syncstat(1M)						  System Administration Commands					      syncstat(1M)

NAME

       syncstat - report driver statistics from a synchronous serial link

SYNOPSIS

       /usr/sbin/syncstat [-c] device [interval]

DESCRIPTION

       The  syncstat command reports the event statistics maintained by a synchronous serial device driver. The report may be a single snapshot of
       the accumulated totals, or a series of samples showing incremental changes. Prior to these it prints the device name being used to query  a
       particular device driver, along with a number indicating the channel number (ppa) under control of that driver.

       Event statistics are maintained by a driver for each physical channel that it supports. They are initialized to zero at the time the driver
       module is loaded into the system, which may be either at boot time or when one of the driver's entry points is first called.

       The  device argument is the name of the serial device as it appears in the /dev directory.  For example,  zsh0 specifies the first on-board
       serial device.

       The following is a breakdown of	syncstat output:

       speed	     The  line	speed  the device has been set to
		     operate at. It is the user's  responsibility
		     to  make  this value correspond to the modem
		     clocking speed when clocking is provided  by
		     the modem.
       ipkts	     The total number of input packets.
       opkts	     The total number of output packets.
       undrun	     The number of transmitter underrun errors.
       ovrrun	     The number of receiver overrun errors.
       abort	     The number of aborted received frames.
       crc	     The  number  of  received	frames	with  CRC
		     errors.
       isize	     The average size (in bytes) of  input  pack-
		     ets.
       osize	     The  average size (in bytes) of output pack-
		     ets.

OPTIONS

       -c	       Clear the accumulated statistics for the device specified. This may be useful when it is not desirable to unload a particu-
		       lar driver, or when the driver is not capable of being unloaded.

       interval        syncstat  samples  the statistics every	interval seconds and reports incremental changes. The output reports line utiliza-
		       tion for input and output in place of average packet sizes.  These are the relationships between bytes transferred and  the
		       baud  rate,  expressed  as percentages. The loop repeats indefinitely, with a column heading printed every twenty lines for
		       convenience.

EXAMPLES

       Example 1: Sample output from the syncstat command:

       example# syncstat zsh0
       speed ipkts opkts undrun ovrrun abort crc isize osize
       9600  15716 17121   0	  0	 1    3   98	89

       example# syncstat -c zsh0
       speed ipkts opkts undrun ovrrun abort crc isize osize
       9600   0     0	  0	 0	0     0    0	 0

       In the following sample output a new line of output is generated every five seconds:

       example# syncstat zsh0 5
       ipkts opkts undrun ovrrun abort crc iutil outil
       12    10      0	   0	  0	0   5%	  4%
       22    60      0	   0	  0	0   3%	  90%
       36    14      0	   0	  0	1   51%   2%

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       syncinit(1M), syncloop(1M), attributes(5), zsh(7D)

DIAGNOSTICS

       bad interval: arg		       The argument  arg is expected to be an interval and could not be understood.

       device missing minor device number      The name  device does not end in a decimal number that can be used as a minor device number.

       baud rate not set		       The  interval option is being used and the baud rate on the device is  zero.  This  would  cause  a
					       divide-by-zero error when computing the line utilization statistics.

WARNINGS

       Underrun,  overrun,  frame-abort, and CRC errors have a variety of causes. Communication protocols are typically able to handle such errors
       and initiate recovery of the transmission in which the error occurred. Small numbers of such errors are not a significant problem for  most
       protocols.  However,  because the overhead involved in recovering from a link error can be much greater than that of normal operation, high
       error rates can greatly degrade overall link throughput. High error rates are often caused by  problems	in  the  link  hardware,  such	as
       cables, connectors, interface electronics or telephone lines. They may also be related to excessive load on the link or the supporting sys-
       tem.

       The percentages for input and output line utilization reported when using the  interval option may occasionally	be  reported  as  slightly
       greater	than  100%  because of inexact sampling times and differences in the accuracy between the system clock and the modem clock. If the
       percentage of use greatly exceeds 100%, or never exceeds 50%, then the baud rate set for the device probably does not reflect the speed	of
       the modem.

SunOS 5.10							    9 Mar 1993							      syncstat(1M)