MTR(8)			     System Administration			MTR(8)



NAME
       mtr - a network diagnostic tool

SYNOPSIS
       mtr  [-4|-6]  [-F FILENAME]  [--report] [--report-wide] [--xml] [--gtk]
       [--curses]  [--displaymode MODE]	 [--raw]  [--csv]  [--json]  [--split]
       [--no-dns] [--show-ips] [-o FIELDS] [-y IPINFO] [--aslookup] [-i INTER-
       VAL]  [-c COUNT]	  [-s PACKETSIZE]   [-B BITPATTERN]   [-G GRACEPERIOD]
       [-Q TOS]	    [--mpls]	[-a ADDRESS]	[-f FIRST-TTL]	  [-m MAX-TTL]
       [-U MAX-UNKNOWN]	 [--udp]  [--tcp]  [--sctp]  [-P PORT]	[-L LOCALPORT]
       [-Z TIMEOUT] [-M MARK] HOSTNAME

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 purposely 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 sudden
       increase	 in  packet  loss or response time is often an indication of a
       bad (or simply overloaded) link.

       The results are usually reported as round-trip-response times  in  mil-
       liseconds and the percentage of packetloss.

OPTIONS
       -h, --help
	      Print the summary of command line argument options.

       -v, --version
	      Print the installed version of mtr.

       -4     Use IPv4 only.

       -6     Use IPv6 only.  (IPV4 may be used for DNS lookups.)

       -F FILENAME, --filename FILENAME
	      Reads the list of hostnames from the specified file.

       -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  perfor-
	      mance.

       -w, --report-wide
	      This  option puts mtr into wide report mode.  When in this mode,
	      mtr will not cut hostnames in the report.

       -x, --xml
	      Use this option to tell mtr to use the xml output format.	  This
	      format is better suited for automated processing of the measure-
	      ment results.

       -t, --curses
	      Use this option to force mtr to use the  curses  based  terminal
	      interface	 (if available).  In case the list of hops exceeds the
	      height of your terminal, you can use the + and - keys to	scroll
	      up and down half a page.

	      Ctrl-L  clears  spurious error messages that may overwrite other
	      parts of the display.


       --displaymode MODE
	      Use this option to select the initial display mode: 0  (default)
	      selects  statistics,  1  selects	the stripchart without latency
	      information, and 2 selects the stripchart with latency  informa-
	      tion.

       -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.gtk.org/> for more information about GTK+.

       -l, --raw
	      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.

	      Example of the raw output format:
	      h 0 10.1.1.1
	      p 0 339
	      h 1 46.149.16.4
	      p 1 530
	      h 2 172.31.1.16
	      p 2 531
	      h 3 82.221.168.236
	      p 3 1523
	      h 5 195.130.211.8
	      p 5 1603
	      h 6 193.4.58.17
	      p 6 1127
	      h 7 193.4.58.17
	      d 7 www.isnic.is

       -C, --csv
	      Use the Comma-Separated-Value (CSV) output format.   (Note:  The
	      separator is actually a semi-colon ';'.)

	      Example of the CSV output format:
	      MTR.0.86+git:16e39fc0;1435562787;OK;nic.is;1;r-76520-PROD.greenqloud.internal;288
	      MTR.0.86+git:16e39fc0;1435562787;OK;nic.is;2;46.149.16.4;2086
	      MTR.0.86+git:16e39fc0;1435562787;OK;nic.is;3;172.31.1.16;600
	      MTR.0.86+git:16e39fc0;1435562787;OK;nic.is;4;82.221.168.236;1163
	      MTR.0.86+git:16e39fc0;1435562787;OK;nic.is;5;???;0
	      MTR.0.86+git:16e39fc0;1435562787;OK;nic.is;6;rix-k2-gw.isnic.is;1654
	      MTR.0.86+git:16e39fc0;1435562787;OK;nic.is;7;www.isnic.is;1036

       -j, --json
	      Use this option to tell mtr to use the JSON output format.  This
	      format is better suited for automated processing of the measure-
	      ment results.

       -p, --split
	      Use this option to set mtr to spit out a format that is suitable
	      for a split-user interface.

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

       -b, --show-ips
	      Use  this	 option to tell mtr to display both the host names and
	      numeric IP numbers.  In split mode this adds an extra  field  to
	      the  output.   In report mode, there is usually too little space
	      to add the IPs, and they will be truncated.  Use the wide report
	      (-w) mode to see the IPs in report mode.

       -o FIELDS, --order FIELDS
	      Use  this option to specify which fields to display and in which
	      order.  You may use one or more  space  characters  to  separate
	      fields.
	      Available fields:

				 +--+---------------------+
				 |L | Loss ratio	  |
				 +--+---------------------+
				 |D | Dropped packets	  |
				 +--+---------------------+
				 |R | Received packets	  |
				 +--+---------------------+
				 |S | Sent Packets	  |
				 +--+---------------------+
				 |N | Newest RTT(ms)	  |
				 +--+---------------------+
				 |B | Min/Best RTT(ms)	  |
				 +--+---------------------+
				 |A | Average RTT(ms)	  |
				 +--+---------------------+
				 |W | Max/Worst RTT(ms)	  |
				 +--+---------------------+
				 |V | Standard Deviation  |
				 +--+---------------------+
				 |G | Geometric Mean	  |
				 +--+---------------------+
				 |J | Current Jitter	  |
				 +--+---------------------+
				 |M | Jitter Mean/Avg.	  |
				 +--+---------------------+
				 |X | Worst Jitter	  |
				 +--+---------------------+
				 |I | Interarrival Jitter |
				 +--+---------------------+
	      Example: -o "LSD NBAW  X"

       -y n, --ipinfo n
	      Displays information about each IP hop.  Valid values for n are:

	      0	  Display AS number (equivalent to -z)
	      1	  Display IP prefix
	      2	  Display country code of the origin AS
	      3	  Display RIR (ripencc, arin, ...)
	      4	  Display the allocation date of the IP prefix

	      It  is  possible to cycle between these fields at runtime (using
	      the y key).

       -z, --aslookup
	      Displays the Autonomous System (AS) number alongside  each  hop.
	      Equivalent to --ipinfo 0.

	      Example (columns to the right not shown for clarity):
	      1. AS???	 r-76520-PROD.greenqloud.internal
	      2. AS51969 46.149.16.4
	      3. AS???	 172.31.1.16
	      4. AS30818 82.221.168.236
	      5. ???
	      6. AS???	 rix-k2-gw.isnic.is
	      7. AS1850	 www.isnic.is

       -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.  The root user may choose values between zero
	      and one.

       -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.

       -s PACKETSIZE, --psize PACKETSIZE
	      This option sets the packet size used for	 probing.   It	is  in
	      bytes, inclusive IP and ICMP headers.

	      If  set to a negative number, every iteration will use a differ-
	      ent, random packet size up to that number.

       -B NUM, --bitpattern NUM
	      Specifies bit pattern to use in payload.	Should be within range
	      0 - 255.	If NUM is greater than 255, a random pattern is used.

       -G SECONDS, --gracetime SECONDS
	      Use  this	 option	 to  specify the positive number of seconds to
	      wait for responses after the final request. The default value is
	      five seconds.

       -Q NUM, --tos NUM
	      Specifies	 value for type of service field in IP header.	Should
	      be within range 0 - 255.

       -e, --mpls
	      Use this option to tell mtr to  display  information  from  ICMP
	      extensions  for MPLS (RFC 4950) that are encoded in the response
	      packets.

       -a ADDRESS, --address ADDRESS
	      Use this option to bind the outgoing socket to ADDRESS, so  that
	      all  packets  will be sent with ADDRESS as source address.  NOTE
	      that this option doesn't apply to DNS requests (which  could  be
	      and could not be what you want).

       -f NUM, --first-ttl NUM
	      Specifies with what TTL to start.	 Defaults to 1.

       -m NUM, --max-ttl NUM
	      Specifies	 the  maximum  number of hops (max time-to-live value)
	      traceroute will probe.  Default is 30.

       -U NUM, --max-unknown NUM
	      Specifies the maximum unknown host. Default is 5.

       -u, --udp
	      Use UDP datagrams instead of ICMP ECHO.

       -T, --tcp
	      Use TCP  SYN  packets  instead  of  ICMP	ECHO.	PACKETSIZE  is
	      ignored, since SYN packets can not contain data.

       -S, --sctp
	      Use Stream Control Transmission Protocol packets instead of ICMP
	      ECHO.

       -P PORT, --port PORT
	      The target port number for TCP/SCTP/UDP traces.

       -L LOCALPORT, --localport LOCALPORT
	      The source port number for UDP traces.

       -Z SECONDS, --timeout SECONDS
	      The number of seconds to keep probe sockets open	before	giving
	      up  on  the connection.  Using large values for this, especially
	      combined with a short interval,  will  use  up  a	 lot  of  file
	      descriptors.

       -M MARK, --mark MARK
	      Set the mark for each packet sent through this socket similar to
	      the netfilter MARK target but socket-based.  MARK is 32 unsigned
	      integer.	 See  socket(7)	 for  full  description of this socket
	      option.

ENVIRONMENT
       mtr recognizes a few environment variables.

       MTR_OPTIONS
	      This environment variable allows to specify options, as if  they
	      were  passed  on	the command line.  It is parsed before reading
	      the actual command line options, so that	options	 specified  in
	      MTR_OPTIONS are overridden by command-line options.

	      Example:

	      MTR_OPTIONS="-4 -c 1" mtr -6 localhost

	      would  send  one probe (because of -c 1) towards ::1 (because of
	      -6, which overrides the -4 passed in MTR_OPTIONS).

       MTR_PACKET
	      A path to the mtr-packet executable, to be used for sending  and
	      receiving network probes.	 If MTR_PACKET is unset, the PATH will
	      be used to search for an mtr-packet executable.

       DISPLAY
	      Specifies an X11 server for the GTK+ frontend.

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 reliability
       of these routers.

CONTACT INFORMATION
       For  the latest version, see the mtr web page at <http://www.bitwizard.
       nl/mtr/>

       For patches, bug reports, or feature requests, please open an issue  on
       GitHub at: <https://github.com/traviscross/mtr>.

SEE ALSO
       mtr-packet(8),  traceroute(8),  ping(8),	 socket(7), TCP/IP Illustrated
       (Stevens, ISBN 0201633469).



mtr				     0.92				MTR(8)