source: rtems-docs/shell/network_commands.rst @ 9aafb39

.. comment SPDX-License-Identifier: CC-BY-SA-4.0

.. COMMENT: COPYRIGHT (c) 1988-2008.
.. COMMENT: On-Line Applications Research Corporation (OAR).
.. COMMENT: All rights reserved.

Network Commands
################

Introduction
============

The RTEMS shell has the following network commands:

- netstats_ - obtain network statistics

- ifconfig_ - configure a network interface

- route_ - show or manipulate the IP routing table

- ping_ - ping a host or IP address

Commands
========

This section details the Network Commands available.  A subsection is dedicated
to each of the commands and describes the behavior and configuration of that
command as well as providing an example usage.

.. _netstats:

netstats - obtain network statistics
------------------------------------
.. index:: netstats

**SYNOPSYS:**

.. code:: shell

    netstats [-Aimfpcut]

**DESCRIPTION:**

This command is used to display various types of network statistics.  The
information displayed can be specified using command line arguments in various
combinations.  The arguments are interpreted as follows:

*-A*
    print All statistics

*-i*
    print Inet Routes

*-m*
    print MBUF Statistics

*-f*
    print IF Statistics

*-p*
    print IP Statistics

*-c*
    print ICMP Statistics

*-u*
    print UDP Statistics

*-t*
    print TCP Statistics

**EXIT STATUS:**

This command returns 0 on success and non-zero if an error is encountered.

**NOTES:**

NONE

**EXAMPLES:**

The following is an example of using the ``netstats`` command to print the IP
routing table:

.. code:: shell

    [/] $ netstats -i
    Destination     Gateway/Mask/Hw    Flags     Refs     Use Expire Interface
    default         192.168.1.14       UGS         0        0      0 eth1
    192.168.1.0     255.255.255.0      U           0        0      1 eth1
    192.168.1.14    00:A0:C8:1C:EE:28  UHL         1        0   1219 eth1
    192.168.1.51    00:1D:7E:0C:D0:7C  UHL         0      840   1202 eth1
    192.168.1.151   00:1C:23:B2:0F:BB  UHL         1       23   1219 eth1

The following is an example of using the ``netstats`` command to print the MBUF
statistics:

.. code:: shell

    [/] $ netstats -m
    ************ MBUF STATISTICS ************
    mbufs:2048    clusters: 128    free:  63
    drops:   0       waits:   0  drains:   0
    free:1967          data:79          header:2           socket:0
    pcb:0           rtable:0           htable:0           atable:0
    soname:0           soopts:0           ftable:0           rights:0
    ifaddr:0          control:0          oobdata:0

The following is an example of using the ``netstats`` command to print the
print the interface statistics:

.. code:: shell

    [/] $ netstats -f
    ************ INTERFACE STATISTICS ************
    ***** eth1 *****
    Ethernet Address: 00:04:9F:00:5B:21
    Address:192.168.1.244   Broadcast Address:192.168.1.255   Net mask:255.255.255.0
    Flags: Up Broadcast Running Active Multicast
    Send queue limit:50   length:1    Dropped:0
    Rx Interrupts:889            Not First:0               Not Last:0
    Giant:0              Non-octet:0
    Bad CRC:0                Overrun:0              Collision:0
    Tx Interrupts:867             Deferred:0         Late Collision:0
    Retransmit Limit:0               Underrun:0             Misaligned:0

The following is an example of using the ``netstats`` command to print the
print IP statistics:

.. code:: shell

    [/] $ netstats -p
    ************ IP Statistics ************
    total packets received                    894
    packets rcvd for unreachable dest          13
    datagrams delivered to upper level        881
    total ip packets generated here           871

The following is an example of using the ``netstats`` command to print the ICMP
statistics:

.. code:: shell

    [/] $ netstats -c
    ************ ICMP Statistics ************
    Type 0 sent                 843
    number of responses         843
    Type 8 received             843

The following is an example of using the ``netstats`` command to print the UDP
statistics:

.. code:: shell

    [/] $ netstats -u
    ************ UDP Statistics ************

The following is an example of using the ``netstats`` command to print the TCP
statistics:

.. code:: shell

    [/] $ netstats -t
    ************ TCP Statistics ************
    connections accepted           1
    connections established           1
    segs where we tried to get rtt          34
    times we succeeded          35
    delayed acks sent           2
    total packets sent          37
    data packets sent          35
    data bytes sent        2618
    ack-only packets sent           2
    total packets received          47
    packets received in sequence          12
    bytes received in sequence         307
    rcvd ack packets          35
    bytes acked by rcvd acks        2590
    times hdr predict ok for acks          27
    times hdr predict ok for data pkts          10

**CONFIGURATION:**

.. index:: CONFIGURE_SHELL_NO_COMMAND_NETSTATS
.. index:: CONFIGURE_SHELL_COMMAND_NETSTATS

This command is included in the default shell command set.  When building a
custom command set, define ``CONFIGURE_SHELL_COMMAND_NETSTATS`` to have this
command included.

This command can be excluded from the shell command set by defining
``CONFIGURE_SHELL_NO_COMMAND_NETSTATS`` when all shell commands have been
configured.

**PROGRAMMING INFORMATION:**

.. index:: rtems_shell_rtems_main_netstats

The ``netstats`` is implemented by a C language function
which has the following prototype:

.. code:: c

    int rtems_shell_rtems_main_netstats(
        int    argc,
        char **argv
    );

The configuration structure for the ``netstats`` has the following prototype:

.. code:: c

    extern rtems_shell_cmd_t rtems_shell_NETSTATS_Command;

.. _ifconfig:

ifconfig - configure a network interface
----------------------------------------
.. index:: ifconfig

**SYNOPSYS:**

.. code:: shell

    ifconfig
    ifconfig interface
    ifconfig interface \[up|down]
    ifconfig interface \[netmask|pointtopoint|broadcast] IP

**DESCRIPTION:**

This command may be used to display information about the network interfaces in
the system or configure them.

**EXIT STATUS:**

This command returns 0 on success and non-zero if an error is encountered.

**NOTES:**

Just like its counterpart on GNU/Linux and BSD systems, this command is
complicated.  More example usages would be a welcome submission.

**EXAMPLES:**

The following is an example of how to use ``ifconfig``:

.. code:: shell

    ************ INTERFACE STATISTICS ************
    ***** eth1 *****
    Ethernet Address: 00:04:9F:00:5B:21
    Address:192.168.1.244   Broadcast Address:192.168.1.255   Net mask:255.255.255.0
    Flags: Up Broadcast Running Active Multicast
    Send queue limit:50   length:1    Dropped:0
    Rx Interrupts:5391           Not First:0               Not Last:0
    Giant:0              Non-octet:0
    Bad CRC:0                Overrun:0              Collision:0
    Tx Interrupts:5256            Deferred:0         Late Collision:0
    Retransmit Limit:0               Underrun:0             Misaligned:0

**CONFIGURATION:**

.. index:: CONFIGURE_SHELL_NO_COMMAND_IFCONFIG
.. index:: CONFIGURE_SHELL_COMMAND_IFCONFIG

This command is included in the default shell command set.  When building a
custom command set, define ``CONFIGURE_SHELL_COMMAND_IFCONFIG`` to have this
command included.

This command can be excluded from the shell command set by defining
``CONFIGURE_SHELL_NO_COMMAND_IFCONFIG`` when all shell commands have been
configured.

**PROGRAMMING INFORMATION:**

.. index:: rtems_shell_rtems_main_ifconfig

The ``ifconfig`` is implemented by a C language function which has the
following prototype:

.. code:: c

    int rtems_shell_rtems_main_ifconfig(
        int    argc,
        char **argv
    );

The configuration structure for the ``ifconfig`` has the following prototype:

.. code:: c

    extern rtems_shell_cmd_t rtems_shell_IFCONFIG_Command;

.. _route:

route - show or manipulate the ip routing table
-----------------------------------------------
.. index:: route

**SYNOPSYS:**

.. code:: shell

    route [subcommand] [args]

**DESCRIPTION:**

This command is used to display and manipulate the routing table.  When invoked
with no arguments, the current routing information is displayed.  When invoked
with the subcommands ``add`` or ``del``, then additional arguments must be
provided to describe the route.

Command templates include the following:

.. code:: shell

    route [add|del] -net IP_ADDRESS gw GATEWAY_ADDRESS [netmask MASK]
    route [add|del] -host IP_ADDRESS gw GATEWAY_ADDRES [netmask MASK]

When not provided the netmask defaults to ``255.255.255.0``

**EXIT STATUS:**

This command returns 0 on success and non-zero if an error is encountered.

**NOTES:**

Just like its counterpart on GNU/Linux and BSD systems, this command is
complicated.  More example usages would be a welcome submission.

**EXAMPLES:**

The following is an example of how to use ``route`` to display, add, and delete
a new route:

.. code:: c

    [/] $ route
    Destination     Gateway/Mask/Hw    Flags     Refs     Use Expire Interface
    default         192.168.1.14       UGS         0        0      0 eth1
    192.168.1.0     255.255.255.0      U           0        0      1 eth1
    192.168.1.14    00:A0:C8:1C:EE:28  UHL         1        0   1444 eth1
    192.168.1.51    00:1D:7E:0C:D0:7C  UHL         0    10844   1202 eth1
    192.168.1.151   00:1C:23:B2:0F:BB  UHL         2       37   1399 eth1
    [/] $ route add -net 192.168.3.0 gw 192.168.1.14
    [/] $ route
    Destination     Gateway/Mask/Hw    Flags     Refs     Use Expire Interface
    default         192.168.1.14       UGS         0        0      0 eth1
    192.168.1.0     255.255.255.0      U           0        0      1 eth1
    192.168.1.14    00:A0:C8:1C:EE:28  UHL         2        0   1498 eth1
    192.168.1.51    00:1D:7E:0C:D0:7C  UHL         0    14937   1202 eth1
    192.168.1.151   00:1C:23:B2:0F:BB  UHL         2       96   1399 eth1
    192.168.3.0     192.168.1.14       UGS         0        0      0 eth1
    [/] $ route del -net 192.168.3.0 gw 192.168.1.14
    [/] $ route
    Destination     Gateway/Mask/Hw    Flags     Refs     Use Expire Interface
    default         192.168.1.14       UGS         0        0      0 eth1
    192.168.1.0     255.255.255.0      U           0        0      1 eth1
    192.168.1.14    00:A0:C8:1C:EE:28  UHL         1        0   1498 eth1
    192.168.1.51    00:1D:7E:0C:D0:7C  UHL         0    15945   1202 eth1
    192.168.1.151   00:1C:23:B2:0F:BB  UHL         2      117   1399 eth1

**CONFIGURATION:**

.. index:: CONFIGURE_SHELL_NO_COMMAND_ROUTE
.. index:: CONFIGURE_SHELL_COMMAND_ROUTE

This command is included in the default shell command set.  When building a
custom command set, define ``CONFIGURE_SHELL_COMMAND_ROUTE`` to have this
command included.

This command can be excluded from the shell command set by defining
``CONFIGURE_SHELL_NO_COMMAND_ROUTE`` when all shell commands have been
configured.

**PROGRAMMING INFORMATION:**

.. index:: rtems_shell_rtems_main_route

The ``route`` is implemented by a C language function which has the following
prototype:

.. code:: c

    int rtems_shell_rtems_main_route(
        int    argc,
        char **argv
    );

The configuration structure for the ``route`` has the following prototype:

.. code:: c

    extern rtems_shell_cmd_t rtems_shell_ROUTE_Command;

.. _ping:

ping - ping a host or IP address
--------------------------------
.. index:: ping

**SYNOPSYS:**

.. code:: shell

    ping [-AaDdfnoQqRrv] [-c count] [-G sweepmaxsize] [-g sweepminsize]
    [-h sweepincrsize] [-i wait] [-l preload] [-M mask | time] [-m ttl]
    [-p pattern] [-S src_addr] [-s packetsize] [-t timeout]
    [-W waittime] [-z tos] host
    ping [-AaDdfLnoQqRrv] [-c count] [-I iface] [-i wait] [-l preload]
    [-M mask | time] [-m ttl] [-p pattern] [-S src_addr]
    [-s packetsize] [-T ttl] [-t timeout] [-W waittime]
    [-z tos] mcast-group

**DESCRIPTION:**

The ping utility uses the ICMP protocol's mandatory ECHO_REQUEST datagram to
elicit an ICMP ECHO_RESPONSE from a host or gateway.  ECHO_REQUEST datagrams
("pings") have an IP and ICMP header, followed by a "struct timeval" and then
an arbitrary number of "pad" bytes used to fill out the packet.  The options
are as follows:

*-A*
    Audible.  Output a bell (ASCII 0x07) character when no packet is received
    before the next packet is transmitted.  To cater for round-trip times that
    are longer than the interval between transmissions, further missing packets
    cause a bell only if the maximum number of unreceived packets has
    increased.

*-a*
    Audible.  Include a bell (ASCII 0x07) character in the output when any
    packet is received.  This option is ignored if other format options are
    present.

*-c count*
    Stop after sending (and receiving) count ECHO_RESPONSE packets.  If this
    option is not specified, ping will operate until interrupted.  If this
    option is specified in conjunction with ping sweeps, each sweep will
    consist of count packets.

*-D*
    Set the Don't Fragment bit.

*-d*
    Set the SO_DEBUG option on the socket being used.

*-f*
    Flood ping. Outputs packets as fast as they come back or one hundred times
    per second, whichever is more.  For every ECHO_REQUEST sent a period "." is
    printed, while for every ECHO_REPLY received a backspace is printed.  This
    provides a rapid display of how many packets are being dropped.  Only the
    super-user may use this option.  This can be very hard on a network and
    should be used with caution.

*-G sweepmaxsize*
    Specify the maximum size of ICMP payload when sending sweeping pings.  This
    option is required for ping sweeps.

*-g sweepminsize*
    Specify the size of ICMP payload to start with when sending sweeping pings.
    The default value is 0.

*-h sweepincrsize*
    Specify the number of bytes to increment the size of ICMP payload after
    each sweep when sending sweeping pings.  The default value is 1.

*-I iface*
    Source multicast packets with the given interface address.  This flag only
    applies if the ping destination is a multicast address.

*-i wait*
    Wait wait seconds between sending each packet.  The default is to wait for
    one second between each packet.  The wait time may be fractional, but only
    the super-user may specify values less than 1 second.  This option is
    incompatible with the -f option.

*-L*
    Suppress loopback of multicast packets.  This flag only applies if the ping
    destination is a multicast address.

*-l preload*
    If preload is specified, ping sends that many packets as fast as possible
    before falling into its normal mode of behavior.  Only the super-user may
    use this option.

*-M mask | time*
    Use ICMP_MASKREQ or ICMP_TSTAMP instead of ICMP_ECHO.  For mask, print the
    netmask of the remote machine.  Set the net.inet.icmp.maskrepl MIB variable
    to enable ICMP_MASKREPLY.  For time, print the origination, reception and
    transmission timestamps.

*-m ttl*
    Set the IP Time To Live for outgoing packets.  If not specified, the kernel
    uses the value of the net.inet.ip.ttl MIB variable.

*-n*
    Numeric output only.  No attempt will be made to lookup symbolic names for
    host addresses.

*-o*
    Exit successfully after receiving one reply packet.

*-p pattern*
    You may specify up to 16 "pad" bytes to fill out the packet you send.  This
    is useful for diagnosing data-dependent problems in a network.  For
    example, "-p ff" will cause the sent packet to be filled with all ones.

*-Q*
    Somewhat quiet output.  Don't display ICMP error messages that are in
    response to our query messages.  Originally, the -v flag was required to
    display such errors, but -v displays all ICMP error messages.  On a busy
    machine, this output can be overbear- ing.  Without the -Q flag, ping
    prints out any ICMP error mes- sages caused by its own ECHO_REQUEST
    messages.

*-q*
    Quiet output.  Nothing is displayed except the summary lines at startup
    time and when finished.

*-R*
    Record route.  Includes the RECORD_ROUTE option in the ECHO_REQUEST packet
    and displays the route buffer on returned packets.  Note that the IP header
    is only large enough for nine such routes; the traceroute(8) command is
    usually better at determining the route packets take to a particular
    destination.  If more routes come back than should, such as due to an
    illegal spoofed packet, ping will print the route list and then truncate it
    at the correct spot.  Many hosts ignore or discard the RECORD_ROUTE option.

*-r*
    Bypass the normal routing tables and send directly to a host on an attached
    network.  If the host is not on a directly-attached network, an error is
    returned.  This option can be used to ping a local host through an
    interface that has no route through it (e.g., after the interface was
    dropped).

*-S src_addr*
    Use the following IP address as the source address in outgoing packets.  On
    hosts with more than one IP address, this option can be used to force the
    source address to be something other than the IP address of the interface
    the probe packet is sent on.  If the IP address is not one of this
    machine's interface addresses, an error is returned and nothing is sent.

*-s packetsize*
    Specify the number of data bytes to be sent.  The default is 56, which
    translates into 64 ICMP data bytes when combined with the 8 bytes of ICMP
    header data.  Only the super-user may specify val- ues more than default.
    This option cannot be used with ping sweeps.

*-T ttl*
    Set the IP Time To Live for multicasted packets.  This flag only applies if
    the ping destination is a multicast address.

*-t timeout*
    Specify a timeout, in seconds, before ping exits regardless of how many
    packets have been received.

*-v*
    Verbose output.  ICMP packets other than ECHO_RESPONSE that are received
    are listed.

*-W waittime*
    Time in milliseconds to wait for a reply for each packet sent.  If a reply
    arrives later, the packet is not printed as replied, but considered as
    replied when calculating statistics.

*-z tos*
    Use the specified type of service.

**EXIT STATUS:**

The ping utility exits with one of the following values:

0    At least one response was heard from the specified host.

2    The transmission was successful but no responses were
     received.

any other value an error occurred.  These values are defined in <sysexits.h>.

**NOTES:**

When using ping for fault isolation, it should first be run on the local host,
to verify that the local network interface is up and running.  Then, hosts and
gateways further and further away should be "pinged".  Round-trip times and
packet loss statistics are computed.  If duplicate packets are received, they
are not included in the packet loss calculation, although the round trip time
of these packets is used in calculating the round-trip time statistics.  When
the specified number of packets have been sent a brief summary is displayed,
showing the number of packets sent and received, and the minimum, mean,
maximum, and standard deviation of the round-trip times.

This program is intended for use in network testing, measurement and
management.  Because of the load it can impose on the network, it is unwise to
use ping during normal operations or from automated scripts.

This command can fail if more than the FD_SET size number of file descriptors
are open.

**EXAMPLES:**

The following is an example of how to use ``oing`` to ping:

.. code:: shell

    [/] # ping 10.10.10.1
    PING 10.10.10.1 (10.10.10.1): 56 data bytes
    64 bytes from 10.10.10.1: icmp_seq=0 ttl=63 time=0.356 ms
    64 bytes from 10.10.10.1: icmp_seq=1 ttl=63 time=0.229 ms
    64 bytes from 10.10.10.1: icmp_seq=2 ttl=63 time=0.233 ms
    64 bytes from 10.10.10.1: icmp_seq=3 ttl=63 time=0.235 ms
    64 bytes from 10.10.10.1: icmp_seq=4 ttl=63 time=0.229 ms
    --- 10.10.10.1 ping statistics ---
    5 packets transmitted, 5 packets received, 0.0% packet loss
    round-trip min/avg/max/stddev = 0.229/0.256/0.356/0.050 ms
    [/] # ping -f -c 10000  10.10.10.1
    PING 10.10.10.1 (10.10.10.1): 56 data bytes
    .
    --- 10.10.10.1 ping statistics ---
    10000 packets transmitted, 10000 packets received, 0.0% packet loss
    round-trip min/avg/max/stddev = 0.154/0.225/0.533/0.027 ms

**CONFIGURATION:**

.. index:: CONFIGURE_SHELL_NO_COMMAND_PING
.. index:: CONFIGURE_SHELL_COMMAND_PING

This command is included in the default shell command set.  When building a
custom command set, define ``CONFIGURE_SHELL_COMMAND_PING`` to have this
command included.

This command can be excluded from the shell command set by defining
``CONFIGURE_SHELL_NO_COMMAND_PING`` when all shell commands have been
configured.

**PROGRAMMING INFORMATION:**

.. index:: rtems_shell_rtems_main_ping

The ``ping`` is implemented by a C language function which has the following
prototype:

.. code:: c

    int rtems_shell_rtems_main_ping(
        int    argc,
        char **argv
    );

The configuration structure for the ``ping`` has the following prototype:

.. code:: c

    extern rtems_shell_cmd_t rtems_shell_PING_Command;