1PTP4l(8)                    System Manager's Manual                   PTP4l(8)
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NAME

6       ptp4l - PTP Boundary/Ordinary/Transparent Clock
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SYNOPSIS

10       ptp4l  [  -AEP246HSLmqsv  ] [ -f config ] [ -p phc-device ] [ -l print-
11       level ] [ -i interface ] [ long-options ] ...
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DESCRIPTION

15       ptp4l is an implementation of the Precision Time Protocol (PTP) accord‐
16       ing to IEEE standard 1588 for Linux. It implements Boundary Clock (BC),
17       Ordinary Clock (OC), and Transparent Clock (TC).
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OPTIONS

21       -A     Select the delay mechanism automatically.  Start  with  E2E  and
22              switch to P2P when a peer delay request is received.
23
24       -E     Select  the  delay request-response (E2E) mechanism. This is the
25              default mechanism. All clocks on single PTP  communication  path
26              must  use  the  same mechanism. A warning will be printed when a
27              peer delay request is received on port using the E2E mechanism.
28
29       -P     Select the peer delay (P2P) mechanism. A warning will be printed
30              when  a  delay  request is received on port using the P2P mecha‐
31              nism.
32
33       -2     Select the IEEE 802.3 network transport.
34
35       -4     Select the UDP IPv4  network  transport.  This  is  the  default
36              transport.
37
38       -6     Select the UDP IPv6 network transport.
39
40       -H     Select the hardware time stamping. All ports specified by the -i
41              option and in the configuration file must  be  attached  to  the
42              same  PTP  hardware clock (PHC). This is the default time stamp‐
43              ing.
44
45       -S     Select the software time stamping.
46
47       -L     Select the legacy hardware time stamping.
48
49       -f config
50              Read configuration from the  specified  file.  No  configuration
51              file is read by default.
52
53       -i interface
54              Specify  a PTP port, it may be used multiple times. At least one
55              port must be specified by this option or  in  the  configuration
56              file.
57
58       -p phc-device
59              (This option is deprecated.)  Before Linux kernel v3.5 there was
60              no way to discover the PHC  device  associated  with  a  network
61              interface.    This   option   specifies  the  PHC  device  (e.g.
62              /dev/ptp0) to be used when running on legacy kernels.
63
64       -s     Enable the slaveOnly mode.
65
66       -l print-level
67              Set the maximum syslog level of messages which should be printed
68              or sent to the system logger. The default is 6 (LOG_INFO).
69
70       -m     Print messages to the standard output.
71
72       -q     Don't send messages to the system logger.
73
74       -v     Prints the software version and exits.
75
76       -h     Display a help message.
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78

LONG OPTIONS

80       Each and every configuration file option (see below) may also appear as
81       a "long" style command  line  argument.   For  example,  the  slaveOnly
82       option may be set using either of these two forms.
83
84              --slaveOnly 1   --slaveOnly=1
85
86       Option  values  given on the command line override values in the global
87       section of the configuration file.
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89

CONFIGURATION FILE

91       The configuration file is divided into sections.  Each  section  starts
92       with  a  line  containing  its name enclosed in brackets and it follows
93       with settings.  Each setting is placed on a separate line, it  contains
94       the  name  of  the option and the value separated by whitespace charac‐
95       ters. Empty lines and lines starting with # are ignored.
96
97       There are three different section types.
98
99
100       1.     The global section (indicated  as  [global])  sets  the  program
101              options,  clock options and default port options. Other sections
102              are port specific sections and they override  the  default  port
103              options.
104
105       2.     Port  sections  give  the  name  of  the  configured  port (e.g.
106              [eth0]).  Ports specified in the configuration file  don't  need
107              to  be  specified by the -i option. An empty port section can be
108              used to replace the command line option.
109
110       3.     Tables   for   configuring   unicast   discovery   begin    with
111              [unicast_master_table].
112
113              See UNICAST DISCOVERY OPTIONS, below.
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115

PORT OPTIONS

117       delayAsymmetry
118              The  time  difference in nanoseconds of the transmit and receive
119              paths. This value should be positive  when  the  master-to-slave
120              propagation time is longer and negative when the slave-to-master
121              time is longer. The default is 0 nanoseconds.
122
123       logAnnounceInterval
124              The mean time interval  between  Announce  messages.  A  shorter
125              interval  makes ptp4l react faster to the changes in the master-
126              slave hierarchy. The interval should be the same  in  the  whole
127              domain.  It's  specified  as  a  power  of  two in seconds.  The
128              default is 1 (2 seconds).
129
130       logSyncInterval
131              The mean time interval between Sync messages. A shorter interval
132              may  improve  accuracy  of  the local clock. It's specified as a
133              power of two in seconds.  The default is 0 (1 second).
134
135       operLogSyncInterval
136              The Sync message interval to be requested once the clock  enters
137              the  SERVO_LOCKED_STABLE  state.   If the 'msg_interval_request'
138              option is set, then the local slave port will request the remote
139              master  to switch to the given message rate via a signaling mes‐
140              sage containing a Message interval request TLV.  This option  is
141              specified  as  a power of two in seconds, and default value is 0
142              (1 second).
143
144       logMinDelayReqInterval
145              The minimum permitted mean time interval between Delay_Req  mes‐
146              sages.  A  shorter  interval  makes  ptp4l  react  faster to the
147              changes in the path delay. It's specified as a power of  two  in
148              seconds.  The default is 0 (1 second).
149
150       logMinPdelayReqInterval
151              The minimum permitted mean time interval between Pdelay_Req mes‐
152              sages. It's specified as a power of two in seconds.  The default
153              is 0 (1 second).
154
155       operLogPdelayReqInterval
156              The  Pdelay  Request messages interval to be used once the clock
157              enters  the  SERVO_LOCKED_STABLE  state.   If  the   'msg_inter‐
158              val_request' option is set, then the local slave port will adopt
159              this rate when the local clock enters the "locked stable" state.
160              This  option  is specified as a power of two in seconds, and the
161              default value is 0 (1 second).
162
163       inhibit_delay_req
164              Don't send any delay requests. This will need the asCapable con‐
165              fig option to be set to 'true'. This is useful when running as a
166              designated master who does not need  to  calculate  offset  from
167              slave. The default is 0 (disabled).
168
169       announceReceiptTimeout
170              The  number of missed Announce messages before the last Announce
171              messages expires.  The default is 3.
172
173       syncReceiptTimeout
174              The number of sync/follow up messages that may go missing before
175              triggering a Best Master Clock election. This option is used for
176              running in gPTP mode according  to  the  802.1AS-2011  standard.
177              Setting  this option to zero will disable the sync message time‐
178              out.  The default is 0 or disabled.
179
180       transportSpecific
181              The transport specific field. Must be in the  range  0  to  255.
182              The default is 0.
183
184       ignore_transport_specific
185              By default, incoming messages are dropped if their transportSpe‐
186              cific field does not match the configured value.  However,  many
187              of  transports  specified  in the 1588 standard mandate ignoring
188              this field.  Moreover,  some  equipment  is  known  to  set  the
189              reserved  bits.   Configuring this option as 1 causes this field
190              to be ignored completely on receive.  The default is 0.
191
192       path_trace_enabled
193              Enable the mechanism used to trace the  route  of  the  Announce
194              messages.  The default is 0 (disabled).
195
196       follow_up_info
197              Include  the  802.1AS data in the Follow_Up messages if enabled.
198              The default is 0 (disabled).
199
200       fault_reset_interval
201              The time in seconds between the detection of a port's fault  and
202              the  fault  being  reset.  This value is expressed as a power of
203              two. Setting this value to -128  or  to  the  special  key  word
204              "ASAP"  will let the fault be reset immediately.  The default is
205              4 (16 seconds).
206
207       fault_badpeernet_interval
208              The time in seconds between the detection of a peer network mis‐
209              configuration  and  the  fault being reset. The port is disabled
210              for the duration of the interval. The value is  in  seconds  and
211              the  special  key  word ASAP will let the fault be reset immedi‐
212              ately.  The default is 16 seconds.
213
214       delay_mechanism
215              Select the delay mechanism. Possible values  are  E2E,  P2P  and
216              Auto.  The default is E2E.
217
218       hybrid_e2e
219              Enables  the  "hybrid" delay mechanism from the draft Enterprise
220              Profile. When enabled, ports in the slave state send their delay
221              request  messages to the unicast address taken from the master's
222              announce message. Ports in the master state will reply  to  uni‐
223              cast  delay  requests using unicast delay responses. This option
224              has no effect if the delay_mechanism is set to P2P.  The default
225              is 0 (disabled).
226
227       inhibit_multicast_service
228              Some  unicast mode profiles insist that no multicast message are
229              ever transmitted.  Setting this option inhibits multicast trans‐
230              mission.  The default is 0 (mutlicast enabled).
231
232       net_sync_monitor
233              Enables  the  NetSync  Monitor  (NSM) protocol. The NSM protocol
234              allows a station to measure how well another  node  is  synchro‐
235              nized.  The  monitor  sends a unicast delay request to the node,
236              which replies unconditionally with unicast delay response, sync,
237              and  follow  up  messages. If the monitor is synchronized to the
238              GM, it can use the time stamps in the message  to  estimate  the
239              node's  offset.   This  option  requires  that  the 'hybrid_e2e'
240              option be enabled as well.  The default is 0 (disabled).
241
242       unicast_listen
243              When enabled, this option allows the port to grant unicast  mes‐
244              sage  contracts.   Incoming requests for will be granted limited
245              only by the amount of memory available.  The default is 0  (dis‐
246              abled).
247
248       unicast_master_table
249              When  set to a positive integer, this option specifies the table
250              id to be used for unicast discovery.  Each table  lives  in  its
251              own section and has a unique, positive numerical ID.  Entries in
252              the table are a pair of transport  type  and  protocol  address.
253              The default is 0 (unicast discovery disabled).
254
255       unicast_req_duration
256              The  service time in seconds to be requested during unicast dis‐
257              covery.  Note that the remote node is free to grant a  different
258              duration.  The default is 3600 seconds or one hour.
259
260       ptp_dst_mac
261              The  MAC address to which PTP messages should be sent.  Relevant
262              only with L2 transport. The default is 01:1B:19:00:00:00.
263
264       p2p_dst_mac
265              The MAC address to which peer delay  messages  should  be  sent.
266              Relevant    only    with    L2   transport.   The   default   is
267              01:80:C2:00:00:0E.
268
269       network_transport
270              Select the network transport. Possible values are  UDPv4,  UDPv6
271              and L2.  The default is UDPv4.
272
273       neighborPropDelayThresh
274              Upper limit for peer delay in nanoseconds. If the estimated peer
275              delay is greater than this value  the  port  is  marked  as  not
276              802.1AS capable.
277
278       masterOnly
279              Setting  this  option to one (1) prevents the port from entering
280              the SLAVE state.  In  addition,  the  local  clock  will  ignore
281              Announce  messages received on this port. This option's intended
282              use is to  support  the  Telecom  Profiles  according  to  ITU-T
283              G.8265.1,  G.8275.1,  and G.8275.2. The default value is zero or
284              false.
285
286       G.8275.portDS.localPriority
287              The Telecom Profiles (ITU-T G.8275.1 and  G.8275.2)  specify  an
288              alternate  Best Master Clock Algorithm (BMCA) with a unique data
289              set comparison algorithm.  The value of this option  is  associ‐
290              ated with Announce messages arriving on a particular port and is
291              used as a tie breaker whenever clockClass,  clockAccuracy,  off‐
292              setScaledLogVariance,  and  priority2  are equal. This option is
293              only used when "dataset_comparison" is set  to  "telecom".   The
294              default value is 128.
295
296              Warning: the BMCA is guaranteed to produce a spanning tree (that
297              is, a timing network without loops) only when using the  default
298              values        of        G.8275.defaultDS.localPriority       and
299              G.8275.portDS.localPriority.   Careful  network  engineering  is
300              needed when using non-default values.
301
302       min_neighbor_prop_delay
303              Lower limit for peer delay in nanoseconds. If the estimated peer
304              delay is smaller than this value  the  port  is  marked  as  not
305              802.1AS capable.
306
307       tsproc_mode
308              Select  the  time stamp processing mode used to calculate offset
309              and delay.  Possible  values  are  filter,  raw,  filter_weight,
310              raw_weight.  Raw  modes  perform well when the rate of sync mes‐
311              sages (logSyncInterval) is similar to the rate of delay messages
312              (logMinDelayReqInterval  or  logMinPdelayReqInterval). Weighting
313              is useful with larger network jitters (e.g. software time stamp‐
314              ing).  The default is filter.
315
316       delay_filter
317              Select  the algorithm used to filter the measured delay and peer
318              delay. Possible values  are  moving_average  and  moving_median.
319              The default is moving_median.
320
321       delay_filter_length
322              The length of the delay filter in samples.  The default is 10.
323
324       egressLatency
325              Specifies  the  difference  in  nanoseconds  between  the actual
326              transmission time at the reference plane and the reported trans‐
327              mit  time  stamp. This value will be added to egress time stamps
328              obtained from the hardware.  The default is 0.
329
330       ingressLatency
331              Specifies the difference in  nanoseconds  between  the  reported
332              receive  time  stamp  and the actual reception time at reference
333              plane. This value will be subtracted from  ingress  time  stamps
334              obtained from the hardware.  The default is 0.
335
336       boundary_clock_jbod
337              When  running  as  a boundary clock (that is, when more than one
338              network interface is configured), ptp4l performs a sanity  check
339              to make sure that all of the ports share the same hardware clock
340              device. This option allows ptp4l to work  as  a  boundary  clock
341              using  "just  a  bunch  of devices" that are not synchronized to
342              each other. For this mode, the collection of clocks must be syn‐
343              chronized  by  an  external  program,  for example phc2sys(8) in
344              "automatic" mode.  The default is 0 (disabled).
345
346       udp_ttl
347              Specifies the Time to live (TTL) value for IPv4  multicast  mes‐
348              sages and the hop limit for IPv6 multicast messages. This option
349              is only relevant with the IPv4  and  IPv6  UDP  transports.  The
350              default  is 1 to restrict the messages sent by ptp4l to the same
351              subnet.
352
353

PROGRAM AND CLOCK OPTIONS

355       twoStepFlag
356              Enable two-step mode for sync messages.  One-step  mode  can  be
357              used  only  with  hardware  time  stamping.   The  default  is 1
358              (enabled).
359
360       slaveOnly
361              The local clock is a slave-only clock if enabled. The default is
362              0 (disabled).
363
364       socket_priority
365              Configure  the  SO_PRIORITY of sockets. This is to support cases
366              where a user wants to route ptp4l traffic using Linux qdiscs for
367              the  purpose  of  traffic shaping. This option is only available
368              with the IEEE 802.3 transport (the -2 option)  and  is  silently
369              ignored when using the UDP IPv4/6 network transports. Must be in
370              the range of 0 to 15, inclusive. The default is 0.
371
372       gmCapable
373              If this option is enabled, then  the  local  clock  is  able  to
374              become  grand  master.  This is only for use with 802.1AS clocks
375              and has no effect on 1588 clocks.  The default is 1 (enabled).
376
377       priority1
378              The priority1 attribute of the local clock. It is  used  in  the
379              best  master  selection algorithm, lower values take precedence.
380              Must be in the range 0 to 255.  The default is 128.
381
382       priority2
383              The priority2 attribute of the local clock. It is  used  in  the
384              best  master  selection algorithm, lower values take precedence.
385              Must be in the range 0 to 255.  The default is 128.
386
387       clockClass
388              The clockClass attribute of the  local  clock.  It  denotes  the
389              traceability  of  the time distributed by the grandmaster clock.
390              The default is 248.
391
392       clockAccuracy
393              The clockAccuracy attribute of the local clock. It  is  used  in
394              the best master selection algorithm.  The default is 0xFE.
395
396       clockIdentity
397              The  clockIdentity attribute of the local clock.  The clockIden‐
398              tity is an 8-octet array and should  in  this  configuration  be
399              written  in textual form, see default. It should be unique since
400              it is used to identify the specific clock.  If default  is  used
401              or  if  not  set  at all, the clockIdentity will be automtically
402              generated.  The default is "000000.0000.000000"
403
404       offsetScaledLogVariance
405              The offsetScaledLogVariance attribute of  the  local  clock.  It
406              characterizes  the  stability  of  the  clock.   The  default is
407              0xFFFF.
408
409       G.8275.defaultDS.localPriority
410              The Telecom Profiles (ITU-T G.8275.1 and  G.8275.2)  specify  an
411              alternate  Best Master Clock Algorithm (BMCA) with a unique data
412              set comparison algorithm.  The value of this option  is  associ‐
413              ated  with the local clock and is used as a tie breaker whenever
414              clockClass, clockAccuracy, offsetScaledLogVariance,  and  prior‐
415              ity2  are equal. This option is only used when "dataset_compari‐
416              son" is set to "telecom".  The default value is 128.
417
418              Warning: the BMCA is guaranteed to produce a spanning tree (that
419              is,  a timing network without loops) only when using the default
420              values       of        G.8275.defaultDS.localPriority        and
421              G.8275.portDS.localPriority.   Careful  network  engineering  is
422              needed when using non-default values.
423
424       maxStepsRemoved
425              When using this option, if  the  value  of  stepsRemoved  of  an
426              Announce  message  is  greater  than  or  equal  to the value of
427              maxStepsRemoved the Announce message is not  considered  in  the
428              operation of the BMCA.  The default value is 255.
429
430
431       domainNumber
432              The domain attribute of the local clock.  The default is 0.
433
434       utc_offset
435              The current offset between TAI and UTC.  The default is 37.
436
437       free_running
438              Don't adjust the local clock if enabled.  The default is 0 (dis‐
439              abled).
440
441       freq_est_interval
442              The time interval over which is estimated the ratio of the local
443              and peer clock frequencies. It is specified as a power of two in
444              seconds.  The default is 1 (2 seconds).
445
446       assume_two_step
447              Treat one-step responses as two-step if enabled. It is  used  to
448              work  around  buggy  802.1AS  switches.   The default is 0 (dis‐
449              abled).
450
451       tc_spanning_tree
452              When running as a Transparent  Clock,  increment  the  "stepsRe‐
453              moved"  field of Announce messages that pass through the switch.
454              Enabling this option ensures that PTP message loops never  form,
455              provided  the  switches  all implement this option together with
456              the BMCA.
457
458       tx_timestamp_timeout
459              The number of milliseconds to poll waiting for the tx time stamp
460              from  the  kernel  when  a  message has recently been sent.  The
461              default is 1.
462
463       check_fup_sync
464              Because of packet reordering that can occur in the  network,  in
465              the  hardware,  or  in the networking stack, a follow up message
466              can appear to arrive in the application before the matching sync
467              message. As this is a normal occurrence, and the sequenceID mes‐
468              sage field ensures proper matching, the  ptp4l  program  accepts
469              out of order packets. This option adds an additional check using
470              the software time stamps from the  networking  stack  to  verify
471              that the sync message did arrive first. This option is only use‐
472              ful if you do not trust the sequence IDs generated by  the  mas‐
473              ter.  The default is 0 (disabled).
474
475       clock_servo
476              The  servo  which  is used to synchronize the local clock. Valid
477              values are "pi" for a PI controller, "linreg"  for  an  adaptive
478              controller  using  linear  regression,  "ntpshm" for the NTP SHM
479              reference clock to allow  another  process  to  synchronize  the
480              local  clock  (the  SHM segment number is set to the domain num‐
481              ber), and "nullf" for a servo that always dials frequency offset
482              zero (for use in SyncE nodes).  The default is "pi."
483
484       clock_type
485              Specifies  the  kind  of  PTP  clock.  Valid values are "OC" for
486              ordinary clock, "BC" for boundary clock, "P2P_TC"  for  peer  to
487              peer  transparent clock, and "E2E_TC" for end to end transparent
488              clock.  An multi-port ordinary clock will automatically be  con‐
489              figured as a boundary clock.  The default is "OC".
490
491       pi_proportional_const
492              The proportional constant of the PI controller. When set to 0.0,
493              the proportional constant will be set by the  following  formula
494              from the current sync interval.  The default is 0.0.
495
496              kp = min(kp_scale * sync^kp_exponent, kp_norm_max / sync)
497
498       pi_integral_const
499              The integral constant of the PI controller. When set to 0.0, the
500              integral constant will be set by the following formula from  the
501              current sync interval.  The default is 0.0.
502
503              ki = min(ki_scale * sync^ki_exponent, ki_norm_max / sync)
504
505       pi_proportional_scale
506              The  kp_scale  constant  in  the formula used to set the propor‐
507              tional constant of the PI controller  from  the  sync  interval.
508              When set to 0.0, the value will be selected from 0.7 and 0.1 for
509              the hardware  and  software  time  stamping  respectively.   The
510              default is 0.0.
511
512       pi_proportional_exponent
513              The  kp_exponent constant in the formula used to set the propor‐
514              tional constant of the PI controller  from  the  sync  interval.
515              The default is -0.3.
516
517       pi_proportional_norm_max
518              The  kp_norm_max constant in the formula used to set the propor‐
519              tional constant of the PI controller  from  the  sync  interval.
520              The default is 0.7
521
522       pi_integral_scale
523              The  ki_scale  constant  in the formula used to set the integral
524              constant of the PI controller from the sync interval.  When  set
525              to  0.0,  the  value will be selected from 0.3 and 0.001 for the
526              hardware and software time stamping respectively.   The  default
527              is 0.0.
528
529       pi_integral_exponent
530              The ki_exponent constant in the formula used to set the integral
531              constant of the PI  controller  from  the  sync  interval.   The
532              default is 0.4.
533
534       pi_integral_norm_max
535              The ki_norm_max constant in the formula used to set the integral
536              constant of the PI  controller  from  the  sync  interval.   The
537              default is 0.3.
538
539       step_threshold
540              The  maximum offset the servo will correct by changing the clock
541              frequency instead of stepping the clock. When set  to  0.0,  the
542              servo  will never step the clock except on start. It's specified
543              in seconds.  The default is 0.0.  This option used to be  called
544              pi_offset_const.
545
546       first_step_threshold
547              The  maximum offset the servo will correct by changing the clock
548              frequency instead of stepping the clock. This is only applied on
549              the  first  update.  It's specified in seconds. When set to 0.0,
550              the servo won't step the clock on start.  The default is 0.00002
551              (20  microseconds).   This  option  used  to be called pi_f_off‐
552              set_const.
553
554       max_frequency
555              The maximum allowed frequency adjustment of the clock  in  parts
556              per  billion  (ppb).  This is an additional limit to the maximum
557              allowed by the hardware. When set to 0, the hardware limit  will
558              be  used.   The default is 900000000 (90%).  This option used to
559              be called pi_max_frequency.
560
561       sanity_freq_limit
562              The maximum allowed frequency offset between  uncorrected  clock
563              and  the system monotonic clock in parts per billion (ppb). This
564              is used as a sanity check of  the  synchronized  clock.  When  a
565              larger offset is measured, a warning message will be printed and
566              the servo will be reset. When set to 0, the sanity check is dis‐
567              abled. The default is 200000000 (20%).
568
569       initial_delay
570              The initial path delay of the clock in nanoseconds used for syn‐
571              chronization of the clock before the delay is measured using the
572              E2E  or  P2P delay mechanism. If set to 0, the clock will not be
573              updated until the delay is measured.  The default is 0.
574
575       ntpshm_segment
576              The number of the SHM segment used by ntpshm servo.  The default
577              is 0.
578
579       udp6_scope
580              Specifies  the  desired  scope  for the IPv6 multicast messages.
581              This will be used as the second byte  of  the  primary  address.
582              This option is only relevant with IPv6 transport.  See RFC 4291.
583              The default is 0x0E for the global scope.
584
585       uds_address
586              Specifies the address of the UNIX domain  socket  for  receiving
587              local management messages. The default is /var/run/ptp4l.
588
589       dscp_event
590              Defines  the Differentiated Services Codepoint (DSCP) to be used
591              for PTP event messages. Must be a value between 0 and 63.  There
592              are  several  media  streaming  standards out there that require
593              specific values for this option.  For example  46  (EF  PHB)  in
594              AES67 or 48 (CS6 PHB) in RAVENNA. The default is 0.
595
596       dscp_general
597              Defines  the Differentiated Services Codepoint (DSCP) to be used
598              for PTP general messages. Must be a  value  between  0  and  63.
599              There  are several media streaming standards out there that rec‐
600              ommend specific values for this option.  For  example  34  (AF41
601              PHB) in AES67 or 46 (EF PHB) in RAVENNA. The default is 0.
602
603       dataset_comparison
604              Specifies  the method to be used when comparing data sets during
605              the Best  Master  Clock  Algorithm.   The  possible  values  are
606              "ieee1588" and "G.8275.x".  The default is "ieee1588".
607
608       logging_level
609              The  maximum  logging level of messages which should be printed.
610              The default is 6 (LOG_INFO).
611
612       message_tag
613              The tag which is added to all messages printed to  the  standard
614              output  or  system  log.   The default is an empty string (which
615              cannot be set in the configuration file as the  option  requires
616              an argument).
617
618       verbose
619              Print  messages  to the standard output if enabled.  The default
620              is 0 (disabled).
621
622       use_syslog
623              Print messages to the system log if enabled.  The default  is  1
624              (enabled).
625
626       summary_interval
627              The time interval in which are printed summary statistics of the
628              clock. It is specified as a power of two in seconds. The statis‐
629              tics  include  offset  root  mean square (RMS), maximum absolute
630              offset, frequency offset mean and standard deviation,  and  path
631              delay mean and standard deviation. The units are nanoseconds and
632              parts per billion (ppb). If there is only one  clock  update  in
633              the  interval, the sample will be printed instead of the statis‐
634              tics. The messages are  printed  at  the  LOG_INFO  level.   The
635              default is 0 (1 second).
636
637       time_stamping
638              The time stamping method. The allowed values are hardware, soft‐
639              ware and legacy.  The default is hardware.
640
641       productDescription
642              The product description string. Allowed values must  be  of  the
643              form manufacturerName;modelNumber;instanceIdentifier and contain
644              at most 64 utf8 symbols. The default is ";;".
645
646       revisionData
647              The revision description string which contains the revisions for
648              node  hardware  (HW),  firmware (FW), and software (SW). Allowed
649              values are of the form HW;FW;SW and contain at most 32 utf8 sym‐
650              bols. The default is an ";;".
651
652       userDescription
653              The  user  description  string.  Allowed  values are of the form
654              name;location and contain at most 128 utf8 symbols. The  default
655              is an empty string.
656
657       manufacturerIdentity
658              The manufacturer id which should be an OUI owned by the manufac‐
659              turer.  The default is 00:00:00.
660
661       kernel_leap
662              When a leap second is announced, let  the  kernel  apply  it  by
663              stepping  the  clock instead of correcting the one-second offset
664              with servo, which would correct the one-second offset slowly  by
665              changing  the  clock frequency (unless the step_threshold option
666              is set to correct such offset by stepping).  Relevant only  with
667              software time stamping. The default is 1 (enabled).
668
669       timeSource
670              The  time source is a single byte code that gives an idea of the
671              kind of local clock in use. The value is  purely  informational,
672              having  no  effect on the outcome of the Best Master Clock algo‐
673              rithm, and is advertised when the clock becomes grand master.
674
675       hwts_filter
676              Select the hardware time stamp filter  setting  mode.   Possible
677              values  are normal, check, full.  Normal mode set the filters as
678              needed.  Check mode only check but do not set.   Full  mode  set
679              the receive filter to mark all packets with hardware time stamp,
680               so all applications can get them.  The default is normal.
681
682       asCapable
683              If set to 'true', all the checks which can unset asCapable vari‐
684              able (as described in Section 10.2.4.1 of 802.1AS) are  skipped.
685              If  set  to 'auto', asCapable is initialized to 'false' and will
686              be set to 'true' after the  relevant  checks  have  passed.  The
687              default value is 'auto'.
688
689       BMCA   This  option  enables  use  of static roles for master and slave
690              devices instead of  running  the  best  master  clock  algorithm
691              (BMCA)  described  in 1588 profile. This is useful when you know
692              the roles of the devices in advance. When  set  to  ´noop',  the
693              traditional  BMCA  algorithm used by 1588 is skipped. masterOnly
694              and slaveOnly will be used to determine master or slave role for
695              the  device.  In  a bridge, slaveOnly (which is a global option)
696              can be set to make all ports assume the slave  role.  masterOnly
697              (which  is  a  per-port  config  option) can then be used to set
698              individual ports to take master role. BMCA is used in the  Auto‐
699              motive  profile  to speed up the start time for grand master and
700              slaves. The default value is 'ptp' which runs the  BMCA  related
701              state machines.
702
703       inhibit_announce
704              This   will  disable  the  timer  for  announce  messages  (i.e.
705              FD_MANNO_TIMER) and also  the  announce  message  timeout  timer
706              (i.e. FD_ANNOUNCE_TIMER). This is used by the Automotive profile
707              as part of switching over to a static BMCA. if  this  option  is
708              enabled, ignore_source_id has to be enabled in the slave because
709              it has no way to identify master identity in Sync and  Follow_Up
710              messages. The default is 0 (disabled).
711
712       ignore_source_id
713              This  will  disable  source  port identity checking for Sync and
714              Follow_Up messages. This is useful when  the  announce  messages
715              are  disabled  in the master and the slave does not have any way
716              to know it's identity. The default is 0 (disabled).
717
718       msg_interval_request
719              This option, when set, will trigger an adjustment  to  the  Sync
720              and  peer  delay  request message intervals when the clock servo
721              transitions into the SERVO_LOCKED_STABLE state.  The Sync inter‐
722              val  will be adjusted via the signaling mechanism while the pde‐
723              lay request interval is simply adjusted locally.  The values  to
724              use for the new Sync and peer delay request intervals are speci‐
725              fied by  the  operLogSyncInterval  and  operLogPdelayReqInterval
726              options,   respectively.    The   default  value  of  msg_inter‐
727              val_request is 0 (disabled).
728
729       servo_num_offset_values
730              The number of offset values considered in  order  to  transition
731              from  the  SERVO_LOCKED  to  the SERVO_LOCKED_STABLE state.  The
732              transition occurs once the last  'servo_num_offset_values'  off‐
733              sets  are  all  below  the  'servo_offset_threshold' value.  The
734              default value is 10.
735
736       servo_offset_threshold
737              The offset threshold  used  in  order  to  transition  from  the
738              SERVO_LOCKED  to  the SERVO_LOCKED_STABLE state.  The transition
739              occurs once the last The default value of offset_threshold is  0
740              (disabled).
741
742       slave_event_monitor
743              Specifies  the  address  of a UNIX domain socket for slave event
744              monitoring.  A local client bound to this address  will  receive
745              SLAVE_RX_SYNC_TIMING_DATA  and  SLAVE_DELAY_TIMING_DATA_NP TLVs.
746              The default is the empty string (disabled).
747
748       write_phase_mode
749              This option enables using the "write phase"  feature  of  a  PTP
750              Hardware  Clock.  If supported by the device, this mode uses the
751              hardware's built in phase offset control  instead  of  frequency
752              offset control.  The default value is 0 (disabled).
753
754

UNICAST DISCOVERY OPTIONS

756       table_id
757              Each  table  must  begin  with a unique, positive table ID.  The
758              port that claims a given table does so by including  the  ID  as
759              the value of its 'unicast_master_table' option.
760
761       logQueryInterval
762              This option configures the time to wait between unicast negotia‐
763              tion attempts.  It is specified as a power of  two  in  seconds.
764              The default is 0 (1 second).
765
766       peer_address
767              This  option  specifies  the unicast address of the peer for use
768              with the peer to peer delay mechanism.  If specified,  the  port
769              owning  the  table  will  negotiate unicast peer delay responses
770              from the machine at the given remote address, otherwise the port
771              will send multicast peer delay requests.
772
773       L2|UDPv4|UDPv6
774              Each  table  entry  specifies  the  transport  type  and network
775              address of a potential remote master.  If multiple  masters  are
776              specified,  then unicast negotiation will be performed with each
777              if them.
778
779

TIME SCALE USAGE

781       ptp4l as domain master either uses PTP or UTC time scale  depending  on
782       time  stamping  mode.   In  software  and legacy time stamping modes it
783       announces Arbitrary time scale mode, which is effectively UTC here,  in
784       hardware time stamping mode it announces use of PTP time scale.
785
786       When  ptp4l is the domain master using hardware time stamping, it is up
787       to phc2sys to maintain the correct offset between UTC  and  PTP  times.
788       See phc2sys(8) manual page for more details.
789
790

SEE ALSO

792       pmc(8), phc2sys(8)
793
794
795
796linuxptp                          April 2018                          PTP4l(8)
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