aboutsummaryrefslogtreecommitdiffstats
path: root/docs/release/userguide/feature.userguide.rst
blob: c7cece476f7aa874d06a3d45a54febdc613e4fe0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
.. This work is licensed under a Creative Commons Attribution 4.0 International License.
.. http://creativecommons.org/licenses/by/4.0
.. (c) Anuket and others

===================================
OPNFV Barometer User Guide
===================================

Barometer collectd plugins description
---------------------------------------
.. Describe the specific features and how it is realised in the scenario in a brief manner
.. to ensure the user understand the context for the user guide instructions to follow.

Collectd is a daemon which collects system performance statistics periodically
and provides a variety of mechanisms to publish the collected metrics. It
supports more than 90 different input and output plugins. Input plugins
retrieve metrics and publish them to the collectd deamon, while output plugins
publish the data they receive to an end point. collectd also has infrastructure
to support thresholding and notification.

Barometer has enabled the following collectd plugins:

* *dpdkstat plugin*: A read plugin that retrieves stats from the DPDK extended
  NIC stats API.

* *dpdkevents plugin*:  A read plugin that retrieves DPDK link status and DPDK
  forwarding cores liveliness status (DPDK Keep Alive).

* *dpdk_telemetry plugin*:  A read plugin to collect dpdk interface stats and
  application or global stats from dpdk telemetry library. Both 'dpdkstat' and
  'dpdk_telemetry' plugins provides dpdk NIC Stats, but only 'dpdk_telemetry'
  provides the DPDK Application stats. So in other words, 'dpdk_telemetry' is
  an advanced version of dpdkstat. This plugin don't deal with dpdk events.
  So not in related with 'dpdkevents' plugin. The mimimum dpdk version required
  to use this plugin is 19.08.

.. note::
  dpdpkstat and dpdk_telemetry should not be used together. Use dpdk_telemetry
  if your version of dpdk supports it (i.e. DPDK >= 19.08) and use dpdkstat otherwise.
  dpdkstat, dpdkevents and dpdk_telemetry plugins should only be used if your dpdk
  application doesn't already have more relevant metrics available(e.g.ovs_stats).


* `gnocchi plugin`_: A write plugin that pushes the retrieved stats to
  Gnocchi. It's capable of pushing any stats read through collectd to
  Gnocchi, not just the DPDK stats.

* `aodh plugin`_: A notification plugin that pushes events to Aodh, and
  creates/updates alarms appropriately.

* *hugepages plugin*:  A read plugin that retrieves the number of available
  and free hugepages on a platform as well as what is available in terms of
  hugepages per socket.

* *Open vSwitch events Plugin*: A read plugin that retrieves events from OVS.

* *Open vSwitch stats Plugin*: A read plugin that retrieves flow and interface
  stats from OVS.

* *mcelog plugin*: A read plugin that uses mcelog client protocol to check for
  memory Machine Check Exceptions and sends the stats for reported exceptions.

* *PMU plugin*: A read plugin that provides performance counters data on
  Intel CPUs using Linux perf interface.

* *RDT plugin*: A read plugin that provides the last level cache utilization and
  memory bandwidth utilization.

* *virt*: A read plugin that uses virtualization API *libvirt* to gather
  statistics about virtualized guests on a system directly from the hypervisor,
  without a need to install collectd instance on the guest.

* *SNMP Agent*: A write plugin that will act as a AgentX subagent that receives
  and handles queries from SNMP master agent and returns the data collected
  by read plugins. The SNMP Agent plugin handles requests only for OIDs
  specified in configuration file. To handle SNMP queries the plugin gets data
  from collectd and translates requested values from collectd's internal format
  to SNMP format. Supports SNMP: get, getnext and walk requests.

All the plugins above are available on the collectd main branch, except for
the Gnocchi and Aodh plugins as they are Python-based plugins and only C
plugins are accepted by the collectd community. The Gnocchi and Aodh plugins
live in the OpenStack repositories.

.. TODO: Update this to reflect merging of these PRs
Other plugins existing as a pull request into collectd main:

* *Legacy/IPMI*: A read plugin that reports platform thermals, voltages,
  fanspeed, current, flow, power etc. Also, the plugin monitors Intelligent
  Platform Management Interface (IPMI) System Event Log (SEL) and sends the
  appropriate notifications based on monitored SEL events.

* *PCIe AER*: A read plugin that monitors PCIe standard and advanced errors and
  sends notifications about those errors.


Third party application in Barometer repository:

* *Open vSwitch PMD stats*: An aplication that retrieves PMD stats from OVS. It is run
  through exec plugin.

**Plugins and application included in the Euphrates release:**

Write Plugins: aodh plugin, SNMP agent plugin, gnocchi plugin.

Read Plugins/application: Intel RDT plugin, virt plugin, Open vSwitch stats plugin,
Open vSwitch PMD stats application.

Collectd capabilities and usage
------------------------------------
.. Describe the specific capabilities and usage for <XYZ> feature.
.. Provide enough information that a user will be able to operate the feature on a deployed scenario.

.. note:: Plugins included in the OPNFV E release will be built-in for Apex integration
 and can be configured as shown in the examples below.

 The collectd plugins in OPNFV are configured with reasonable defaults, but can
 be overridden.

Building all Barometer upstreamed plugins from scratch
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The plugins that have been merged to the collectd main branch can all be
built and configured through the barometer repository.

.. note::
 * sudo permissions are required to install collectd.
 * These instructions are for Centos 7.

To build all the upstream plugins, clone the barometer repo:

.. code:: c

    $ git clone https://gerrit.opnfv.org/gerrit/barometer

To install collectd as a service and install all it's dependencies:

.. code:: bash

    $ cd barometer/systems && ./build_base_machine.sh

This will install collectd as a service and the base install directory
will be /opt/collectd.

Sample configuration files can be found in '/opt/collectd/etc/collectd.conf.d'

.. note::
  If you don't want to use one of the Barometer plugins, simply remove the
  sample config file from '/opt/collectd/etc/collectd.conf.d'
.. note::
  If you plan on using the Exec plugin (for OVS_PMD_STATS or for executing scripts
  on notification generation), the plugin requires a non-root user to execute scripts.
  By default, `collectd_exec` user is used in the exec.conf provided in the sample
  configurations directory under src/collectd in the Barometer repo. These scripts *DO NOT* create this user.
  You need to create this user or modify the configuration in the sample configurations directory
  under src/collectd to use another existing non root user before  running build_base_machine.sh.

.. note::
  If you are using any Open vSwitch plugins you need to run:

.. code:: bash

    $ sudo ovs-vsctl set-manager ptcp:6640

After this, you should be able to start collectd as a service

.. code:: bash

    $ sudo systemctl status collectd

If you want to use granfana to display the metrics you collect, please see:
`grafana guide`_

For more information on configuring and installing OpenStack plugins for
collectd, check out the `collectd-openstack-plugins GSG`_.

Below is the per plugin installation and configuration guide, if you only want
to install some/particular plugins.

DPDK plugins
^^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: main

Dependencies: DPDK (https://dpdk.org/)

.. note:: DPDK statistics plugin requires DPDK version 16.04 or later.

To build and install DPDK to /usr please see:
https://github.com/collectd/collectd/blob/main/docs/BUILD.dpdkstat.md

Building and installing collectd:

.. code:: bash

    $ git clone https://github.com/collectd/collectd.git
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --enable-debug
    $ make
    $ sudo make install

.. note:: If DPDK was installed in a non standard location you will need to
    specify paths to the header files and libraries using *LIBDPDK_CPPFLAGS* and
    *LIBDPDK_LDFLAGS*. You will also need to add the DPDK library symbols to the
    shared library path using *ldconfig*. Note that this update to the shared
    library path is not persistant (i.e. it will not survive a reboot).

Example of specifying custom paths to DPDK headers and libraries:

.. code:: bash

    $ ./configure LIBDPDK_CPPFLAGS="path to DPDK header files" LIBDPDK_LDFLAGS="path to DPDK libraries"

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.
To configure the dpdkstats plugin you need to modify the configuration file to
include:

.. code:: bash

    LoadPlugin dpdkstat
    <Plugin dpdkstat>
       Coremask "0xf"
       ProcessType "secondary"
       FilePrefix "rte"
       EnabledPortMask 0xffff
       PortName "interface1"
       PortName "interface2"
    </Plugin>


To configure the dpdkevents plugin you need to modify the configuration file to
include:

.. code:: bash

    <LoadPlugin dpdkevents>
      Interval 1
    </LoadPlugin>

    <Plugin "dpdkevents">
      <EAL>
        Coremask "0x1"
        MemoryChannels "4"
        FilePrefix "rte"
      </EAL>
      <Event "link_status">
        SendEventsOnUpdate false
        EnabledPortMask 0xffff
        SendNotification true
      </Event>
      <Event "keep_alive">
        SendEventsOnUpdate false
        LCoreMask "0xf"
        KeepAliveShmName "/dpdk_keepalive_shm_name"
        SendNotification true
      </Event>
    </Plugin>

.. note:: Currently, the DPDK library doesn’t support API to de-initialize
 the DPDK resources allocated on the initialization. It means, the collectd
 plugin will not be able to release the allocated DPDK resources
 (locks/memory/pci bindings etc.) correctly on collectd shutdown or reinitialize
 the DPDK library if primary DPDK process is restarted. The only way to release
 those resources is to terminate the process itself. For this reason, the plugin
 forks off a separate collectd process. This child process becomes a secondary
 DPDK process which can be run on specific CPU cores configured by user through
 collectd configuration file (“Coremask” EAL configuration option, the
 hexadecimal bitmask of the cores to run on).

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

.. note:: dpdkstat plugin initialization time depends on read interval. It
 requires 5 read cycles to set up internal buffers and states, during that time
 no statistics are submitted. Also, if plugin is running and the number of DPDK
 ports is increased, internal buffers are resized. That requires 3 read cycles
 and no port statistics are submitted during that time.

The Address-Space Layout Randomization (ASLR) security feature in Linux should be
disabled, in order for the same hugepage memory mappings to be present in all
DPDK multi-process applications.

To disable ASLR:

.. code:: bash

    $ sudo echo 0 > /proc/sys/kernel/randomize_va_space

To fully enable ASLR:

.. code:: bash

    $ sudo echo 2 > /proc/sys/kernel/randomize_va_space

.. warning:: Disabling Address-Space Layout Randomization (ASLR) may have security
    implications. It is recommended to be disabled only when absolutely necessary,
    and only when all implications of this change have been understood.

For more information on multi-process support, please see:
https://doc.dpdk.org/guides/prog_guide/multi_proc_support.html

**DPDK stats plugin limitations:**

1. The DPDK primary process application should use the same version of DPDK
   that collectd DPDK plugin is using;

2. L2 statistics are only supported;

3. The plugin has been tested on Intel NIC’s only.

**DPDK stats known issues:**

* DPDK port visibility

  When network port controlled by Linux is bound to DPDK driver, the port
  will not be available in the OS. It affects the SNMP write plugin as those
  ports will not be present in standard IF-MIB. Thus, additional work is
  required to be done to support DPDK ports and statistics.

**DPDK telemetry plugin**

Please refer to https://wiki.anuket.io/display/HOME/DPDK+Telemetry+Plugin

Hugepages Plugin
^^^^^^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: main

Dependencies: None, but assumes hugepages are configured.

To configure some hugepages:

.. code:: bash

   $ sudo mkdir -p /mnt/huge
   $ sudo mount -t hugetlbfs nodev /mnt/huge
   $ sudo bash -c "echo 14336 > /sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages"

Building and installing collectd:

.. code:: bash

    $ git clone https://github.com/collectd/collectd.git
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --enable-hugepages --enable-debug
    $ make
    $ sudo make install

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.
To configure the hugepages plugin you need to modify the configuration file to
include:

.. code:: bash

    LoadPlugin hugepages
    <Plugin hugepages>
        ReportPerNodeHP  true
        ReportRootHP     true
        ValuesPages      true
        ValuesBytes      false
        ValuesPercentage false
    </Plugin>

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

Intel PMU Plugin
^^^^^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: main

Dependencies:

  * PMU tools (jevents library) https://github.com/andikleen/pmu-tools

To be suitable for use in collectd plugin shared library *libjevents* should be
compiled as position-independent code. To do this add the following line to
*pmu-tools/jevents/Makefile*:

.. code:: bash

    CFLAGS += -fPIC

Building and installing *jevents* library:

.. code:: bash

    $ git clone https://github.com/andikleen/pmu-tools.git
    $ cd pmu-tools/jevents/
    $ make
    $ sudo make install

Download the Hardware Events that are relevant to your CPU, download the appropriate
CPU event list json file:

.. code:: bash

    $ wget https://raw.githubusercontent.com/andikleen/pmu-tools/main/event_download.py
    $ python event_download.py

This will download the json files to the location: $HOME/.cache/pmu-events/. If you don't want to
download these files to the aforementioned location, set the environment variable XDG_CACHE_HOME to
the location you want the files downloaded to.

Building and installing collectd:

.. code:: bash

    $ git clone https://github.com/collectd/collectd.git
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --with-libjevents=/usr/local --enable-debug
    $ make
    $ sudo make install

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.
To configure the PMU plugin you need to modify the configuration file to
include:

.. code:: bash

    <LoadPlugin intel_pmu>
      Interval 1
    </LoadPlugin>
    <Plugin "intel_pmu">
      ReportHardwareCacheEvents true
      ReportKernelPMUEvents true
      ReportSoftwareEvents true
      Cores ""
    </Plugin>

If you want to monitor Intel CPU specific CPU events, make sure to enable the
additional two options shown below:

.. code:: bash

    <Plugin intel_pmu>
     ReportHardwareCacheEvents true
     ReportKernelPMUEvents true
     ReportSoftwareEvents true
     EventList "$HOME/.cache/pmu-events/GenuineIntel-6-2D-core.json"
     HardwareEvents "L2_RQSTS.CODE_RD_HIT,L2_RQSTS.CODE_RD_MISS" "L2_RQSTS.ALL_CODE_RD"
     Cores ""
    </Plugin>

.. note::
    If you set XDG_CACHE_HOME to anything other than the variable above - you will need to modify
    the path for the EventList configuration.

Use "Cores" option to monitor metrics only for configured cores. If an empty string is provided
as value for this field default cores configuration is applied - that is all available cores
are monitored separately. To limit monitoring to cores 0-7 set the option as shown below:

.. code:: bash

    Cores "[0-7]"

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

.. note::

    The plugin opens file descriptors whose quantity depends on number of
    monitored CPUs and number of monitored counters. Depending on configuration,
    it might be required to increase the limit on the number of open file
    descriptors allowed. This can be done using 'ulimit -n' command. If collectd
    is executed as a service 'LimitNOFILE=' directive should be defined in
    [Service] section of *collectd.service* file.

Intel RDT Plugin
^^^^^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: main

Dependencies:

  * PQoS/Intel RDT library https://github.com/intel/intel-cmt-cat
  * msr kernel module

Building and installing PQoS/Intel RDT library:

.. code:: bash

    $ git clone https://github.com/intel/intel-cmt-cat
    $ cd intel-cmt-cat
    $ make
    $ make install PREFIX=/usr

You will need to insert the msr kernel module:

.. code:: bash

    $ modprobe msr

Building and installing collectd:

.. code:: bash

    $ git clone https://github.com/collectd/collectd.git
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --with-libpqos=/usr/ --enable-debug
    $ make
    $ sudo make install

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.
To configure the RDT plugin you need to modify the configuration file to
include:

.. code:: bash

    <LoadPlugin intel_rdt>
      Interval 1
    </LoadPlugin>
    <Plugin "intel_rdt">
      Cores ""
    </Plugin>

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

IPMI Plugin
^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: feat_ipmi_events, feat_ipmi_analog

Dependencies: OpenIPMI library (http://openipmi.sourceforge.net/)

The IPMI plugin is already implemented in the latest collectd and sensors
like temperature, voltage, fanspeed, current are already supported there.
The list of supported IPMI sensors has been extended and sensors like flow,
power are supported now. Also, a System Event Log (SEL) notification feature
has been introduced.

* The feat_ipmi_events branch includes new SEL feature support in collectd
  IPMI plugin. If this feature is enabled, the collectd IPMI plugin will
  dispatch notifications about new events in System Event Log.

* The feat_ipmi_analog branch includes the support of extended IPMI sensors in
  collectd IPMI plugin.

**Install dependencies**

On Centos, install OpenIPMI library:

.. code:: bash

    $ sudo yum install OpenIPMI ipmitool

Anyway, it's recommended to use the latest version of the OpenIPMI library as
it includes fixes of known issues which aren't included in standard OpenIPMI
library package. The latest version of the library can be found at
https://sourceforge.net/p/openipmi/code/ci/master/tree/. Steps to install the
library from sources are described below.

Remove old version of OpenIPMI library:

.. code:: bash

    $ sudo yum remove OpenIPMI ipmitool

Build and install OpenIPMI library:

.. code:: bash

    $ git clone https://git.code.sf.net/p/openipmi/code openipmi-code
    $ cd openipmi-code
    $ autoreconf --install
    $ ./configure --prefix=/usr
    $ make
    $ sudo make install

Add the directory containing ``OpenIPMI*.pc`` files to the ``PKG_CONFIG_PATH``
environment variable:

.. code:: bash

    export PKG_CONFIG_PATH=/usr/lib/pkgconfig

Enable IPMI support in the kernel:

.. code:: bash

    $ sudo modprobe ipmi_devintf
    $ sudo modprobe ipmi_si

.. note::
  If HW supports IPMI, the ``/dev/ipmi0`` character device will be
  created.

Clone and install the collectd IPMI plugin:

.. code:: bash

    $ git clone https://github.com/collectd/collectd
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --enable-debug
    $ make
    $ sudo make install

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.
To configure the IPMI plugin you need to modify the file to include:

.. code:: bash

    LoadPlugin ipmi
    <Plugin ipmi>
       <Instance "local">
         SELEnabled true # only feat_ipmi_events branch supports this
       </Instance>
    </Plugin>

.. note::
  By default, IPMI plugin will read all available analog sensor values,
  dispatch the values to collectd and send SEL notifications.

For more information on the IPMI plugin parameters and SEL feature configuration,
please see: https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

Extended analog sensors support doesn't require additional configuration. The usual
collectd IPMI documentation can be used:

- https://collectd.org/wiki/index.php/Plugin:IPMI
- https://collectd.org/documentation/manpages/collectd.conf.5.shtml#plugin_ipmi

IPMI documentation:

- https://www.kernel.org/doc/Documentation/IPMI.txt
- https://www.intel.com/content/www/us/en/products/docs/servers/ipmi/ipmi-second-gen-interface-spec-v2-rev1-1.html

Mcelog Plugin
^^^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: main

Dependencies: mcelog

Start by installing mcelog.

.. note::
  The kernel has to have CONFIG_X86_MCE enabled. For 32bit kernels you
  need atleast a 2.6,30 kernel.

On Centos:

.. code:: bash

    $ sudo yum install mcelog

Or build from source

.. code:: bash

    $ git clone https://git.kernel.org/pub/scm/utils/cpu/mce/mcelog.git
    $ cd mcelog
    $ make
    ... become root ...
    $ make install
    $ cp mcelog.service /etc/systemd/system/
    $ systemctl enable mcelog.service
    $ systemctl start mcelog.service


Verify you got a /dev/mcelog. You can verify the daemon is running completely
by running:

.. code:: bash

     $ mcelog --client

This should query the information in the running daemon. If it prints nothing
that is fine (no errors logged yet). More info @
http://www.mcelog.org/installation.html

Modify the mcelog configuration file "/etc/mcelog/mcelog.conf" to include or
enable:

.. code:: bash

    socket-path = /var/run/mcelog-client
    [dimm]
    dimm-tracking-enabled = yes
    dmi-prepopulate = yes
    uc-error-threshold = 1 / 24h
    ce-error-threshold = 10 / 24h

    [socket]
    socket-tracking-enabled = yes
    mem-uc-error-threshold = 100 / 24h
    mem-ce-error-threshold = 100 / 24h
    mem-ce-error-log = yes

    [page]
    memory-ce-threshold = 10 / 24h
    memory-ce-log = yes
    memory-ce-action = soft

    [trigger]
    children-max = 2
    directory = /etc/mcelog


Clone and install the collectd mcelog plugin:

.. code:: bash

    $ git clone https://github.com/collectd/collectd
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --enable-debug
    $ make
    $ sudo make install

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.
To configure the mcelog plugin you need to modify the configuration file to
include:

.. code:: bash

    <LoadPlugin mcelog>
      Interval 1
    </LoadPlugin>
    <Plugin mcelog>
      <Memory>
        McelogClientSocket "/var/run/mcelog-client"
        PersistentNotification false
      </Memory>
      #McelogLogfile "/var/log/mcelog"
    </Plugin>

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

Simulating a Machine Check Exception can be done in one of 3 ways:

* Running $make test in the mcelog cloned directory - mcelog test suite
* using mce-inject
* using mce-test

**mcelog test suite:**

It is always a good idea to test an error handling mechanism before it is
really needed. mcelog includes a test suite. The test suite relies on
mce-inject which needs to be installed and in $PATH.

You also need the mce-inject kernel module configured (with
CONFIG_X86_MCE_INJECT=y), compiled, installed and loaded:

.. code:: bash

    $ modprobe mce-inject

Then you can run the mcelog test suite with

.. code:: bash

    $ make test

This will inject different classes of errors and check that the mcelog triggers
runs. There will be some kernel messages about page offlining attempts. The
test will also lose a few pages of memory in your system (not significant).

.. note::
  This test will kill any running mcelog, which needs to be restarted
  manually afterwards.

**mce-inject:**

A utility to inject corrected, uncorrected and fatal machine check exceptions

.. code:: bash

    $ git clone https://git.kernel.org/pub/scm/utils/cpu/mce/mce-inject.git
    $ cd mce-inject
    $ make
    $ modprobe mce-inject

Modify the test/corrected script to include the following:

.. code:: bash

    CPU 0 BANK 0
    STATUS 0xcc00008000010090
    ADDR 0x0010FFFFFFF

Inject the error:
.. code:: bash

    $ ./mce-inject < test/corrected

.. note::
  The uncorrected and fatal scripts under test will cause a platform reset.
  Only the fatal script generates the memory errors**. In order to  quickly
  emulate uncorrected memory errors and avoid host reboot following test errors
  from mce-test suite can be injected:

.. code:: bash

       $ mce-inject  mce-test/cases/coverage/soft-inj/recoverable_ucr/data/srao_mem_scrub

**mce-test:**

In addition a more in-depth test of the Linux kernel machine check facilities
can be done with the mce-test test suite. mce-test supports testing uncorrected
error handling, real error injection, handling of different soft offlining
cases, and other tests.

**Corrected memory error injection:**

To inject corrected memory errors:

* Remove sb_edac and edac_core kernel modules: rmmod sb_edac rmmod edac_core
* Insert einj module: modprobe einj param_extension=1
* Inject an error by specifying details (last command should be repeated at least two times):

.. code:: bash

    $ APEI_IF=/sys/kernel/debug/apei/einj
    $ echo 0x8 > $APEI_IF/error_type
    $ echo 0x01f5591000 > $APEI_IF/param1
    $ echo 0xfffffffffffff000 > $APEI_IF/param2
    $ echo 1 > $APEI_IF/notrigger
    $ echo 1 > $APEI_IF/error_inject

* Check the MCE statistic: mcelog --client. Check the mcelog log for injected error details: less /var/log/mcelog.

Open vSwitch Plugins
^^^^^^^^^^^^^^^^^^^^^
OvS Plugins Repo: https://github.com/collectd/collectd

OvS Plugins Branch: main

OvS Events MIBs: The SNMP OVS interface link status is provided by standard
IF-MIB (http://www.net-snmp.org/docs/mibs/IF-MIB.txt)

Dependencies: Open vSwitch, Yet Another JSON Library (https://github.com/lloyd/yajl)

On Centos, install the dependencies and Open vSwitch:

.. code:: bash

    $ sudo yum install yajl-devel

Steps to install Open vSwtich can be found at
https://docs.openvswitch.org/en/latest/intro/install/fedora/

Start the Open vSwitch service:

.. code:: bash

    $ sudo service openvswitch-switch start

Configure the ovsdb-server manager:

.. code:: bash

    $ sudo ovs-vsctl set-manager ptcp:6640

Clone and install the collectd ovs plugin:

.. code:: bash

    $ git clone $REPO
    $ cd collectd
    $ git checkout main
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --enable-debug
    $ make
    $ sudo make install

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.
To configure the OVS events plugin you need to modify the configuration file to include:

.. code:: bash

    <LoadPlugin ovs_events>
       Interval 1
    </LoadPlugin>
    <Plugin ovs_events>
       Port "6640"
       Address "127.0.0.1"
       Socket "/var/run/openvswitch/db.sock"
       Interfaces "br0" "veth0"
       SendNotification true
    </Plugin>

To configure the OVS stats plugin you need to modify the configuration file
to include:

.. code:: bash

    <LoadPlugin ovs_stats>
       Interval 1
    </LoadPlugin>
    <Plugin ovs_stats>
       Port "6640"
       Address "127.0.0.1"
       Socket "/var/run/openvswitch/db.sock"
       Bridges "br0"
    </Plugin>

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

OVS PMD stats
^^^^^^^^^^^^^^
Repo: https://gerrit.opnfv.org/gerrit/barometer

Prequistes:
1. Open vSwitch dependencies are installed.
2. Open vSwitch service is running.
3. Ovsdb-server manager is configured.
You can refer `Open vSwitch Plugins`_ section above for each one of them.

OVS PMD stats application is run through the exec plugin.

To configure the OVS PMD stats application you need to modify the exec plugin configuration
to include:

.. code:: bash

    <LoadPlugin exec>
       Interval 1
    </LoadPlugin
    <Plugin exec>
        Exec "user:group" "<path to ovs_pmd_stat.sh>"
    </Plugin>

.. note:: Exec plugin configuration has to be changed to use appropriate user before starting collectd service.

ovs_pmd_stat.sh calls the script for OVS PMD stats application with its argument:

.. code:: bash

     sudo python /usr/local/src/ovs_pmd_stats.py" "--socket-pid-file"
     "/var/run/openvswitch/ovs-vswitchd.pid"

SNMP Agent Plugin
^^^^^^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: main

Dependencies: NET-SNMP library

Start by installing net-snmp and dependencies.

On Centos 7:

.. code:: bash

    $ sudo yum install net-snmp net-snmp-libs net-snmp-utils net-snmp-devel
    $ sudo systemctl start snmpd.service

go to the `snmp configuration`_ steps.

From source:

Clone and build net-snmp:

.. code:: bash

    $ git clone https://github.com/haad/net-snmp.git
    $ cd net-snmp
    $ ./configure --with-persistent-directory="/var/net-snmp" --with-systemd --enable-shared --prefix=/usr
    $ make

Become root

.. code:: bash

    $ make install

Copy default configuration to persistent folder:

.. code:: bash

    $ cp EXAMPLE.conf /usr/share/snmp/snmpd.conf

Set library path and default MIB configuration:

.. code:: bash

    $ cd ~/
    $ echo export LD_LIBRARY_PATH=/usr/lib >> .bashrc
    $ net-snmp-config --default-mibdirs
    $ net-snmp-config --snmpconfpath

Configure snmpd as a service:

.. code:: bash

    $ cd net-snmp
    $ cp ./dist/snmpd.service /etc/systemd/system/
    $ systemctl enable snmpd.service
    $ systemctl start snmpd.service

.. _`snmp configuration`:

Add the following line to snmpd.conf configuration file
``/etc/snmp/snmpd.conf`` to make all OID tree visible for SNMP clients:

.. code:: bash

    view    systemview    included   .1

To verify that SNMP is working you can get IF-MIB table using SNMP client
to view the list of Linux interfaces:

.. code:: bash

    $ snmpwalk -v 2c -c public localhost IF-MIB::interfaces

Get the default MIB location:

.. code:: bash

    $ net-snmp-config --default-mibdirs
    /opt/stack/.snmp/mibs:/usr/share/snmp/mibs

Install Intel specific MIBs (if needed) into location received by
``net-snmp-config`` command (e.g. ``/usr/share/snmp/mibs``).

.. code:: bash

    $ git clone https://gerrit.opnfv.org/gerrit/barometer.git
    $ sudo cp -f barometer/mibs/*.txt /usr/share/snmp/mibs/
    $ sudo systemctl restart snmpd.service

Clone and install the collectd snmp_agent plugin:

.. code:: bash

    $ cd ~
    $ git clone https://github.com/collectd/collectd
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --enable-debug --enable-snmp --with-libnetsnmp
    $ make
    $ sudo make install

This will install collectd to default folder ``/opt/collectd``. The collectd
configuration file (``collectd.conf``) can be found at ``/opt/collectd/etc``.

**SNMP Agent plugin is a generic plugin and cannot work without configuration**.
To configure the snmp_agent plugin you need to modify the configuration file to
include OIDs mapped to collectd types. The following example maps scalar
memAvailReal OID to value represented as free memory type of memory plugin:

.. code:: bash

    LoadPlugin snmp_agent
    <Plugin "snmp_agent">
      <Data "memAvailReal">
        Plugin "memory"
        Type "memory"
        TypeInstance "free"
        OIDs "1.3.6.1.4.1.2021.4.6.0"
      </Data>
    </Plugin>


The ``snmpwalk`` command can be used to validate the collectd configuration:

.. code:: bash

    $ snmpwalk -v 2c -c public localhost 1.3.6.1.4.1.2021.4.6.0
    UCD-SNMP-MIB::memAvailReal.0 = INTEGER: 135237632 kB


**Limitations**

* Object instance with Counter64 type is not supported in SNMPv1. When GetNext
  request is received, Counter64 type objects will be skipped. When Get
  request is received for Counter64 type object, the error will be returned.
* Interfaces that are not visible to Linux like DPDK interfaces cannot be
  retreived using standard IF-MIB tables.

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

For more details on AgentX subagent, please see:
http://www.net-snmp.org/tutorial/tutorial-5/toolkit/demon/

.. _virt-plugin:

virt plugin
^^^^^^^^^^^^
Repo: https://github.com/collectd/collectd

Branch: main

Dependencies: libvirt (https://libvirt.org/), libxml2

On Centos, install the dependencies:

.. code:: bash

    $ sudo yum install libxml2-devel libpciaccess-devel yajl-devel device-mapper-devel

Install libvirt:

.. note:: libvirt version in package manager might be quite old and offer only
    limited functionality. Hence, building and installing libvirt from sources
    is recommended. Detailed instructions can bet found at:
    https://libvirt.org/compiling.html

.. code:: bash

    $ sudo yum install libvirt-devel

Certain metrics provided by the plugin have a requirement on a minimal version of
the libvirt API. *File system information* statistics require a *Guest Agent (GA)*
to be installed and configured in a VM. User must make sure that installed GA
version supports retrieving file system information. Number of *Performance monitoring events*
metrics depends on running libvirt daemon version.

.. note:: Please keep in mind that RDT metrics (part of *Performance monitoring
    events*) have to be supported by hardware. For more details on hardware support,
    please see:
    https://github.com/intel/intel-cmt-cat

    Additionally perf metrics **cannot** be collected if *Intel RDT* plugin is enabled.

libvirt version can be checked with following commands:

.. code:: bash

    $ virsh --version
    $ libvirtd --version

.. table:: Extended statistics requirements

    +-------------------------------+--------------------------+-------------+
    | Statistic                     | Min. libvirt API version | Requires GA |
    +===============================+==========================+=============+
    | Domain reason                 | 0.9.2                    | No          |
    +-------------------------------+--------------------------+-------------+
    | Disk errors                   | 0.9.10                   | No          |
    +-------------------------------+--------------------------+-------------+
    | Job statistics                | 1.2.9                    | No          |
    +-------------------------------+--------------------------+-------------+
    | File system information       | 1.2.11                   | Yes         |
    +-------------------------------+--------------------------+-------------+
    | Performance monitoring events | 1.3.3                    | No          |
    +-------------------------------+--------------------------+-------------+

Start libvirt daemon:

.. code:: bash

    $ systemctl start libvirtd

Create domain (VM) XML configuration file. For more information on domain XML
format and examples, please see:
https://libvirt.org/formatdomain.html

.. note:: Installing additional hypervisor dependencies might be required before
    deploying virtual machine.

Create domain, based on created XML file:

.. code:: bash

    $ virsh define DOMAIN_CFG_FILE.xml

Start domain:

.. code:: bash

    $ virsh start DOMAIN_NAME

Check if domain is running:

.. code:: bash

    $ virsh list

Check list of available *Performance monitoring events* and their settings:

.. code:: bash

    $ virsh perf DOMAIN_NAME

Enable or disable *Performance monitoring events* for domain:

.. code:: bash

    $ virsh perf DOMAIN_NAME [--enable | --disable] EVENT_NAME --live

Clone and install the collectd virt plugin:

.. code:: bash

    $ git clone $REPO
    $ cd collectd
    $ ./build.sh
    $ ./configure --enable-syslog --enable-logfile --enable-debug
    $ make
    $ sudo make install

Where ``$REPO`` is equal to information provided above.

This will install collectd to ``/opt/collectd``. The collectd configuration file
``collectd.conf`` can be found at ``/opt/collectd/etc``.
To load the virt plugin user needs to modify the configuration file to include:

.. code:: bash

    LoadPlugin virt

Additionally, user can specify plugin configuration parameters in this file,
such as connection URL, domain name and much more. By default extended virt plugin
statistics are disabled. They can be enabled with ``ExtraStats`` option.

.. code:: bash

    <Plugin virt>
       RefreshInterval 60
       ExtraStats "cpu_util disk disk_err domain_state fs_info job_stats_background pcpu perf vcpupin"
    </Plugin>

For more information on the plugin parameters, please see:
https://github.com/collectd/collectd/blob/main/src/collectd.conf.pod

.. _install-collectd-as-a-service:

Installing collectd as a service
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
**NOTE**: In an OPNFV installation, collectd is installed and configured as a
service.

Collectd service scripts are available in the collectd/contrib directory.
To install collectd as a service:

.. code:: bash

    $ sudo cp contrib/systemd.collectd.service /etc/systemd/system/
    $ cd /etc/systemd/system/
    $ sudo mv systemd.collectd.service collectd.service
    $ sudo chmod +x collectd.service

Modify collectd.service

.. code:: bash

    [Service]
    ExecStart=/opt/collectd/sbin/collectd
    EnvironmentFile=-/opt/collectd/etc/
    EnvironmentFile=-/opt/collectd/etc/
    CapabilityBoundingSet=CAP_SETUID CAP_SETGID

Reload

.. code:: bash

    $ sudo systemctl daemon-reload
    $ sudo systemctl start collectd.service
    $ sudo systemctl status collectd.service should show success

Additional useful plugins
^^^^^^^^^^^^^^^^^^^^^^^^^^

**Exec Plugin** : Can be used to show you when notifications are being
generated by calling a bash script that dumps notifications to file. (handy
for debug). Modify /opt/collectd/etc/collectd.conf:

.. code:: bash

   LoadPlugin exec
   <Plugin exec>
   #   Exec "user:group" "/path/to/exec"
      NotificationExec "user" "<path to barometer>/barometer/src/collectd/collectd_sample_configs/write_notification.sh"
   </Plugin>

write_notification.sh (just writes the notification passed from exec through
STDIN to a file (/tmp/notifications)):

.. code:: bash

   #!/bin/bash
   rm -f /tmp/notifications
   while read x y
   do
     echo $x$y >> /tmp/notifications
   done

output to /tmp/notifications should look like:

.. code:: bash

    Severity:WARNING
    Time:1479991318.806
    Host:localhost
    Plugin:ovs_events
    PluginInstance:br-ex
    Type:gauge
    TypeInstance:link_status
    uuid:f2aafeec-fa98-4e76-aec5-18ae9fc74589

    linkstate of "br-ex" interface has been changed to "DOWN"

* **logfile plugin**: Can be used to log collectd activity. Modify
  /opt/collectd/etc/collectd.conf to include:

.. code:: bash

    LoadPlugin logfile
    <Plugin logfile>
        LogLevel info
        File "/var/log/collectd.log"
        Timestamp true
        PrintSeverity false
    </Plugin>


Monitoring Interfaces and Openstack Support
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.. Figure:: monitoring_interfaces.png

   Monitoring Interfaces and Openstack Support

The figure above shows the DPDK L2 forwarding application running on a compute
node, sending and receiving traffic. Collectd is also running on this compute
node retrieving the stats periodically from DPDK through the dpdkstat plugin
and publishing the retrieved stats to OpenStack through the
collectd-openstack-plugins.

To see this demo in action please checkout: `Barometer OPNFV Summit demo`_

For more information on configuring and installing OpenStack plugins for
collectd, check out the `collectd-openstack-plugins GSG`_.

Security
^^^^^^^^^
* AAA – on top of collectd there secure agents like SNMP V3, Openstack agents
  etc. with their own AAA methods.

* Collectd runs as a daemon with root permissions.

* The `Exec plugin`_ allows the execution of external programs but counters the security
  concerns by:

  * Ensuring that only one instance of the program is executed by collectd at any time
  * Forcing the plugin to check that custom programs are never executed with superuser
  privileges.

* Protection of Data in flight:

  * It's recommend to use a minimum version of 4.7 of the Network plugin which provides
    the possibility to cryptographically sign or encrypt the network traffic.
  * Write Redis plugin or the Write MongoDB plugin are recommended to store the data.
  * For more information, please see: https://collectd.org/wiki/index.php?title=Networking_introduction

* Known vulnerabilities include:

  * https://www.cvedetails.com/vulnerability-list/vendor_id-11242/Collectd.html

    * `CVE-2017-7401`_ fixed https://github.com/collectd/collectd/issues/2174 in Version 5.7.2.
    * `CVE-2016-6254`_ fixed https://mailman.verplant.org/pipermail/collectd/2016-July/006838.html
        in Version  5.4.3.
    * `CVE-2010-4336`_ fixed https://mailman.verplant.org/pipermail/collectd/2010-November/004277.html
        in Version 4.10.2.

  * https://www.cvedetails.com/product/20310/Collectd-Collectd.html?vendor_id=11242

* It's recommended to only use collectd plugins from signed packages.

References
^^^^^^^^^^^
.. [1] https://collectd.org/wiki/index.php/Naming_schema
.. [2] https://github.com/collectd/collectd/blob/main/src/daemon/plugin.h
.. [3] https://collectd.org/wiki/index.php/Value_list_t
.. [4] https://collectd.org/wiki/index.php/Data_set
.. [5] https://collectd.org/documentation/manpages/types.db.5.shtml
.. [6] https://collectd.org/wiki/index.php/Data_source
.. [7] https://collectd.org/wiki/index.php/Meta_Data_Interface

.. _Barometer OPNFV Summit demo: https://prezi.com/kjv6o8ixs6se/software-fastpath-service-quality-metrics-demo/
.. _gnocchi plugin: https://github.com/openstack/collectd-openstack-plugins/tree/stable/ocata/
.. _aodh plugin: https://github.com/openstack/collectd-openstack-plugins/tree/stable/ocata/
.. _collectd-openstack-plugins GSG: https://opendev.org/x/collectd-openstack-plugins/src/branch/master/doc/source/GSG.rst
.. _grafana guide: https://wiki.anuket.io/display/HOME/Installing+and+configuring+InfluxDB+and+Grafana+to+display+metrics+with+collectd 
.. _CVE-2017-7401: https://www.cvedetails.com/cve/CVE-2017-7401/
.. _CVE-2016-6254: https://www.cvedetails.com/cve/CVE-2016-6254/
.. _CVE-2010-4336: https://www.cvedetails.com/cve/CVE-2010-4336/
.. _Exec plugin: https://collectd.org/wiki/index.php/Plugin:Exec