Lennart Poettering
f2341e0a87
This changes log_unit_info() (and friends) to take a real Unit* object insted of just a unit name as parameter. The call will now prefix all logged messages with the unit name, thus allowing the unit name to be dropped from the various passed romat strings, simplifying invocations drastically, and unifying log output across messages. Also, UNIT= vs. USER_UNIT= is now derived from the Manager object attached to the Unit object, instead of getpid(). This has the benefit of correcting the field for --test runs. Also contains a couple of other logging improvements: - Drops a couple of strerror() invocations in favour of using %m. - Not only .mount units now warn if a symlinks exist for the mount point already, .automount units do that too, now. - A few invocations of log_struct() that didn't actually pass any additional structured data have been replaced by simpler invocations of log_unit_info() and friends. - For structured data a new LOG_UNIT_MESSAGE() macro has been added, that works like LOG_MESSAGE() but prefixes the message with the unit name. Similar, there's now LOG_LINK_MESSAGE() and LOG_NETDEV_MESSAGE(). - For structured data new LOG_UNIT_ID(), LOG_LINK_INTERFACE(), LOG_NETDEV_INTERFACE() macros have been added that generate the necessary per object fields. The old log_unit_struct() call has been removed in favour of these new macros used in raw log_struct() invocations. In addition to removing one more function call this allows generated structured log messages that contain two object fields, as necessary for example for network interfaces that are joined into another network interface, and whose messages shall be indexed by both. - The LOG_ERRNO() macro has been removed, in favour of log_struct_errno(). The latter has the benefit of ensuring that %m in format strings is properly resolved to the specified error number. - A number of logging messages have been converted to use log_unit_info() instead of log_info() - The client code in sysv-generator no longer #includes core code from src/core/. - log_unit_full_errno() has been removed, log_unit_full() instead takes an errno now, too. - log_unit_info(), log_link_info(), log_netdev_info() and friends, now avoid double evaluation of their parameters
systemd System and Service Manager
DETAILS:
http://0pointer.de/blog/projects/systemd.html
WEB SITE:
http://www.freedesktop.org/wiki/Software/systemd
GIT:
git://anongit.freedesktop.org/systemd/systemd
ssh://git.freedesktop.org/git/systemd/systemd
GITWEB:
http://cgit.freedesktop.org/systemd/systemd
MAILING LIST:
http://lists.freedesktop.org/mailman/listinfo/systemd-devel
http://lists.freedesktop.org/mailman/listinfo/systemd-commits
IRC:
#systemd on irc.freenode.org
BUG REPORTS:
https://bugs.freedesktop.org/enter_bug.cgi?product=systemd
AUTHOR:
Lennart Poettering
Kay Sievers
...and many others
LICENSE:
LGPLv2.1+ for all code
- 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 >= 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 >= 2.16
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)
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 building from git, you need the following additional
dependencies:
pkg-config
docbook-xsl
xsltproc
automake
autoconf
libtool
intltool
gperf
gtkdocize (optional)
python (optional)
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.
To build HTML documentation for python-systemd using sphinx,
please first install systemd (using 'make install'), and then
invoke sphinx-build with 'make sphinx-<target>', with <target>
being 'html' or 'latexpdf'. If using DESTDIR for installation,
pass the same DESTDIR to 'make sphinx-html' invocation.
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:
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.
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
symlink to /proc/mounts. Please ensure that /etc/mtab is a
proper symlink.
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
dependencies very likely will break sooner or later in one
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
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:
ENDOCODE <https://endocode.com/> offers professional
engineering and consulting services for systemd. Please
contact Chris Kühl <chris@endocode.com> for more information.