X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=README;h=5222637c2c77c210010e36df42fdd701e1a10fa7;hp=a5d569028dfb8750bb620bdbecf467d49eb13d67;hb=80cf9fb2e6f8117f408850cda5c1a8a932226766;hpb=19d5d4cb6a89c844e298eb65bce6ba0fa9d58b91 diff --git a/README b/README index a5d569028..5222637c2 100644 --- a/README +++ b/README @@ -30,26 +30,120 @@ AUTHOR: LICENSE: LGPLv2.1+ for all code - - except sd-daemon.[ch] and sd-readahead.[ch] which are MIT - - except src/udev/ which is GPLv2.0+ + - except src/shared/MurmurHash2.c which is Public Domain + - except src/shared/siphash24.c which is CC0 Public Domain + - except src/journal/lookup3.c which is Public Domain + - except src/udev/* which is (currently still) GPLv2, GPLv2+ REQUIREMENTS: - Linux kernel >= 2.6.39 - with devtmpfs - with cgroups (but it's OK to disable all controllers) - optional but strongly recommended: autofs4, ipv6 - dbus >= 1.4.0 + Linux kernel >= 3.7 + Linux kernel >= 3.8 for Smack support + + Kernel Config Options: + CONFIG_DEVTMPFS + CONFIG_CGROUPS (it is OK to disable all controllers) + CONFIG_INOTIFY_USER + CONFIG_SIGNALFD + CONFIG_TIMERFD + CONFIG_EPOLL + CONFIG_NET + CONFIG_SYSFS + CONFIG_PROC_FS + CONFIG_FHANDLE (libudev, mount and bind mount handling) + + udev will fail to work with the legacy sysfs layout: + CONFIG_SYSFS_DEPRECATED=n + + Legacy hotplug slows down the system and confuses udev: + CONFIG_UEVENT_HELPER_PATH="" + + Userspace firmware loading is not supported and should + be disabled in the kernel: + CONFIG_FW_LOADER_USER_HELPER=n + + Some udev rules and virtualization detection relies on it: + CONFIG_DMIID + + Support for some SCSI devices serial number retrieval, to + create additional symlinks in /dev/disk/ and /dev/tape: + CONFIG_BLK_DEV_BSG + + Required for PrivateNetwork and PrivateDevices in service units: + CONFIG_NET_NS + CONFIG_DEVPTS_MULTIPLE_INSTANCES + Note that systemd-localed.service and other systemd units use + PrivateNetwork and PrivateDevices so this is effectively required. + + Optional but strongly recommended: + CONFIG_IPV6 + CONFIG_AUTOFS4_FS + CONFIG_TMPFS_XATTR + CONFIG_{TMPFS,EXT4,XFS,BTRFS_FS,...}_POSIX_ACL + CONFIG_SECCOMP + + Required for CPUShares in resource control unit settings + CONFIG_CGROUP_SCHED + CONFIG_FAIR_GROUP_SCHED + + Required for CPUQuota in resource control unit settings + CONFIG_CFS_BANDWIDTH + + For systemd-bootchart, several proc debug interfaces are required: + CONFIG_SCHEDSTATS + CONFIG_SCHED_DEBUG + + For UEFI systems: + CONFIG_EFIVAR_FS + CONFIG_EFI_PARTITION + + Note that kernel auditing is broken when used with systemd's + container code. When using systemd in conjunction with + containers, please make sure to either turn off auditing at + runtime using the kernel command line option "audit=0", or + turn it off at kernel compile time using: + CONFIG_AUDIT=n + If systemd is compiled with libseccomp support on + architectures which do not use socketcall() and where seccomp + is supported (this effectively means x86-64 and ARM, but + excludes 32-bit x86!), then nspawn will now install a + work-around seccomp filter that makes containers boot even + with audit being enabled. This works correctly only on kernels + 3.14 and newer though. TL;DR: turn audit off, still. + + glibc >= 2.14 libcap + libmount >= 2.20 (from util-linux) + libseccomp >= 1.0.0 (optional) + libblkid >= 2.24 (from util-linux) (optional) + libkmod >= 15 (optional) PAM >= 1.1.2 (optional) libcryptsetup (optional) libaudit (optional) libacl (optional) libselinux (optional) liblzma (optional) - tcpwrappers (optional) + liblz4 >= 119 (optional) + libgcrypt (optional) + libqrencode (optional) + libmicrohttpd (optional) + libpython (optional) + libidn (optional) + gobject-introspection > 1.40.0 (optional) + elfutils >= 158 (optional) + make, gcc, and similar tools + + During runtime, you need the following additional + dependencies: + + util-linux >= v2.25 required + dbus >= 1.4.0 (strictly speaking optional, but recommended) + dracut (optional) + PolicyKit (optional) - When you build from git you need the following additional dependencies: + When building from git, you need the following additional + dependencies: + pkg-config docbook-xsl xsltproc automake @@ -59,26 +153,73 @@ REQUIREMENTS: gperf gtkdocize (optional) python (optional) - make, gcc, and similar tools + python-lxml (optional, but required to build the indices) + sphinx (optional) + + When systemd-hostnamed is used, it is strongly recommended to + install nss-myhostname to ensure that, in a world of + dynamically changing hostnames, the hostname stays resolvable + under all circumstances. In fact, systemd-hostnamed will warn + if nss-myhostname is not installed. - During runtime you need the following dependencies: + To build HTML documentation for python-systemd using sphinx, + please first install systemd (using 'make install'), and then + invoke sphinx-build with 'make sphinx-', with + being 'html' or 'latexpdf'. If using DESTDIR for installation, + pass the same DESTDIR to 'make sphinx-html' invocation. - util-linux > v2.18 (requires fsck -l, agetty -s) - sulogin (from sysvinit-tools, optional but recommended) - dracut (optional) +USERS AND GROUPS: + Default udev rules use the following standard system group + names, which need to be resolvable by getgrnam() at any time, + even in the very early boot stages, where no other databases + and network are available: - When systemd-hostnamed is used it is strongly recommended to - install nss-myhostname to ensure that in a world of - dynamically changing hostnames the hostname stays resolveable - under all circumstances. In fact, systemd-hostnamed will warn - if nss-myhostname is not installed. Packagers are encouraged to - add a dependency on nss-myhostname to the package that - includes systemd-hostnamed. + audio, cdrom, dialout, disk, input, kmem, lp, tape, tty, video + + During runtime, the journal daemon requires the + "systemd-journal" system group to exist. New journal files will + be readable by this group (but not writable), which may be used + to grant specific users read access. In addition, system + groups "wheel" and "adm" will be given read-only access to + journal files using systemd-tmpfiles.service. + + The journal gateway daemon requires the + "systemd-journal-gateway" system user and group to + exist. During execution this network facing service will drop + privileges and assume this uid/gid for security reasons. + + Similarly, the NTP daemon requires the "systemd-timesync" system + user and group to exist. - Note that D-Bus can link against libsystemd-login.so, which - results in a cyclic build dependency. To accommodate for this - please build D-Bus without systemd first, then build systemd, - then rebuild D-Bus with systemd support. + Similarly, the network management daemon requires the + "systemd-network" system user and group to exist. + + Similarly, the name resolution daemon requires the + "systemd-resolve" system user and group to exist. + + Similarly, the kdbus dbus1 proxy daemon requires the + "systemd-bus-proxy" system user and group to exist. + +NSS: + systemd ships with three NSS modules: + + nss-myhostname resolves the local hostname to locally + configured IP addresses, as well as "localhost" to + 127.0.0.1/::1. + + nss-resolve enables DNS resolution via the systemd-resolved + DNS/LLMNR caching stub resolver "systemd-resolved". + + nss-mymachines enables resolution of all local containers + registered with machined to their respective IP addresses. + + To make use of these NSS modules, please add them to the + "hosts: " line in /etc/nsswitch.conf. The "resolve" module + should replace the glibc "dns" module in this file. + + The three modules should be used in the following order: + + hosts: files mymachines resolve myhostname WARNINGS: systemd will warn you during boot if /etc/mtab is not a @@ -87,24 +228,27 @@ WARNINGS: systemd will warn you during boot if /usr is on a different file system than /. While in systemd itself very little will - break if /usr is on a separate partition many of its + break if /usr is on a separate partition, many of its dependencies very likely will break sooner or later in one - form or another. For example udev rules tend to refer to + form or another. For example, udev rules tend to refer to binaries in /usr, binaries that link to libraries in /usr or binaries that refer to data files in /usr. Since these - breakages are not always directly visible systemd will warn + breakages are not always directly visible, systemd will warn about this, since this kind of file system setup is not really supported anymore by the basic set of Linux OS components. + systemd requires that the /run mount point exists. systemd also + requires that /var/run is a a symlink to /run. + For more information on this issue consult http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken + To run systemd under valgrind, compile with VALGRIND defined + (e.g. ./configure CPPFLAGS='... -DVALGRIND=1'). Otherwise, + false positives will be triggered by code which violates + some rules but is actually safe. + ENGINEERING AND CONSULTING SERVICES: - ProFUSION offers professional - engineering and consulting services for systemd for embedded - and other use. Please contact Gustavo Barbieri - for more information. - - Disclaimer: This notice is not a recommendation or official - endorsement. However, ProFUSION's upstream work has been very - beneficial for the systemd project. + ENDOCODE offers professional + engineering and consulting services for systemd. Please + contact Chris Kühl for more information.