NAME

nettrstart − enable network tracing

SYNOPSIS

/usr/bin/nettrstart [ -trl ] [ -b buffersize ] [ -m maxsize ] [ -f filename | -]
[ -Ssubsystem:qualifier_name=qualifier]
 
 
or
 
/usr/bin/nettrstart -s

DESCRIPTION

Network tracing will record Ethernet and IEEE 802.3 messages at the link level as they enter or leave a node.  In addition, network tracing can record IP loopback packets. 

Nettrstart stores trace packets as binary data.  Nettrfmt converts the binary data into more readable form.  Nettrstart can be executed only by a super-user. 

The nettrstart options are:

-s Shows the status of link-level tracing on your node.  The -s option cannot be used with other nettrstart options. 

-t Trace Ethernet and IEEE 802.3 packets transmitted by the node. 

-r Trace Ethernet and IEEE 802.3 packets received by the node. 

-tr (Default) Trace Ethernet and IEEE 802.3 packets transmitted and received by the node. 

-l Trace local loopback packets. 

−b buffer_size Size of the tracing kernel buffer, in bytes.  The kernel buffer is circular. If necessary, a full buffer will drop the oldest message received to make room for a new incoming message.  Range: 2 Kilobytes to 4,000 Kilobytes.  Default: 32 Kilobytes. 

−m maxsize Maximum number of bytes traced per packet.  Packets larger than maxsize are truncated to maxsize.  Range: 14 bytes to 2,000 bytes.  Default: Entire packet is traced. 

−f filename Packets are traced to the file filename. 

-f - Packets are traced to standard output.  The tracing process runs in the foreground. 

-Ssubsystem:qualifier_name=qualifier
Specifies the subsystem to be traced (subsystem), and any qualifier acting as a filter for events on that subsystem.  The only supported subsystem is link, the only qualifier_name supported is interface.  The only qualifier values supported are network interfaces, such as lan0, lan1, or lan2.  Interface filtering differs from formatter filtering described in nettrfmt(1M).  Interface filtering occurs at run time as packets are traced.  Formatter filtering occurs after packets are traced.  Interface filtering uses the tracing facility more efficiently by tracing only packets for a selected network interface. 

DIAGNOSTICS

Messages indicate incorrect usage, the network tracing has already been started, file could not be opened, illegal maximum trace size specified, illegal buffer size specified, or the user is not privileged. 

WARNINGS

Tracing to a file is slow and cannot keep up with a busy network: data will be dropped (not traced). 

DEPENDENCIES

Implemented on the Series 300 and 800 only. 

AUTHOR

HP

FILES

/dev/nsdiag1 NS diagnostics multiple access device file used for ioctl()’s.

SEE ALSO

nettrstop(1M), nettrdump(1M), nettrfmt(1M). 
 

Hewlett-Packard Company  —  May 11, 2021