application
Arch	O
Linux	B-Operating_System
antiX	B-Application
Linux	I-Application
Artix	O
Linux	B-Operating_System
CentOS	O
(	O
v7.0	O
)	O
CoreOS	B-Application
(	O
v94.0.0	O
)	O
Debian	O
(	O
v8.0	O
)	O
.	O
</s>
<s>
While	O
many	O
distributions	O
boot	B-Operating_System
systemd	B-Application
by	O
default	O
,	O
some	O
allow	O
other	O
init	B-Operating_System
systems	O
to	O
be	O
used	O
;	O
in	O
this	O
case	O
switching	O
the	O
init	B-Operating_System
system	O
is	O
possible	O
by	O
installing	O
the	O
appropriate	O
packages	O
.	O
</s>
<s>
A	O
fork	B-Application
of	O
Debian	O
called	O
Devuan	O
was	O
developed	O
to	O
avoid	O
systemd	B-Application
and	O
has	O
reached	O
version	O
4.0	O
for	O
stable	O
usage	O
.	O
</s>
<s>
In	O
December	O
2019	O
,	O
the	O
Debian	O
project	O
voted	O
in	O
favour	O
of	O
retaining	O
systemd	B-Application
as	O
the	O
default	O
init	B-Operating_System
system	O
for	O
the	O
distribution	O
,	O
but	O
with	O
support	O
for	O
"	O
exploring	O
alternatives	O
"	O
.	O
</s>
<s>
In	O
the	O
interest	O
of	O
enhancing	O
the	O
interoperability	O
between	O
systemd	B-Application
and	O
the	O
GNOME	B-Application
desktop	I-Application
environment	I-Application
,	O
systemd	B-Application
coauthor	O
Lennart	O
Poettering	O
asked	O
the	O
GNOME	B-Application
Project	O
to	O
consider	O
making	O
systemd	B-Application
an	O
external	O
dependency	B-Application
of	O
GNOME	B-Application
3.2	O
.	O
</s>
<s>
In	O
November	O
2012	O
,	O
the	O
GNOME	B-Application
Project	O
concluded	O
that	O
basic	O
GNOME	B-Application
functionality	O
should	O
not	O
rely	O
on	O
systemd	B-Application
.	O
</s>
<s>
However	O
,	O
GNOME	B-Application
3.8	O
introduced	O
a	O
compile-time	O
choice	O
between	O
the	O
and	O
ConsoleKit	O
API	O
,	O
the	O
former	O
being	O
provided	O
at	O
the	O
time	O
only	O
by	O
systemd	B-Application
.	O
</s>
<s>
Ubuntu	B-Operating_System
provided	O
a	O
separate	O
binary	O
but	O
systemd	B-Application
became	O
a	O
de	O
facto	O
dependency	B-Application
of	O
GNOME	B-Application
for	O
most	O
Linux	B-Application
distributions	I-Application
,	O
in	O
particular	O
since	O
ConsoleKit	O
is	O
no	O
longer	O
actively	O
maintained	O
and	O
upstream	O
recommends	O
the	O
use	O
of	O
instead	O
.	O
</s>
<s>
The	O
developers	O
of	O
Gentoo	B-Application
Linux	I-Application
also	O
attempted	O
to	O
adapt	O
these	O
changes	O
in	O
OpenRC	B-Device
,	O
but	O
the	O
implementation	O
contained	O
too	O
many	O
bugs	O
,	O
causing	O
the	O
distribution	O
to	O
mark	O
systemd	B-Application
as	O
a	O
dependency	B-Application
of	O
GNOME	B-Application
.	O
</s>
<s>
GNOME	B-Application
has	O
further	O
integrated	O
.	O
</s>
<s>
As	O
of	O
Mutter	B-Language
version	O
3.13.2	O
,	O
is	O
a	O
dependency	B-Application
for	O
Wayland	O
sessions	O
.	O
</s>
<s>
The	O
design	O
of	O
systemd	B-Application
has	O
ignited	O
controversy	O
within	O
the	O
free-software	O
community	O
.	O
</s>
<s>
Critics	O
regard	O
systemd	B-Application
as	O
overly	O
complex	O
and	O
suffering	O
from	O
continued	O
feature	O
creep	O
,	O
arguing	O
that	O
its	O
architecture	O
violates	O
the	B-Operating_System
Unix	I-Operating_System
philosophy	I-Operating_System
.	O
</s>
<s>
There	O
is	O
also	O
concern	O
that	O
it	O
forms	O
a	O
system	O
of	O
interlocked	O
dependencies	B-Application
,	O
thereby	O
giving	O
distribution	O
maintainers	O
little	O
choice	O
but	O
to	O
adopt	O
systemd	B-Application
as	O
more	O
user-space	B-Operating_System
software	O
comes	O
to	O
depend	O
on	O
its	O
components	O
,	O
which	O
is	O
similar	O
to	O
the	O
problems	O
created	O
by	O
PulseAudio	B-Library
,	O
another	O
project	O
which	O
was	O
also	O
developed	O
by	O
Lennart	O
Poettering	O
.	O
</s>
<s>
In	O
a	O
2012	O
interview	O
,	O
Slackware	B-Application
's	O
lead	O
Patrick	O
Volkerding	O
expressed	O
reservations	O
about	O
the	O
systemd	B-Application
architecture	O
,	O
stating	O
his	O
belief	O
that	O
its	O
design	O
was	O
contrary	O
to	O
the	B-Operating_System
Unix	I-Operating_System
philosophy	I-Operating_System
of	O
interconnected	O
utilities	O
with	O
narrowly	O
defined	O
functionalities	O
.	O
</s>
<s>
,	O
Slackware	B-Application
does	O
not	O
support	O
or	O
use	O
systemd	B-Application
,	O
but	O
Volkerding	O
has	O
not	O
ruled	O
out	O
the	O
possibility	O
of	O
switching	O
to	O
it	O
.	O
</s>
<s>
In	O
January	O
2013	O
,	O
Lennart	O
Poettering	O
attempted	O
to	O
address	O
concerns	O
about	O
systemd	B-Application
in	O
a	O
blog	O
post	O
called	O
The	O
Biggest	O
Myths	O
.	O
</s>
<s>
In	O
February	O
2014	O
,	O
musl	B-Language
's	O
Rich	O
Felker	O
opined	O
that	O
PID	B-Operating_System
1	O
is	O
too	O
special	O
to	O
be	O
saddled	O
with	O
additional	O
responsibilities	O
.	O
</s>
<s>
PID	B-Operating_System
1	O
should	O
only	O
be	O
responsible	O
for	O
starting	O
the	O
rest	O
of	O
the	O
init	B-Operating_System
system	O
and	O
reaping	O
zombie	O
processes	B-Operating_System
.	O
</s>
<s>
The	O
additional	O
functionality	O
added	O
by	O
systemd	B-Application
can	O
be	O
provided	O
elsewhere	O
and	O
unnecessarily	O
increases	O
the	O
complexity	O
and	O
attack	O
surface	O
of	O
PID	B-Operating_System
1	O
.	O
</s>
<s>
In	O
March	O
2014	O
Eric	O
S	O
.	O
Raymond	O
opined	O
that	O
systemd	B-Application
's	O
design	O
goals	O
were	O
prone	O
to	O
mission	O
creep	O
and	O
software	O
bloat	O
.	O
</s>
<s>
In	O
April	O
2014	O
,	O
Linus	O
Torvalds	O
expressed	O
reservations	O
about	O
the	O
attitude	O
of	O
Kay	O
Sievers	O
,	O
a	O
key	O
systemd	B-Application
developer	O
,	O
toward	O
users	O
and	O
bug	O
reports	O
in	O
regard	O
to	O
modifications	O
to	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
submitted	O
by	O
Sievers	O
.	O
</s>
<s>
In	O
late	O
April	O
2014	O
a	O
campaign	O
to	O
boycott	O
systemd	B-Application
was	O
launched	O
,	O
with	O
a	O
website	O
listing	O
various	O
reasons	O
against	O
its	O
adoption	O
.	O
</s>
<s>
In	O
an	O
August	O
2014	O
article	O
published	O
in	O
InfoWorld	O
,	O
Paul	O
Venezia	O
wrote	O
about	O
the	O
systemd	B-Application
controversy	O
and	O
attributed	O
the	O
controversy	O
to	O
violation	O
of	O
the	B-Operating_System
Unix	I-Operating_System
philosophy	I-Operating_System
,	O
and	O
to	O
"	O
enormous	O
egos	O
who	O
firmly	O
believe	O
they	O
can	O
do	O
no	O
wrong	O
"	O
.	O
</s>
<s>
The	O
article	O
also	O
characterizes	O
the	O
architecture	O
of	O
systemd	B-Application
as	O
similar	O
to	O
that	O
of	O
svchost.exe	O
,	O
a	O
critical	O
system	O
component	O
in	O
Microsoft	B-Application
Windows	I-Application
with	O
a	O
broad	O
functional	O
scope	O
.	O
</s>
<s>
In	O
a	O
September	O
2014	O
ZDNet	O
interview	O
,	O
prominent	O
Linux	B-Operating_System
kernel	I-Operating_System
developer	O
Theodore	O
Ts'o	O
expressed	O
his	O
opinion	O
that	O
the	O
dispute	O
over	O
systemd	B-Application
's	O
centralized	O
design	O
philosophy	O
,	O
more	O
than	O
technical	O
concerns	O
,	O
indicates	O
a	O
dangerous	O
general	O
trend	O
toward	O
uniformizing	O
the	O
Linux	B-Operating_System
ecosystem	O
,	O
alienating	O
and	O
marginalizing	O
parts	O
of	O
the	O
open-source	O
community	O
,	O
and	O
leaving	O
little	O
room	O
for	O
alternative	O
projects	O
.	O
</s>
<s>
He	O
cited	O
similarities	O
with	O
the	O
attitude	O
he	O
found	O
in	O
the	O
GNOME	B-Application
project	O
toward	O
non-standard	O
configurations	O
.	O
</s>
<s>
On	O
social	O
media	O
,	O
Ts'o	O
also	O
later	O
compared	O
the	O
attitudes	O
of	O
Sievers	O
and	O
his	O
co-developer	O
,	O
Lennart	O
Poettering	O
,	O
to	O
that	O
of	O
GNOME	B-Application
's	O
developers	O
.	O
</s>
<s>
Forks	B-Application
of	O
systemd	B-Application
are	O
closely	O
tied	O
to	O
critiques	O
of	O
it	O
outlined	O
in	O
the	O
above	O
section	O
.	O
</s>
<s>
Forks	B-Application
generally	O
try	O
to	O
improve	O
on	O
at	O
least	O
one	O
of	O
portability	O
(	O
to	O
other	O
libcs	O
and	O
Unix-like	B-Operating_System
systems	I-Operating_System
)	O
,	O
modularity	O
,	O
or	O
size	O
.	O
</s>
<s>
A	O
few	O
forks	B-Application
have	O
collaborated	O
under	O
the	O
FreeInit	O
banner	O
.	O
</s>
<s>
In	O
2012	O
,	O
the	O
Gentoo	B-Application
Linux	I-Application
project	O
created	O
a	O
fork	B-Application
of	O
udev	B-Application
in	O
order	O
to	O
avoid	O
dependency	B-Application
on	O
the	O
systemd	B-Application
architecture	O
.	O
</s>
<s>
The	O
resulting	O
fork	B-Application
is	O
called	O
eudev	O
and	O
it	O
makes	O
udev	B-Application
functionality	O
available	O
without	O
systemd	B-Application
.	O
</s>
<s>
A	O
stated	O
goal	O
of	O
the	O
project	O
is	O
to	O
keep	O
eudev	O
independent	O
of	O
any	O
Linux	B-Application
distribution	I-Application
or	O
init	B-Operating_System
system	O
.	O
</s>
<s>
In	O
2021	O
,	O
Gentoo	B-Application
announced	O
that	O
support	O
of	O
eudev	O
would	O
cease	O
at	O
the	O
beginning	O
of	O
2022	O
.	O
</s>
<s>
Elogind	O
is	O
the	O
systemd	B-Application
project	O
's	O
"	O
logind	O
"	O
,	O
extracted	O
out	O
to	O
be	O
a	O
standalone	O
daemon	B-Operating_System
.	O
</s>
<s>
Elogind	O
exposes	O
this	O
information	O
via	O
the	O
standard	O
org.freedesktop.login1	O
D-Bus	B-Language
interface	O
,	O
as	O
well	O
as	O
through	O
the	O
file	O
system	O
using	O
systemd	B-Application
's	O
standard	O
layout	O
.	O
</s>
<s>
There	O
is	O
a	O
"	O
libelogind.pc	O
"	O
pkg-config	B-Application
file	O
as	O
well	O
.	O
</s>
<s>
ConsoleKit	O
was	O
forked	O
in	O
October	O
2014	O
by	O
Xfce	B-Language
developers	O
wanting	O
its	O
features	O
to	O
still	O
be	O
maintained	O
and	O
available	O
on	O
operating	O
systems	O
other	O
than	O
Linux	B-Operating_System
.	O
</s>
<s>
LoginKit	O
was	O
an	O
attempt	O
to	O
implement	O
a	O
logind	O
(	O
systemd-logind	O
)	O
shim	B-General_Concept
,	O
which	O
would	O
allow	O
packages	O
that	O
depend	O
on	O
systemd-logind	O
to	O
work	O
without	O
dependency	B-Application
on	O
a	O
specific	O
init	B-Operating_System
system	O
.	O
</s>
<s>
In	O
2014	O
,	O
a	O
Google	B-Application
Summer	I-Application
of	I-Application
Code	I-Application
project	O
named	O
"	O
systembsd	O
"	O
was	O
started	O
in	O
order	O
to	O
provide	O
alternative	O
implementations	O
of	O
these	O
APIs	O
for	O
OpenBSD	B-Operating_System
.	O
</s>
<s>
The	O
original	O
project	O
developer	O
began	O
it	O
in	O
order	O
to	O
ease	O
his	O
transition	O
from	O
Linux	B-Operating_System
to	O
OpenBSD	B-Operating_System
.	O
</s>
<s>
The	O
systembsd	O
project	O
did	O
not	O
provide	O
an	O
init	B-Operating_System
replacement	O
,	O
but	O
aimed	O
to	O
provide	O
OpenBSD	B-Operating_System
with	O
compatible	O
daemons	B-Operating_System
for	O
,	O
,	O
,	O
and	O
.	O
</s>
<s>
The	O
project	O
did	O
not	O
create	O
new	O
systemd-like	O
functionality	O
,	O
and	O
was	O
only	O
meant	O
to	O
act	O
as	O
a	O
wrapper	O
over	O
the	O
native	O
OpenBSD	B-Operating_System
system	O
.	O
</s>
<s>
The	O
developer	O
aimed	O
for	O
systembsd	O
to	O
be	O
installable	O
as	O
part	O
of	O
the	O
ports	B-Application
collection	I-Application
,	O
not	O
as	O
part	O
of	O
a	O
base	O
system	O
,	O
stating	O
that	O
"	O
systemd	B-Application
and	O
*	O
BSD	O
differ	O
fundamentally	O
in	O
terms	O
of	O
philosophy	O
and	O
development	O
practices.	O
"	O
</s>
<s>
Notsystemd	O
intends	O
to	O
implement	O
all	O
systemd	B-Application
's	O
features	O
working	O
on	O
any	O
init	B-Operating_System
system	O
.	O
</s>
<s>
It	O
was	O
forked	O
by	O
the	O
Parabola	O
GNU/Linux	B-Application
-libre	O
developers	O
to	O
build	O
packages	O
with	O
their	O
development	O
tools	O
without	O
the	O
necessity	O
of	O
having	O
systemd	B-Application
installed	O
to	O
run	O
systemd-nspawn	O
.	O
</s>
<s>
In	O
2014	O
,	O
uselessd	O
was	O
created	O
as	O
a	O
lightweight	O
fork	B-Application
of	O
systemd	B-Application
.	O
</s>
<s>
The	O
project	O
sought	O
to	O
remove	O
features	O
and	O
programs	O
deemed	O
unnecessary	O
for	O
an	O
init	B-Operating_System
system	O
,	O
as	O
well	O
as	O
address	O
other	O
perceived	O
faults	O
.	O
</s>
<s>
uselessd	O
supported	O
the	O
musl	B-Language
and	O
µClibc	B-Language
libraries	O
,	O
so	O
it	O
may	O
have	O
been	O
used	O
on	O
embedded	B-Architecture
systems	I-Architecture
,	O
whereas	O
systemd	B-Application
only	O
supports	O
glibc	B-Language
.	O
</s>
<s>
The	O
uselessd	O
project	O
had	O
planned	O
further	O
improvements	O
on	O
cross-platform	O
compatibility	O
,	O
as	O
well	O
as	O
architectural	O
overhauls	O
and	O
refactoring	O
for	O
the	O
Linux	B-Operating_System
build	O
in	O
the	O
future	O
.	O
</s>
<s>
InitWare	O
is	O
a	O
modular	O
refactor	O
of	O
systemd	B-Application
,	O
porting	O
the	O
system	O
to	O
BSD	O
platforms	B-Device
without	O
glibc	B-Language
or	O
Linux-specific	O
system	O
calls	O
.	O
</s>
<s>
It	O
is	O
known	O
to	O
work	O
on	O
DragonFly	O
BSD	O
,	O
FreeBSD	O
,	O
NetBSD	O
,	O
and	O
GNU/Linux	B-Application
.	O
</s>
