1 collectd - System information collection daemon
2 =================================================
8 collectd is a small daemon which collects system information periodically
9 and provides mechanisms to store and monitor the values in a variety of
16 * collectd is able to collect the following data:
19 Apache server utilization: Number of bytes transferred, number of
20 requests handled and detailed scoreboard statistics
23 APC UPS Daemon: UPS charge, load, input/output/battery voltage, etc.
26 Sensors in Macs running Mac OS X / Darwin: Temperature, fan speed and
30 Various sensors in the Aquaero 5 water cooling board made by Aquacomputer.
33 Statistics about Ascent, a free server for the game `World of Warcraft'.
36 Using digital barometer sensor MPL115A2 or MPL3115 from Freescale
37 provides absolute barometric pressure, air pressure reduced to sea level
41 Batterycharge, -current and voltage of ACPI and PMU based laptop
45 Name server and resolver statistics from the `statistics-channel'
46 interface of BIND 9.5, 9,6 and later.
49 CPU accounting information for process groups under Linux.
52 Number of nf_conntrack entries.
55 Number of context switches done by the operating system.
58 CPU utilization: Time spent in the system, user, nice, idle, and related
62 CPU frequency (For laptops with speed step or a similar technology)
65 Parse statistics from websites using regular expressions.
68 Retrieves JSON data via cURL and parses it according to user
72 Retrieves XML data via cURL and parses it according to user
76 Executes SQL statements on various databases and interprets the returned
80 Mountpoint usage (Basically the values `df(1)' delivers)
83 Disk utilization: Sectors read/written, number of read/write actions,
84 average time an IO-operation took to complete.
87 DNS traffic: Query types, response codes, opcodes and traffic/octets
91 Collect individual drbd resource statistics.
94 Email statistics: Count, traffic, spam scores and checks.
95 See collectd-email(5).
98 Amount of entropy available to the system.
101 Network interface card statistics.
104 Values gathered by a custom program or script.
105 See collectd-exec(5).
108 Count the number of files in directories.
111 Linux file-system based caching framework statistics.
114 Receive multicast traffic from Ganglia instances.
117 Hard disk temperatures using hddtempd.
120 Interface traffic: Number of octets, packets and errors for each
124 Iptables' counters: Number of bytes that were matched by a certain
128 IPMI (Intelligent Platform Management Interface) sensors information.
131 IPVS connection statistics (number of connections, octets and packets
132 for each service and destination).
133 See http://www.linuxvirtualserver.org/software/index.html.
136 IRQ counters: Frequency in which certain interrupts occur.
139 Integrates a `Java Virtual Machine' (JVM) to execute plugins in Java
140 bytecode. See “Configuring with libjvm” below.
143 System load average over the last 1, 5 and 15 minutes.
146 Detailed CPU statistics of the “Logical Partitions” virtualization
147 technique built into IBM's POWER processors.
150 Size of “Logical Volumes” (LV) and “Volume Groups” (VG) of Linux'
151 “Logical Volume Manager” (LVM).
154 Queries very detailed usage statistics from wireless LAN adapters and
155 interfaces that use the Atheros chipset and the MadWifi driver.
158 Motherboard sensors: temperature, fan speed and voltage information,
162 Linux software-RAID device information (number of active, failed, spare
166 Query and parse data from a memcache daemon (memcached).
169 Statistics of the memcached distributed caching system.
170 <http://www.danga.com/memcached/>
173 Memory utilization: Memory occupied by running processes, page cache,
174 buffer cache and free.
177 Collects CPU usage, memory usage, temperatures and power consumption from
178 Intel Many Integrated Core (MIC) CPUs.
181 Reads values from Modbus/TCP enabled devices. Supports reading values
182 from multiple "slaves" so gateway devices can be used.
185 Information provided by serial multimeters, such as the `Metex
189 MySQL server statistics: Commands issued, handlers triggered, thread
190 usage, query cache utilization and traffic/octets sent and received.
193 Plugin to query performance values from a NetApp storage system using the
194 “Manage ONTAP” SDK provided by NetApp.
197 Very detailed Linux network interface and routing statistics. You can get
198 (detailed) information on interfaces, qdiscs, classes, and, if you can
199 make use of it, filters.
202 Receive values that were collected by other hosts. Large setups will
203 want to collect the data on one dedicated machine, and this is the
204 plugin of choice for that.
207 NFS Procedures: Which NFS command were called how often. Only NFSv2 and
211 Collects statistics from `nginx' (speak: engine X), a HTTP and mail
215 NTP daemon statistics: Local clock drift, offset to peers, etc.
218 Network UPS tools: UPS current, voltage, power, charge, utilisation,
219 temperature, etc. See upsd(8).
222 Information about Non-Uniform Memory Access (NUMA).
225 Queries routing information from the “Optimized Link State Routing”
228 - onewire (EXPERIMENTAL!)
229 Read onewire sensors using the owcapu library of the owfs project.
230 Please read in collectd.conf(5) why this plugin is experimental.
233 RX and TX of each client in openvpn-status.log (status-version 2).
234 <http://openvpn.net/index.php/documentation/howto.html>
237 Query data from an Oracle database.
240 The perl plugin implements a Perl-interpreter into collectd. You can
241 write your own plugins in Perl and return arbitrary values using this
242 API. See collectd-perl(5).
245 Query statistics from BSD's packet filter "pf".
248 Receive and dispatch timing values from Pinba, a profiling extension for
252 Network latency: Time to reach the default gateway or another given
256 PostgreSQL database statistics: active server connections, transaction
257 numbers, block IO, table row manipulations.
260 PowerDNS name server statistics.
263 Process counts: Number of running, sleeping, zombie, ... processes.
266 Counts various aspects of network protocols such as IP, TCP, UDP, etc.
269 The python plugin implements a Python interpreter into collectd. This
270 makes it possible to write plugins in Python which are executed by
271 collectd without the need to start a heavy interpreter every interval.
272 See collectd-python(5) for details.
275 The redis plugin gathers information from a Redis server, including:
276 uptime, used memory, total connections etc.
279 Query interface and wireless registration statistics from RouterOS.
282 RRDtool caching daemon (RRDcacheD) statistics.
285 System sensors, accessed using lm_sensors: Voltages, temperatures and
289 RX and TX of serial interfaces. Linux only; needs root privileges.
292 Uses libsigrok as a backend, allowing any sigrok-supported device
293 to have its measurements fed to collectd. This includes multimeters,
294 sound level meters, thermometers, and much more.
297 Collect SMART statistics, notably load cycle count, temperature
301 Read values from SNMP (Simple Network Management Protocol) enabled
302 network devices such as switches, routers, thermometers, rack monitoring
303 servers, etc. See collectd-snmp(5).
306 Acts as a StatsD server, reading values sent over the network from StatsD
307 clients and calculating rates and other aggregates out of these values.
310 Pages swapped out onto hard disk or whatever is called `swap' by the OS..
313 Parse table-like structured files.
316 Follows (tails) log files, parses them by lines and submits matched
320 Follows (tails) files in CSV format, parses each line and submits
324 Bytes and operations read and written on tape devices. Solaris only.
327 Number of TCP connections to specific local and remote ports.
330 TeamSpeak2 server statistics.
333 Plugin to read values from `The Energy Detective' (TED).
336 Linux ACPI thermal zone information.
339 Reads the number of records and file size from a running Tokyo Tyrant
343 System uptime statistics.
346 Users currently logged in.
349 Various statistics from Varnish, an HTTP accelerator.
352 CPU, memory, disk and network I/O statistics from virtual machines.
355 Virtual memory statistics, e. g. the number of page-ins/-outs or the
356 number of pagefaults.
359 System resources used by Linux VServers.
360 See <http://linux-vserver.org/>.
363 Link quality of wireless cards. Linux only.
366 Bitrate and frequency of music played with XMMS.
369 Statistics for ZFS' “Adaptive Replacement Cache” (ARC).
371 * Output can be written or sent to various destinations by the following
375 Sends JSON-encoded data to an Advanced Message Queuing Protocol (AMQP)
376 server, such as RabbitMQ.
379 Write to comma separated values (CSV) files. This needs lots of
380 diskspace but is extremely portable and can be analysed with almost
381 every program that can analyse anything. Even Microsoft's Excel..
384 Send the data to a remote host to save the data somehow. This is useful
385 for large setups where the data should be saved by a dedicated machine.
388 Of course the values are propagated to plugins written in Perl, too, so
389 you can easily do weird stuff with the plugins we didn't dare think of
390 ;) See collectd-perl(5).
393 It's possible to implement write plugins in Python using the python
394 plugin. See collectd-python(5) for details.
397 Output to round-robin-database (RRD) files using the RRDtool caching
398 daemon (RRDcacheD) - see rrdcached(1). That daemon provides a general
399 implementation of the caching done by the `rrdtool' plugin.
402 Output to round-robin-database (RRD) files using librrd. See rrdtool(1).
403 This is likely the most popular destination for such values. Since
404 updates to RRD-files are somewhat expensive this plugin can cache
405 updates to the files and write a bunch of updates at once, which lessens
409 One can query the values from the unixsock plugin whenever they're
410 needed. Please read collectd-unixsock(5) for a description on how that's
414 Sends data to Carbon, the storage layer of Graphite using TCP or UDP. It
415 can be configured to avoid logging send errors (especially useful when
419 Sends data OpenTSDB, a scalable no master, no shared state time series
423 Sends the values collected by collectd to a web-server using HTTP POST
424 requests. The transmitted data is either in a form understood by the
425 Exec plugin or formatted in JSON.
428 Sends data to Apache Kafka, a distributed queue.
431 Sends data to MongoDB, a NoSQL database.
434 Sends the values to a Redis key-value database server.
437 Sends data to Riemann, a stream processing and monitoring system.
439 * Logging is, as everything in collectd, provided by plugins. The following
440 plugins keep up informed about what's going on:
443 Writes log messages to a file or STDOUT/STDERR.
446 Log messages are propagated to plugins written in Perl as well.
447 See collectd-perl(5).
450 It's possible to implement log plugins in Python using the python plugin.
451 See collectd-python(5) for details.
454 Logs to the standard UNIX logging mechanism, syslog.
457 Writes log messages formatted as logstash JSON events.
459 * Notifications can be handled by the following plugins:
462 Send a desktop notification to a notification daemon, as defined in
463 the Desktop Notification Specification. To actually display the
464 notifications, notification-daemon is required.
465 See http://www.galago-project.org/specs/notification/.
468 Send an E-mail with the notification message to the configured
472 Execute a program or script to handle the notification.
473 See collectd-exec(5).
476 Writes the notification message to a file or STDOUT/STDERR.
479 Send the notification to a remote host to handle it somehow.
482 Notifications are propagated to plugins written in Perl as well.
483 See collectd-perl(5).
486 It's possible to implement notification plugins in Python using the
487 python plugin. See collectd-python(5) for details.
489 * Value processing can be controlled using the "filter chain" infrastructure
490 and "matches" and "targets". The following plugins are available:
492 - match_empty_counter
493 Match counter values which are currently zero.
496 Match values using a hash function of the hostname.
499 Match values by their identifier based on regular expressions.
502 Match values with an invalid timestamp.
505 Select values by their data sources' values.
507 - target_notification
508 Create and dispatch a notification.
511 Replace parts of an identifier using regular expressions.
514 Scale (multiply) values by an arbitrary value.
517 Set (overwrite) entire parts of an identifier.
519 * Miscellaneous plugins:
522 Selects multiple value lists based on patterns or regular expressions
523 and creates new aggregated values lists from those.
526 Checks values against configured thresholds and creates notifications if
527 values are out of bounds. See collectd-threshold(5) for details.
530 Sets the hostname to a unique identifier. This is meant for setups
531 where each client may migrate to another physical host, possibly going
532 through one or more name changes in the process.
534 * Performance: Since collectd is running as a daemon it doesn't spend much
535 time starting up again and again. With the exception of the exec plugin no
536 processes are forked. Caching in output plugins, such as the rrdtool and
537 network plugins, makes sure your resources are used efficiently. Also,
538 since collectd is programmed multithreaded it benefits from hyper-threading
539 and multicore processors and makes sure that the daemon isn't idle if only
540 one plugin waits for an IO-operation to complete.
542 * Once set up, hardly any maintenance is necessary. Setup is kept as easy
543 as possible and the default values should be okay for most users.
549 * collectd's configuration file can be found at `sysconfdir'/collectd.conf.
550 Run `collectd -h' for a list of built-in defaults. See `collectd.conf(5)'
551 for a list of options and a syntax description.
553 * When the `csv' or `rrdtool' plugins are loaded they'll write the values to
554 files. The usual place for these files is beneath `/var/lib/collectd'.
556 * When using some of the plugins, collectd needs to run as user root, since
557 only root can do certain things, such as craft ICMP packages needed to ping
558 other hosts. collectd should NOT be installed setuid root since it can be
559 used to overwrite valuable files!
561 * Sample scripts to generate graphs reside in `contrib/' in the source
562 package or somewhere near `/usr/share/doc/collectd' in most distributions.
563 Please be aware that those script are meant as a starting point for your
564 own experiments.. Some of them require the `RRDs' Perl module.
565 (`librrds-perl' on Debian) If you have written a more sophisticated
566 solution please share it with us.
568 * The RRAs of the automatically created RRD files depend on the `step'
569 and `heartbeat' settings given. If change these settings you may need to
570 re-create the files, losing all data. Please be aware of that when changing
571 the values and read the rrdtool(1) manpage thoroughly.
574 collectd and chkrootkit
575 -----------------------
577 If you are using the `dns' plugin chkrootkit(1) will report collectd as a
578 packet sniffer ("<iface>: PACKET SNIFFER(/usr/sbin/collectd[<pid>])"). The
579 plugin captures all UDP packets on port 53 to analyze the DNS traffic. In
580 this case, collectd is a legitimate sniffer and the report should be
581 considered to be a false positive. However, you might want to check that
582 this really is collectd and not some other, illegitimate sniffer.
588 To compile collectd from source you will need:
590 * Usual suspects: C compiler, linker, preprocessor, make, ...
592 * A POSIX-threads (pthread) implementation.
593 Since gathering some statistics is slow (network connections, slow devices,
594 etc) collectd is parallelized. The POSIX threads interface is being
595 used and should be found in various implementations for hopefully all
598 * aerotools-ng (optional)
599 Used by the `aquaero' plugin. Currently, the `libaquaero5' library, which
600 is used by the `aerotools-ng' toolkit, is not compiled as a shared object
601 nor does it feature an installation routine. Therefore, you need to point
602 collectd's configure script at the source directory of the `aerotools-ng'
604 <https://github.com/lynix/aerotools-ng>
606 * CoreFoundation.framework and IOKit.framework (optional)
607 For compiling on Darwin in general and the `apple_sensors' plugin in
609 <http://developer.apple.com/corefoundation/>
611 * libclntsh (optional)
612 Used by the `oracle' plugin.
614 * libcredis (optional)
615 Used by the `redis' plugin. Please note that you require a 0.2.2 version
616 or higher. <http://code.google.com/p/credis/>
619 If you want to use the `apache', `ascent', `bind', `curl', `curl_json',
620 `curl_xml', `nginx', or `write_http' plugin.
621 <http://curl.haxx.se/>
624 Used by the `dbi' plugin to connect to various databases.
625 <http://libdbi.sourceforge.net/>
627 * libesmtp (optional)
628 For the `notify_email' plugin.
629 <http://www.stafford.uklinux.net/libesmtp/>
631 * libganglia (optional)
632 Used by the `gmond' plugin to process data received from Ganglia.
633 <http://ganglia.info/>
635 * libgcrypt (optional)
636 Used by the `network' plugin for encryption and authentication.
637 <http://www.gnupg.org/>
640 If present, the `uuid' plugin will check for UUID from HAL.
641 <http://hal.freedesktop.org/>
643 * libi2c-dev (optional)
644 Used for the plugin `barometer', provides just the i2c-dev.h header file
645 for user space i2c development.
648 For querying iptables counters.
649 <http://netfilter.org/>
652 Library that encapsulates the `Java Virtual Machine' (JVM). This library is
653 used by the `java' plugin to execute Java bytecode. See “Configuring with
655 <http://openjdk.java.net/> (and others)
658 Used by the `lvm' plugin.
659 <ftp://sources.redhat.com/pub/lvm2/>
661 * libmemcached (optional)
662 Used by the `memcachec' plugin to connect to a memcache daemon.
663 <http://tangent.org/552/libmemcached.html>
666 Used by the `netlink' plugin.
667 <http://www.netfilter.org/projects/libmnl/>
669 * libmodbus (optional)
670 Used by the `modbus' plugin to communicate with Modbus/TCP devices. The
671 `modbus' plugin works with version 2.0.3 of the library – due to frequent
672 API changes other versions may or may not compile cleanly.
673 <http://www.libmodbus.org/>
675 * libmysqlclient (optional)
676 Unsurprisingly used by the `mysql' plugin.
677 <http://dev.mysql.com/>
679 * libnetapp (optional)
680 Required for the `netapp' plugin.
681 This library is part of the “Manage ONTAP SDK” published by NetApp.
683 * libnetsnmp (optional)
684 For the `snmp' plugin.
685 <http://www.net-snmp.org/>
687 * libnotify (optional)
688 For the `notify_desktop' plugin.
689 <http://www.galago-project.org/>
691 * libopenipmi (optional)
692 Used by the `ipmi' plugin to prove IPMI devices.
693 <http://openipmi.sourceforge.net/>
695 * liboping (optional)
696 Used by the `ping' plugin to send and receive ICMP packets.
697 <http://octo.it/liboping/>
699 * libowcapi (optional)
700 Used by the `onewire' plugin to read values from onewire sensors (or the
702 <http://www.owfs.org/>
705 Used to capture packets by the `dns' plugin.
706 <http://www.tcpdump.org/>
708 * libperfstat (optional)
709 Used by various plugins to gather statistics under AIX.
712 Obviously used by the `perl' plugin. The library has to be compiled with
713 ithread support (introduced in Perl 5.6.0).
714 <http://www.perl.org/>
717 The PostgreSQL C client library used by the `postgresql' plugin.
718 <http://www.postgresql.org/>
720 * libprotobuf-c, protoc-c (optional)
721 Used by the `pinba' plugin to generate a parser for the network packets
722 sent by the Pinba PHP extension, and by the `write_riemann' plugin to
723 generate events to be sent to a Riemann server.
724 <http://code.google.com/p/protobuf-c/>
726 * libpython (optional)
727 Used by the `python' plugin. Currently, Python 2.3 and later and Python 3
729 <http://www.python.org/>
731 * librabbitmq (optional; also called “rabbitmq-c”)
732 Used by the `amqp' plugin for AMQP connections, for example to RabbitMQ.
733 <http://hg.rabbitmq.com/rabbitmq-c/>
735 * librdkafka (optional; also called “rdkafka”)
736 Used by the `write_kafka' plugin for producing messages and sending them
738 <https://github.com/edenhill/librdkafka>
740 * librouteros (optional)
741 Used by the `routeros' plugin to connect to a device running `RouterOS'.
742 <http://octo.it/librouteros/>
745 Used by the `rrdtool' and `rrdcached' plugins. The latter requires RRDtool
746 client support which was added after version 1.3 of RRDtool. Versions 1.0,
747 1.2 and 1.3 are known to work with the `rrdtool' plugin.
748 <http://oss.oetiker.ch/rrdtool/>
750 * librt, libsocket, libkstat, libdevinfo (optional)
751 Various standard Solaris libraries which provide system functions.
752 <http://developers.sun.com/solaris/>
754 * libsensors (optional)
755 To read from `lm_sensors', see the `sensors' plugin.
756 <http://www.lm-sensors.org/>
758 * libsigrok (optional)
759 Used by the `sigrok' plugin. In addition, libsigrok depends on glib,
760 libzip, and optionally (depending on which drivers are enabled) on
761 libusb, libftdi and libudev.
763 * libstatgrab (optional)
764 Used by various plugins to collect statistics on systems other than Linux
766 <http://www.i-scream.org/libstatgrab/>
768 * libtokyotyrant (optional)
769 Used by the `tokyotyrant' plugin.
770 <http://1978th.net/tokyotyrant/>
772 * libupsclient/nut (optional)
773 For the `nut' plugin which queries nut's `upsd'.
774 <http://networkupstools.org/>
777 Collect statistics from virtual machines.
778 <http://libvirt.org/>
781 Parse XML data. This is needed for the `ascent', `bind', `curl_xml' and
783 <http://xmlsoft.org/>
786 <http://www.xmms.org/>
789 Parse JSON data. This is needed for the `curl_json' and `log_logstash'
791 <http://github.com/lloyd/yajl>
793 * libvarnish (optional)
794 Fetches statistics from a Varnish instance. This is needed for the
796 <http://varnish-cache.org>
798 Configuring / Compiling / Installing
799 ------------------------------------
801 To configure, build and install collectd with the default settings, run
802 `./configure && make && make install'. For detailed, generic instructions
803 see INSTALL. For a complete list of configure options and their description,
804 run `./configure --help'.
806 By default, the configure script will check for all build dependencies and
807 disable all plugins whose requirements cannot be fulfilled (any other plugin
808 will be enabled). To enable a plugin, install missing dependencies (see
809 section `Prerequisites' above) and rerun `configure'. If you specify the
810 `--enable-<plugin>' configure option, the script will fail if the depen-
811 dencies for the specified plugin are not met. In that case you can force the
812 plugin to be built using the `--enable-<plugin>=force' configure option.
813 This will most likely fail though unless you're working in a very unusual
814 setup and you really know what you're doing. If you specify the
815 `--disable-<plugin>' configure option, the plugin will not be built. If you
816 specify the `--enable-all-plugins' or `--disable-all-plugins' configure
817 options, all plugins will be enabled or disabled respectively by default.
818 Explicitly enabling or disabling a plugin overwrites the default for the
819 specified plugin. These options are meant for package maintainers and should
820 not be used in everyday situations.
822 By default, collectd will be installed into `/opt/collectd'. You can adjust
823 this setting by specifying the `--prefix' configure option - see INSTALL for
824 details. If you pass DESTDIR=<path> to `make install', <path> will be
825 prefixed to all installation directories. This might be useful when creating
826 packages for collectd.
828 Configuring with libjvm
829 -----------------------
831 To determine the location of the required files of a Java installation is not
832 an easy task, because the locations vary with your kernel (Linux, SunOS, …)
833 and with your architecture (x86, SPARC, …) and there is no ‘java-config’
834 script we could use. Configuration of the JVM library is therefore a bit
837 The easiest way to use the `--with-java=$JAVA_HOME' option, where
838 `$JAVA_HOME' is usually something like:
839 /usr/lib/jvm/java-1.5.0-sun-1.5.0.14
841 The configure script will then use find(1) to look for the following files:
847 If found, appropriate CPP-flags and LD-flags are set and the following
848 library checks succeed.
850 If this doesn't work for you, you have the possibility to specify CPP-flags,
851 C-flags and LD-flags for the ‘Java’ plugin by hand, using the following three
852 (environment) variables:
858 For example (shortened for demonstration purposes):
860 ./configure JAVA_CPPFLAGS="-I$JAVA_HOME/include -I$JAVA_HOME/include/linux"
862 Adding "-ljvm" to the JAVA_LDFLAGS is done automatically, you don't have to
868 To compile correctly collectd needs to be able to initialize static
869 variables to NAN (Not A Number). Some C libraries, especially the GNU
870 libc, have a problem with that.
872 Luckily, with GCC it's possible to work around that problem: One can define
873 NAN as being (0.0 / 0.0) and `isnan' as `f != f'. However, to test this
874 ``implementation'' the configure script needs to compile and run a short
875 test program. Obviously running a test program when doing a cross-
876 compilation is, well, challenging.
878 If you run into this problem, you can use the `--with-nan-emulation'
879 configure option to force the use of this implementation. We can't promise
880 that the compiled binary actually behaves as it should, but since NANs
881 are likely never passed to the libm you have a good chance to be lucky.
883 Likewise, collectd needs to know the layout of doubles in memory, in order
884 to craft uniform network packets over different architectures. For this, it
885 needs to know how to convert doubles into the memory layout used by x86. The
886 configure script tries to figure this out by compiling and running a few
887 small test programs. This is of course not possible when cross-compiling.
888 You can use the `--with-fp-layout' option to tell the configure script which
889 conversion method to assume. Valid arguments are:
891 * `nothing' (12345678 -> 12345678)
892 * `endianflip' (12345678 -> 87654321)
893 * `intswap' (12345678 -> 56781234)
899 For questions, bug reports, development information and basically all other
900 concerns please send an email to collectd's mailing list at
901 <list at collectd.org>.
903 For live discussion and more personal contact visit us in IRC, we're in
904 channel #collectd on freenode.
910 Florian octo Forster <octo at collectd.org>,
911 Sebastian tokkee Harl <sh at tokkee.org>,
912 and many contributors (see `AUTHORS').
914 Please send bug reports and patches to the mailing list, see `Contact'
projects / collectd.git / blob