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         libattr (optional)
 119         libselinux (optional)
 120         liblzma (optional)
 121         libgcrypt (optional)
 122         libqrencode (optional)
 123         libmicrohttpd (optional)
 124         libpython (optional)
 125         make, gcc, and similar tools
 126
 127         During runtime, you need the following additional
 128         dependencies:
 129
 130         util-linux >= v2.19 (requires fsck -l, agetty -s),
 131                       v2.21 required for tests in test/
 132         dbus >= 1.4.0 (strictly speaking optional, but recommended)
 133         sulogin (from util-linux >= 2.22 or sysvinit-tools, optional but recommended,
 134                  required for tests in test/)
 135         dracut (optional)
 136         PolicyKit (optional)
 137
 138         When building from git, you need the following additional
 139         dependencies:
 140
 141         docbook-xsl
 142         xsltproc
 143         automake
 144         autoconf
 145         libtool
 146         intltool
 147         gperf
 148         gtkdocize (optional)
 149         python (optional)
 150         python-lxml (optional, but required to build the indices)
 151         sphinx (optional)
 152
 153         When systemd-hostnamed is used, it is strongly recommended to
 154         install nss-myhostname to ensure that, in a world of
 155         dynamically changing hostnames, the hostname stays resolvable
 156         under all circumstances. In fact, systemd-hostnamed will warn
 157         if nss-myhostname is not installed.
 158
 159         To build HTML documentation for python-systemd using sphinx,
 160         please first install systemd (using 'make install'), and then
 161         invoke sphinx-build with 'make sphinx-<target>', with <target>
 162         being 'html' or 'latexpdf'. If using DESTDIR for installation,
 163         pass the same DESTDIR to 'make sphinx-html' invocation.
 164
 165 USERS AND GROUPS:
 166         Default udev rules use the following standard system group
 167         names, which need to be resolvable by getgrnam() at any time,
 168         even in the very early boot stages, where no other databases
 169         and network are available:
 170
 171         audio, cdrom, dialout, disk, input, kmem, lp, tape, tty, video
 172
 173         During runtime, the journal daemon requires the
 174         "systemd-journal" system group to exist. New journal files will
 175         be readable by this group (but not writable), which may be used
 176         to grant specific users read access.
 177
 178         It is also recommended to grant read access to all journal
 179         files to the system groups "wheel" and "adm" with a command
 180         like the following in the post installation script of the
 181         package:
 182
 183         # setfacl -nm g:wheel:rx,d:g:wheel:rx,g:adm:rx,d:g:adm:rx /var/log/journal/
 184
 185         The journal gateway daemon requires the
 186         "systemd-journal-gateway" system user and group to
 187         exist. During execution this network facing service will drop
 188         privileges and assume this uid/gid for security reasons.
 189
 190         Similar, the NTP daemon requires the "systemd-timesync" system
 191         user and group to exist.
 192
 193         Similar, the network management daemon requires the
 194         "systemd-network" system user and group to exist.
 195
 196         Similar, the name resolution daemon requires the
 197         "systemd-resolve" system user and group to exist.
 198
 199         Similar, the kdbus dbus1 proxy daemon requires the
 200         "systemd-bus-proxy" system user and group to exist.
 201
 202 WARNINGS:
 203         systemd will warn you during boot if /etc/mtab is not a
 204         symlink to /proc/mounts. Please ensure that /etc/mtab is a
 205         proper symlink.
 206
 207         systemd will warn you during boot if /usr is on a different
 208         file system than /. While in systemd itself very little will
 209         break if /usr is on a separate partition, many of its
 210         dependencies very likely will break sooner or later in one
 211         form or another. For example, udev rules tend to refer to
 212         binaries in /usr, binaries that link to libraries in /usr or
 213         binaries that refer to data files in /usr. Since these
 214         breakages are not always directly visible, systemd will warn
 215         about this, since this kind of file system setup is not really
 216         supported anymore by the basic set of Linux OS components.
 217
 218         systemd requires that the /run mount point exists. systemd also
 219         requires that /var/run is a a symlink to /run.
 220
 221         For more information on this issue consult
 222         http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
 223
 224         To run systemd under valgrind, compile with VALGRIND defined
 225         (e.g. ./configure CPPFLAGS='... -DVALGRIND=1'). Otherwise,
 226         false positives will be triggered by code which violates
 227         some rules but is actually safe.