1 systemd System and Service Manager
4 http://0pointer.de/blog/projects/systemd.html
7 http://www.freedesktop.org/wiki/Software/systemd
10 git@github.com:systemd/systemd.git
11 https://github.com/systemd/systemd.git
14 https://github.com/systemd/systemd
17 http://lists.freedesktop.org/mailman/listinfo/systemd-devel
18 http://lists.freedesktop.org/mailman/listinfo/systemd-commits
21 #systemd on irc.freenode.org
24 https://github.com/systemd/systemd/issues
32 LGPLv2.1+ for all code
33 - except src/basic/MurmurHash2.c which is Public Domain
34 - except src/basic/siphash24.c which is CC0 Public Domain
35 - except src/journal/lookup3.c which is Public Domain
36 - except src/udev/* which is (currently still) GPLv2, GPLv2+
40 Linux kernel >= 3.8 for Smack support
42 Kernel Config Options:
44 CONFIG_CGROUPS (it is OK to disable all controllers)
52 CONFIG_FHANDLE (libudev, mount and bind mount handling)
54 udev will fail to work with the legacy sysfs layout:
55 CONFIG_SYSFS_DEPRECATED=n
57 Legacy hotplug slows down the system and confuses udev:
58 CONFIG_UEVENT_HELPER_PATH=""
60 Userspace firmware loading is not supported and should
61 be disabled in the kernel:
62 CONFIG_FW_LOADER_USER_HELPER=n
64 Some udev rules and virtualization detection relies on it:
67 Support for some SCSI devices serial number retrieval, to
68 create additional symlinks in /dev/disk/ and /dev/tape:
71 Required for PrivateNetwork and PrivateDevices in service units:
73 CONFIG_DEVPTS_MULTIPLE_INSTANCES
74 Note that systemd-localed.service and other systemd units use
75 PrivateNetwork and PrivateDevices so this is effectively required.
77 Optional but strongly recommended:
81 CONFIG_{TMPFS,EXT4,XFS,BTRFS_FS,...}_POSIX_ACL
83 CONFIG_CHECKPOINT_RESTORE (for the kcmp() syscall)
85 Required for CPUShares in resource control unit settings
87 CONFIG_FAIR_GROUP_SCHED
89 Required for CPUQuota in resource control unit settings
92 For systemd-bootchart, several proc debug interfaces are required:
100 Note that kernel auditing is broken when used with systemd's
101 container code. When using systemd in conjunction with
102 containers, please make sure to either turn off auditing at
103 runtime using the kernel command line option "audit=0", or
104 turn it off at kernel compile time using:
106 If systemd is compiled with libseccomp support on
107 architectures which do not use socketcall() and where seccomp
108 is supported (this effectively means x86-64 and ARM, but
109 excludes 32-bit x86!), then nspawn will now install a
110 work-around seccomp filter that makes containers boot even
111 with audit being enabled. This works correctly only on kernels
112 3.14 and newer though. TL;DR: turn audit off, still.
116 libmount >= 2.20 (from util-linux)
117 libseccomp >= 1.0.0 (optional)
118 libblkid >= 2.24 (from util-linux) (optional)
119 libkmod >= 15 (optional)
120 PAM >= 1.1.2 (optional)
121 libcryptsetup (optional)
124 libselinux (optional)
126 liblz4 >= 119 (optional)
128 libqrencode (optional)
129 libmicrohttpd (optional)
132 elfutils >= 158 (optional)
133 make, gcc, and similar tools
135 During runtime, you need the following additional
138 util-linux >= v2.26 required
139 dbus >= 1.4.0 (strictly speaking optional, but recommended)
143 When building from git, the following tools are needed:
154 python-lxml (optional, but required to build the indices)
157 The build system is initialized with ./autogen.sh. A tar ball
159 git archive --format=tar --prefix=systemd-222/ v222 | xz > systemd-222.tar.xz
161 When systemd-hostnamed is used, it is strongly recommended to
162 install nss-myhostname to ensure that, in a world of
163 dynamically changing hostnames, the hostname stays resolvable
164 under all circumstances. In fact, systemd-hostnamed will warn
165 if nss-myhostname is not installed.
167 To build HTML documentation for python-systemd using sphinx,
168 please first install systemd (using 'make install'), and then
169 invoke sphinx-build with 'make sphinx-<target>', with <target>
170 being 'html' or 'latexpdf'. If using DESTDIR for installation,
171 pass the same DESTDIR to 'make sphinx-html' invocation.
174 Default udev rules use the following standard system group
175 names, which need to be resolvable by getgrnam() at any time,
176 even in the very early boot stages, where no other databases
177 and network are available:
179 audio, cdrom, dialout, disk, input, kmem, lp, tape, tty, video
181 During runtime, the journal daemon requires the
182 "systemd-journal" system group to exist. New journal files will
183 be readable by this group (but not writable), which may be used
184 to grant specific users read access. In addition, system
185 groups "wheel" and "adm" will be given read-only access to
186 journal files using systemd-tmpfiles.service.
188 The journal gateway daemon requires the
189 "systemd-journal-gateway" system user and group to
190 exist. During execution this network facing service will drop
191 privileges and assume this uid/gid for security reasons.
193 Similarly, the NTP daemon requires the "systemd-timesync" system
194 user and group to exist.
196 Similarly, the network management daemon requires the
197 "systemd-network" system user and group to exist.
199 Similarly, the name resolution daemon requires the
200 "systemd-resolve" system user and group to exist.
202 Similarly, the kdbus dbus1 proxy daemon requires the
203 "systemd-bus-proxy" system user and group to exist.
206 systemd ships with three NSS modules:
208 nss-myhostname resolves the local hostname to locally
209 configured IP addresses, as well as "localhost" to
212 nss-resolve enables DNS resolution via the systemd-resolved
213 DNS/LLMNR caching stub resolver "systemd-resolved".
215 nss-mymachines enables resolution of all local containers
216 registered with machined to their respective IP addresses.
218 To make use of these NSS modules, please add them to the
219 "hosts: " line in /etc/nsswitch.conf. The "resolve" module
220 should replace the glibc "dns" module in this file.
222 The three modules should be used in the following order:
224 hosts: files mymachines resolve myhostname
227 When calling "systemctl enable/disable/is-enabled" on a unit which is a
228 SysV init.d script, it calls /usr/lib/systemd/systemd-sysv-install;
229 this needs to translate the action into the distribution specific
230 mechanism such as chkconfig or update-rc.d. Packagers need to provide
231 this script if you need this functionality (you don't if you disabled
234 Please see src/systemctl/systemd-sysv-install.SKELETON for how this
235 needs to look like, and provide an implementation at the marked places.
238 systemd will warn you during boot if /etc/mtab is not a
239 symlink to /proc/mounts. Please ensure that /etc/mtab is a
242 systemd will warn you during boot if /usr is on a different
243 file system than /. While in systemd itself very little will
244 break if /usr is on a separate partition, many of its
245 dependencies very likely will break sooner or later in one
246 form or another. For example, udev rules tend to refer to
247 binaries in /usr, binaries that link to libraries in /usr or
248 binaries that refer to data files in /usr. Since these
249 breakages are not always directly visible, systemd will warn
250 about this, since this kind of file system setup is not really
251 supported anymore by the basic set of Linux OS components.
253 systemd requires that the /run mount point exists. systemd also
254 requires that /var/run is a symlink to /run.
256 For more information on this issue consult
257 http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
259 To run systemd under valgrind, compile with VALGRIND defined
260 (e.g. ./configure CPPFLAGS='... -DVALGRIND=1'). Otherwise,
261 false positives will be triggered by code which violates
262 some rules but is actually safe.
264 ENGINEERING AND CONSULTING SERVICES:
265 ENDOCODE <https://endocode.com/> offers professional
266 engineering and consulting services for systemd. Please
267 contact Chris Kühl <chris@endocode.com> for more information.