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           CONFIG_DEVTMPFS
  42           CONFIG_CGROUPS (it's OK to disable all controllers)
  43           CONFIG_INOTIFY_USER
  44           CONFIG_SIGNALFD
  45           CONFIG_TIMERFD
  46           CONFIG_EPOLL
  47           CONFIG_NET
  48           CONFIG_SYSFS
  49           CONFIG_PROC_FS
  50           CONFIG_FHANDLE (libudev, mount and bind mount handling)
  51
  52         Linux kernel >= 3.8 for Smack support
  53
  54         Udev will fail to work with the legacy layout:
  55           CONFIG_SYSFS_DEPRECATED=n
  56
  57         Legacy hotplug slows down the system and confuses udev:
  58           CONFIG_UEVENT_HELPER_PATH=""
  59
  60         Userspace firmware loading is deprecated, will go away, and
  61         sometimes causes problems:
  62           CONFIG_FW_LOADER_USER_HELPER=n
  63
  64         Some udev rules and virtualization detection relies on it:
  65           CONFIG_DMIID
  66
  67         Support for some SCSI devices serial number retrieval, to
  68         create additional symlinks in /dev/disk/ and /dev/tape:
  69           CONFIG_BLK_DEV_BSG
  70
  71         Optional but strongly recommended:
  72           CONFIG_IPV6
  73           CONFIG_AUTOFS4_FS
  74           CONFIG_TMPFS_POSIX_ACL
  75           CONFIG_TMPFS_XATTR
  76           CONFIG_SECCOMP
  77
  78         For systemd-bootchart, several proc debug interfaces are required:
  79           CONFIG_SCHEDSTATS
  80           CONFIG_SCHED_DEBUG
  81
  82         For UEFI systems:
  83           CONFIG_EFI_VARS
  84           CONFIG_EFI_PARTITION
  85
  86         Note that kernel auditing is broken when used with systemd's
  87         container code. When using systemd in conjunction with
  88         containers, please make sure to either turn off auditing at
  89         runtime using the kernel command line option "audit=0", or
  90         turn it off at kernel compile time using:
  91           CONFIG_AUDIT=n
  92         If systemd is compiled with libseccomp support on
  93         architectures which do not use socketcall() and where seccomp
  94         is supported (this effectively means x86-64 and ARM, but
  95         excludes 32bit x86!), then nspawn will now install a
  96         work-around seccomp filter that makes containers boot even
  97         with audit being enabled. This works correctly only on kernels
  98         3.14 and newer though. TL;DR: turn audit off, still.
  99
 100         glibc >= 2.14
 101         libcap
 102         libseccomp >= 1.0.0 (optional)
 103         libblkid >= 2.20 (from util-linux) (optional)
 104         libkmod >= 15 (optional)
 105         PAM >= 1.1.2 (optional)
 106         libcryptsetup (optional)
 107         libaudit (optional)
 108         libacl (optional)
 109         libattr (optional)
 110         libselinux (optional)
 111         liblzma (optional)
 112         tcpwrappers (optional)
 113         libgcrypt (optional)
 114         libqrencode (optional)
 115         libmicrohttpd (optional)
 116         libpython (optional)
 117         make, gcc, and similar tools
 118
 119         To sucessfully use --compat-libs, gcc >= 4.8 seems necessary.
 120
 121         During runtime, you need the following additional
 122         dependencies:
 123
 124         util-linux >= v2.19 (requires fsck -l, agetty -s),
 125                       v2.21 required for tests in test/
 126         dbus >= 1.4.0 (strictly speaking optional, but recommended)
 127         sulogin (from util-linux >= 2.22 or sysvinit-tools, optional but recommended,
 128                  required for tests in test/)
 129         dracut (optional)
 130         PolicyKit (optional)
 131
 132         When building from git, you need the following additional
 133         dependencies:
 134
 135         docbook-xsl
 136         xsltproc
 137         automake
 138         autoconf
 139         libtool
 140         intltool
 141         gperf
 142         gtkdocize (optional)
 143         python (optional)
 144         python-lxml (optional, but required to build the indices)
 145         sphinx (optional)
 146
 147         When systemd-hostnamed is used, it is strongly recommended to
 148         install nss-myhostname to ensure that, in a world of
 149         dynamically changing hostnames, the hostname stays resolvable
 150         under all circumstances. In fact, systemd-hostnamed will warn
 151         if nss-myhostname is not installed.
 152
 153         To build HTML documentation for python-systemd using sphinx,
 154         please first install systemd (using 'make install'), and then
 155         invoke sphinx-build with 'make sphinx-<target>', with <target>
 156         being 'html' or 'latexpdf'. If using DESTDIR for installation,
 157         pass the same DESTDIR to 'make sphinx-html' invocation.
 158
 159 USERS AND GROUPS:
 160         Default udev rules use the following standard system group
 161         names, which need to be resolvable by getgrnam() at any time,
 162         even in the very early boot stages, where no other databases
 163         and network are available:
 164
 165         tty, dialout, kmem, video, audio, lp, floppy, cdrom, tape, disk
 166
 167         During runtime, the journal daemon requires the
 168         "systemd-journal" system group to exist. New journal files will
 169         be readable by this group (but not writable), which may be used
 170         to grant specific users read access.
 171
 172         It is also recommended to grant read access to all journal
 173         files to the system groups "wheel" and "adm" with a command
 174         like the following in the post installation script of the
 175         package:
 176
 177         # setfacl -nm g:wheel:rx,d:g:wheel:rx,g:adm:rx,d:g:adm:rx /var/log/journal/
 178
 179         The journal gateway daemon requires the
 180         "systemd-journal-gateway" system user and group to
 181         exist. During execution this network facing service will drop
 182         privileges and assume this uid/gid for security reasons.
 183
 184 WARNINGS:
 185         systemd will warn you during boot if /etc/mtab is not a
 186         symlink to /proc/mounts. Please ensure that /etc/mtab is a
 187         proper symlink.
 188
 189         systemd will warn you during boot if /usr is on a different
 190         file system than /. While in systemd itself very little will
 191         break if /usr is on a separate partition, many of its
 192         dependencies very likely will break sooner or later in one
 193         form or another. For example, udev rules tend to refer to
 194         binaries in /usr, binaries that link to libraries in /usr or
 195         binaries that refer to data files in /usr. Since these
 196         breakages are not always directly visible, systemd will warn
 197         about this, since this kind of file system setup is not really
 198         supported anymore by the basic set of Linux OS components.
 199
 200         systemd requires that the /run mount point exists. systemd also
 201         requires that /var/run is a a symlink → /run.
 202
 203         For more information on this issue consult
 204         http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
 205
 206         To run systemd under valgrind, compile with VALGRIND defined
 207         (e.g. ./configure CPPFLAGS='... -DVALGRIND=1'). Otherwise,
 208         false positives will be triggered by code which violates
 209         some rules but is actually safe.