| .TH NSM 8 "March 2024" "linuxptp" |
| .SH NAME |
| nsm \- NetSync Monitor client |
| |
| .SH SYNOPSIS |
| .B nsm |
| [ |
| .BI \-f " config" |
| ] [ |
| .BI \-i " interface" |
| ] [ |
| .I long-options |
| ] [ command ] ... |
| |
| .SH DESCRIPTION |
| .B nsm |
| is a program which implements a NetSync Monitor (NSM) client. NSM is an |
| extension to the Precision Time Protocol (PTP), which enables a client to |
| measure the offset of its clock against any PTP clock in the network which |
| supports NSM. It uses unicast messages, but unlike PTP in the unicast mode it |
| does not require the server to keep any state specific to the client. It is |
| particularly useful for monitoring. |
| |
| The program reads commands from the standard input or from the command line. |
| |
| .SH COMMANDS |
| |
| .TP |
| .BI NSM " address" |
| Send a NetSync Monitor request to the specified network address (IPv4 or MAC) |
| and print the measured offset with the response. |
| .TP |
| .B help |
| Display a help message. |
| |
| .SH OPTIONS |
| |
| .TP |
| .BI \-f " config" |
| Read configuration from the specified file. No configuration file is read by |
| default. |
| .TP |
| .BI \-i " interface" |
| Specify the network interface. |
| .TP |
| .B \-h |
| Display a help message. |
| .TP |
| .B \-v |
| Print the software version and exit. |
| |
| .SH LONG OPTIONS |
| |
| Each and every configuration file option (see below in sections |
| .BR PROGRAM\ OPTIONS |
| and |
| .BR PORT\ OPTIONS ) |
| may also appear |
| as a "long" style command line argument. For example, the transportSpecific |
| option may be set using either of these two forms: |
| |
| .RS |
| \f(CW\-\-transportSpecific 1 \-\-transportSpecific=1\fP |
| .RE |
| |
| Option values given on the command line override values in the global |
| section of the configuration file (which, in turn, overrides default |
| values). |
| |
| .SH CONFIGURATION FILE |
| |
| The configuration file is divided into sections. Each section starts with a |
| line containing its name enclosed in brackets and it follows with settings. |
| Each setting is placed on a separate line, it contains the name of the |
| option and the value separated by whitespace characters. Empty lines and lines |
| starting with # are ignored. |
| |
| The global section (indicated as |
| .BR [global] ) |
| sets the global program options as well as the default port specific options. |
| Other sections are port specific sections and they override the default port |
| options. The name of the section is the name of the configured port (e.g. |
| .BR [eth0] |
| ). |
| |
| .SH PORT OPTIONS |
| .TP |
| .B active_key_id |
| Used in conjunction with \fBspp\fR and \fBsa_file\fR directives to |
| specify which key from the \fBspp\fR defined Security Association |
| should be used for outbound icv calculations. All Security Assocations |
| are read from the file specified by \fBsa_file\fR. Requires \fBspp\fR |
| and \fBsa_file\fR directives. Must be in the range of 1 to 2^32-1, |
| inclusive. The default is 0 (disabled). |
| .TP |
| .B delayAsymmetry |
| The time difference in nanoseconds of the transmit and receive |
| paths. This value should be positive when the master-to-slave |
| propagation time is longer and negative when the slave-to-master time |
| is longer. The default is 0 nanoseconds. |
| .TP |
| .B network_transport |
| Select the network transport. Possible values are UDPv4 and L2. The default |
| is UDPv4. |
| .TP |
| .B spp |
| Specifies the Security Parameters Pointer of the desired Security |
| Association to be used for Authentication TLV support for a given port. |
| Any port with an assigned spp will attach Authentication TLVs to all |
| outbound messages and check for Authentication TLVs on all inbound |
| messages in accordance to the corresponding security association |
| sourced via the \fBsa_file\fR directive. Outbound Authentication TLVs |
| are generated using the key specified by \fBactive_key_id\fR. Not |
| compatible with one step ports or advertised versions less then |
| PTPv2.1. Requires \fBsa_file\fR and \fBactive_key_id\fR directives. |
| Must be in the range of 0 to 255, inclusive. |
| The default is -1 (disabled). |
| .TP |
| .B transportSpecific |
| The transport specific field. Must be in the range 0 to 255. |
| The default is 0. |
| |
| .SH PROGRAM OPTIONS |
| |
| .TP |
| .B domainNumber |
| The domain attribute of the local clock. The default is 0. |
| .TP |
| .B sa_file |
| Specifies the location of the file containing Security Associations |
| used for immediate security processing of the Authentication TLV in |
| support of the optional security mechanism defined in ieee1588-2019 |
| ch 14.16. See \fBSECURITY ASSOCIATION OPTIONS\fR for information on how |
| this file should be formatted. \fBspp\fR and \fBactive_key_id\fR should |
| be specifed for each port to indicate which Security Association from |
| the /fBsa_file/fR should be used. The default is an empty string. |
| .TP |
| .B time_stamping |
| The time stamping method. The allowed values are hardware, software and legacy. |
| The default is hardware. |
| |
| .SH WARNING |
| |
| Be cautious when the same configuration file is used for both ptp4l |
| and nsm. Keep in mind that values specified in the configuration file |
| take precedence over their default values. If a certain option which |
| is common to ptp4l and nsm is specified to a non-default value in the |
| configuration file (e.g. for ptp4l), then this non-default value |
| applies also for nsm. This might be not what is expected. |
| |
| To avoid securely these unexpected behaviour, different configuration files |
| for ptp4l and nsm are recommended. |
| |
| .SH SEE ALSO |
| .BR ptp4l (8) |
