mtr

MTR(8)				     mtr			       MTR(8)



NAME
       mtr - a network diagnostic tool



SYNOPSIS
       mtr	 [-hvrctglsni]	    [--help]	  [--version]	   [--report]
       [--report-cycles COUNT]	[--curses]   [--split]	 [--raw]   [--no-dns]
       [--gtk] [--address IP.ADD.RE.SS] [--interval SECONDS] [--psize BYTES |
       -p BYTES] HOSTNAME [PACKETSIZE]



DESCRIPTION
       mtr combines the functionality of the traceroute and ping programs  in
       a single network diagnostic tool.


       As mtr starts, it investigates the network connection between the host
       mtr runs on and HOSTNAME.  by sending packets with purposly low	TTLs.
       It continues to send packets with low TTL, noting the response time of
       the intervening routers.	 This allows mtr to print the  response	 per-
       centage	and response times of the internet route to HOSTNAME.  A sud-
       den increase in packetloss or response time is often an indication  of
       a bad (or simply overloaded) link.


OPTIONS
       -h

       --help
	      Print the summary of command line argument options.


       -v

       --version
	      Print the installed version of mtr.


       -r

       --report
	      This  option puts mtr into report mode.  When in this mode, mtr
	      will run for the number of cycles specified by the  -c  option,
	      and then print statistics and exit.

	      This  mode  is  useful  for generating statistics about network
	      quality.	Note that each running instance of  mtr	 generates  a
	      significant  amount  of  network traffic.	 Using mtr to measure
	      the quality of your network may  result  in  decreased  network
	      performance.


       -c COUNT

       --report-cycles COUNT
	      Use  this	 option	 to set the number of pings sent to determine
	      both the machines on the network and the reliability  of	those
	      machines.	  Each	cycle  lasts one second.  This option is only
	      useful with the -r option.


       -p BYTES

       --psize BYTES

       PACKETSIZE
	      These options or a trailing PACKETSIZE on the commandline	 sets
	      the  packet size used for probing.  It is in bytes inclusive IP
	      and ICMP headers

       -t

       --curses
	      Use this option to force mtr to use the curses  based  terminal
	      interface (if available).


       -n

       --no-dns
	      Use  this option to force mtr to display numeric IP numbers and
	      not try to resolve the host names.


       -g

       --gtk
	      Use this option to force mtr to use the GTK+ based  X11  window
	      interface (if available).	 GTK+ must have been available on the
	      system when mtr was built for this to work.  See the  GTK+  web
	      page  at	http://www.gimp.org/gtk/  for  more information about
	      GTK+.


       -s

       --split
	      Use this option to set mtr to spit out a format that  is	suit-
	      able for a split-user interface.


       -l

       --raw
	      Use  this option to tell mtr to use the raw output format. This
	      format  is  better  suited  for  archival	 of  the  measurement
	      results.	It  could  be  parsed to be presented into any of the
	      other display methods.


       -a IP.ADD.RE.SS

       --address IP.ADD.RE.SS
	      Use this option to bind outgoing packets’	 socket	 to  specific
	      interface,  so that any packet will be sent through this inter-
	      face. NOTE that this  option  doesn’t  apply  to	DNS  requests
	      (which could be and could not be what you want).


       -i SECONDS

       --interval SECONDS
	      Use  this	 option	 to  specify  the  positive number of seconds
	      between ICMP ECHO requests.  The default value for this parame-
	      ter is one second.


BUGS
       Some modern routers give a lower priority to ICMP ECHO packets than to
       other network traffic.  Consequently, the reliability of these routers
       reported	 by mtr will be significantly lower than the actual reliabil-
       ity of these routers.



CONTACT INFORMATION
       For the latest version, see the mtr  web	 page  at  http://www.bitwiz-
       ard.nl/mtr/.


       Subscribe  to the mtr mailing list.  All mtr related announcements are
       posted to the mtr mailing list.	To subscribe, send  email  to  major-
       domo@lists.xmission.com with subscribe mtr in the body of the message.
       To send a message to the mailing list, mail to mtr@lists.xmission.com.


       Bug  reports  and  feature  requests should be sent to the mtr mailing
       list.



SEE ALSO
       traceroute(8), ping(8).



mtr				March 4, 1999			       MTR(8)