README

   1 systemd System and Service Manager
   2
   3 DETAILS:
   4         http://0pointer.de/blog/projects/systemd.html
   5
   6 WEB SITE:
   7         http://www.freedesktop.org/wiki/Software/systemd
   8
   9 GIT:
  10         git://anongit.freedesktop.org/systemd/systemd
  11         ssh://git.freedesktop.org/git/systemd/systemd
  12
  13 GITWEB:
  14         http://cgit.freedesktop.org/systemd/systemd
  15
  16 MAILING LIST:
  17         http://lists.freedesktop.org/mailman/listinfo/systemd-devel
  18         http://lists.freedesktop.org/mailman/listinfo/systemd-commits
  19
  20 IRC:
  21         #systemd on irc.freenode.org
  22
  23 BUG REPORTS:
  24         https://bugs.freedesktop.org/enter_bug.cgi?product=systemd
  25
  26 AUTHOR:
  27         Lennart Poettering
  28         Kay Sievers
  29         ...and many others
  30
  31 LICENSE:
  32         LGPLv2.1+ for all code
  33         - except sd-readahead.[ch] which is MIT
  34         - except src/shared/MurmurHash2.c which is Public Domain
  35         - except src/shared/siphash24.c which is CC0 Public Domain
  36         - except src/journal/lookup3.c which is Public Domain
  37         - except src/udev/* which is (currently still) GPLv2, GPLv2+
  38
  39 REQUIREMENTS:
  40         Linux kernel >= 3.0
  41         Linux kernel >= 3.3 for loop device partition support features with nspawn
  42         Linux kernel >= 3.8 for Smack support
  43
  44         Kernel Config Options:
  45           CONFIG_DEVTMPFS
  46           CONFIG_CGROUPS (it is OK to disable all controllers)
  47           CONFIG_INOTIFY_USER
  48           CONFIG_SIGNALFD
  49           CONFIG_TIMERFD
  50           CONFIG_EPOLL
  51           CONFIG_NET
  52           CONFIG_SYSFS
  53           CONFIG_PROC_FS
  54           CONFIG_FHANDLE (libudev, mount and bind mount handling)
  55
  56         Udev will fail to work with the legacy layout:
  57           CONFIG_SYSFS_DEPRECATED=n
  58
  59         Legacy hotplug slows down the system and confuses udev:
  60           CONFIG_UEVENT_HELPER_PATH=""
  61
  62         Userspace firmware loading is deprecated, will go away, and
  63         sometimes causes problems:
  64           CONFIG_FW_LOADER_USER_HELPER=n
  65
  66         Some udev rules and virtualization detection relies on it:
  67           CONFIG_DMIID
  68
  69         Support for some SCSI devices serial number retrieval, to
  70         create additional symlinks in /dev/disk/ and /dev/tape:
  71           CONFIG_BLK_DEV_BSG
  72
  73         Required for PrivateNetwork in service units:
  74           CONFIG_NET_NS
  75
  76         Optional but strongly recommended:
  77           CONFIG_IPV6
  78           CONFIG_AUTOFS4_FS
  79           CONFIG_TMPFS_POSIX_ACL
  80           CONFIG_TMPFS_XATTR
  81           CONFIG_SECCOMP
  82
  83         Required for CPUShares in resource control unit settings
  84           CONFIG_CGROUP_SCHED
  85           CONFIG_FAIR_GROUP_SCHED
  86
  87         For systemd-bootchart, several proc debug interfaces are required:
  88           CONFIG_SCHEDSTATS
  89           CONFIG_SCHED_DEBUG
  90
  91         For UEFI systems:
  92           CONFIG_EFIVAR_FS
  93           CONFIG_EFI_PARTITION
  94
  95         Note that kernel auditing is broken when used with systemd's
  96         container code. When using systemd in conjunction with
  97         containers, please make sure to either turn off auditing at
  98         runtime using the kernel command line option "audit=0", or
  99         turn it off at kernel compile time using:
 100           CONFIG_AUDIT=n
 101         If systemd is compiled with libseccomp support on
 102         architectures which do not use socketcall() and where seccomp
 103         is supported (this effectively means x86-64 and ARM, but
 104         excludes 32-bit x86!), then nspawn will now install a
 105         work-around seccomp filter that makes containers boot even
 106         with audit being enabled. This works correctly only on kernels
 107         3.14 and newer though. TL;DR: turn audit off, still.
 108
 109         glibc >= 2.14
 110         libcap
 111         libseccomp >= 1.0.0 (optional)
 112         libblkid >= 2.20 (from util-linux) (optional)
 113         libkmod >= 15 (optional)
 114         PAM >= 1.1.2 (optional)
 115         libcryptsetup (optional)
 116         libaudit (optional)
 117         libacl (optional)
 118         libselinux (optional)
 119         liblzma (optional)
 120         liblz4 >= 119 (optional)
 121         libgcrypt (optional)
 122         libqrencode (optional)
 123         libmicrohttpd (optional)
 124         libpython (optional)
 125         gobject-introspection > 1.40.0 (optional)
 126         elfutils >= 158 (optional)
 127         make, gcc, and similar tools
 128
 129         During runtime, you need the following additional
 130         dependencies:
 131
 132         util-linux >= v2.19 (requires fsck -l, agetty -s),
 133                       v2.21 required for tests in test/
 134         dbus >= 1.4.0 (strictly speaking optional, but recommended)
 135         sulogin (from util-linux >= 2.22 or sysvinit-tools, optional but recommended,
 136                  required for tests in test/)
 137         dracut (optional)
 138         PolicyKit (optional)
 139
 140         When building from git, you need the following additional
 141         dependencies:
 142
 143         docbook-xsl
 144         xsltproc
 145         automake
 146         autoconf
 147         libtool
 148         intltool
 149         gperf
 150         gtkdocize (optional)
 151         python (optional)
 152         python-lxml (optional, but required to build the indices)
 153         sphinx (optional)
 154
 155         When systemd-hostnamed is used, it is strongly recommended to
 156         install nss-myhostname to ensure that, in a world of
 157         dynamically changing hostnames, the hostname stays resolvable
 158         under all circumstances. In fact, systemd-hostnamed will warn
 159         if nss-myhostname is not installed.
 160
 161         To build HTML documentation for python-systemd using sphinx,
 162         please first install systemd (using 'make install'), and then
 163         invoke sphinx-build with 'make sphinx-<target>', with <target>
 164         being 'html' or 'latexpdf'. If using DESTDIR for installation,
 165         pass the same DESTDIR to 'make sphinx-html' invocation.
 166
 167 USERS AND GROUPS:
 168         Default udev rules use the following standard system group
 169         names, which need to be resolvable by getgrnam() at any time,
 170         even in the very early boot stages, where no other databases
 171         and network are available:
 172
 173         audio, cdrom, dialout, disk, input, kmem, lp, tape, tty, video
 174
 175         During runtime, the journal daemon requires the
 176         "systemd-journal" system group to exist. New journal files will
 177         be readable by this group (but not writable), which may be used
 178         to grant specific users read access.
 179
 180         It is also recommended to grant read access to all journal
 181         files to the system groups "wheel" and "adm" with a command
 182         like the following in the post installation script of the
 183         package:
 184
 185         # setfacl -nm g:wheel:rx,d:g:wheel:rx,g:adm:rx,d:g:adm:rx /var/log/journal/
 186
 187         The journal gateway daemon requires the
 188         "systemd-journal-gateway" system user and group to
 189         exist. During execution this network facing service will drop
 190         privileges and assume this uid/gid for security reasons.
 191
 192         Similarly, the NTP daemon requires the "systemd-timesync" system
 193         user and group to exist.
 194
 195         Similarly, the network management daemon requires the
 196         "systemd-network" system user and group to exist.
 197
 198         Similarly, the name resolution daemon requires the
 199         "systemd-resolve" system user and group to exist.
 200
 201         Similarly, the kdbus dbus1 proxy daemon requires the
 202         "systemd-bus-proxy" system user and group to exist.
 203
 204 WARNINGS:
 205         systemd will warn you during boot if /etc/mtab is not a
 206         symlink to /proc/mounts. Please ensure that /etc/mtab is a
 207         proper symlink.
 208
 209         systemd will warn you during boot if /usr is on a different
 210         file system than /. While in systemd itself very little will
 211         break if /usr is on a separate partition, many of its
 212         dependencies very likely will break sooner or later in one
 213         form or another. For example, udev rules tend to refer to
 214         binaries in /usr, binaries that link to libraries in /usr or
 215         binaries that refer to data files in /usr. Since these
 216         breakages are not always directly visible, systemd will warn
 217         about this, since this kind of file system setup is not really
 218         supported anymore by the basic set of Linux OS components.
 219
 220         systemd requires that the /run mount point exists. systemd also
 221         requires that /var/run is a a symlink to /run.
 222
 223         For more information on this issue consult
 224         http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
 225
 226         To run systemd under valgrind, compile with VALGRIND defined
 227         (e.g. ./configure CPPFLAGS='... -DVALGRIND=1'). Otherwise,
 228         false positives will be triggered by code which violates
 229         some rules but is actually safe.