System Administration Commands ping(1M)



NAME
ping - send ICMP (ICMP6) ECHO_REQUEST packets to network
hosts

SYNOPSIS
/usr/sbin/ping host [timeout]

/usr/sbin/ping -s [-l | -U] [-adlLnrRv] [-A addr_family]
[-c traffic_class] [-g gateway [ -g gateway...]] [-
F flow_label] [-I interval] [-i interface] [-P tos] [-
p port] [-t ttl] host [data_size] [npackets]

DESCRIPTION
The utility ping utilizes the ICMP (ICMP6 in IPv6)
protocol's ECHO_REQUEST datagram to elicit an ICMP (ICMP6)
ECHO_RESPONSE from the specified host or network gateway. If
host responds, ping will print:


host is alive


on the standard output and exit. Otherwise, after timeout
seconds, it will write:


no answer from host


The default value of timeout is 20 seconds.

When you specify the s flag, sends one datagram per second
(adjust with -I) and prints one line of output for every
ECHO_RESPONSE that it receives. ping produces no output if
there is no response. In this second form, ping computes
round trip times and packet loss statistics; it displays a
summary of this information upon termination or timeout. The
default data_size is 56 bytes, or you can specify a size
with the data_size command-line argument. If you specify the
optional npackets, ping sends ping requests until it either
sends npackets requests or receives npackets replies.

When using ping for fault isolation, first ping the local
host to verify that the local network interface is running.

OPTIONS
The following options are supported:

-A addr_family
Specify the address family of the target host.
addr_family can be either inet or inet6. Address
family determines which protocol to use. For an



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System Administration Commands ping(1M)



argument of inet, IPv4 is used. For inet6, IPv6
is used.

By default, if the name of a host is provided,
not the literal IP address, and a valid IPv6
address exists in the name service database, ping
will use this address. Otherwise, if the name
service database contains an IPv4 address, it
will try the IPv4 address.

Specify the address family inet or inet6 to over-
ride the default behavior. If the argument speci-
fied is inet, ping will use the IPv4 address
associated with the host name. If none exists,
ping will state that the host is unknown and
exit. It does not try to determine if an IPv6
address exists in the name service database.

If the specified argument is inet6, ping uses the
IPv6 address that is associated with the host
name. If none exists, ping states that the host
is unknown and exits.

-F flow_label
Specify the flow label of probe packets. The
value must be an integer in the range from 0 to
1048575. This option is valid only on IPv6.

-I interval
Turn on the statistics mode and specify the
interval between successive transmissions. The
default is one second. See the discussion of the
-s option.

-L Turn off loopback of multicast packets. Normally,
members are in the host group on the outgoing
interface, a copy of the multicast packets will
be delivered to the local machine.

-P tos
Set the type of service (tos) in probe packets to
the specified value. The default is zero. The
value must be an integer in the range from 0 to
255. Gateways also in the path can route the
probe packet differently, depending upon the
value of tos that is set in the probe packet.
This option is valid only on IPv4.

-R Record route. Sets the IPv4 record route option,
which stores the route of the packet inside the
IPv4 header. The contents of the record route are
only printed if the -v and -s options are given.



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System Administration Commands ping(1M)



They are only set on return packets if the target
host preserves the record route option across
echos, or the -l option is given. This option is
valid only on IPv4.

-U Send UDP packets instead of ICMP (ICMP6) packets.
ping sends UDP packets to consecutive ports
expecting to receive back ICMP (ICMP6)
PORT_UNREACHABLE from the target host.

-a ping all addresses, both IPv4 and IPv6, of the
multihomed destination. The output appears as if
ping has been run once for each IP address of the
destination. If this option is used together with
-A, ping probes only the addresses that are of
the specified address family. When used with the
-s option and npackets is not specified, ping
continuously probes the destination addresses in
a round robin fashion. If npackets is specified,
ping sends npackets number of probes to each IP
address of the destination and then exits.

-c traffic_class
Specify the traffic class of probe packets. The
value must be an integer in the range from 0 to
255. Gateways along the path can route the probe
packet differently, depending upon the value of
traffic_class set in the probe packet. This
option is valid only on IPv6.

-d Set the SO_DEBUG socket option.

-g gateway
Specify a loose source route gateway so that the
probe packet goes through the specified host
along the path to the target host. The maximum
number of gateways is 8 for IPv4 and 127 for
IPv6. Note that some factors such as the link MTU
can further limit the number of gateways for
IPv6.

-i interface_address
Specify the outgoing interface address to use for
multicast packets for IPv4 and both multicast and
unicast packets for IPv6. The default interface
address for multicast packets is determined from
the (unicast) routing tables. interface_address
can be a literal IP address, for example,
10.123.100.99, or an interface name, for example,
le0, or an interface index, for example 2.

-l Use to send the probe packet to the given host



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System Administration Commands ping(1M)



and back again using loose source routing. Usu-
ally specified with the -R option. If any gate-
ways are specified using -g, they are visited
twice, both to and from the destination. This
option is ignored if the -U option is used.

-n Show network addresses as numbers. ping normally
does a reverse name lookup on the IP addresses it
extracts from the packets received. The -n option
blocks the reverse lookup, so ping prints IP
addresses instead of host names.

-p port
Set the base UDP port number used in probes. This
option is used with the -U option. The default
base port number is 33434. The ping utility
starts setting the destination port number of UDP
packets to this base and increments it by one at
each probe.

-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
been dropped by the router daemon. See
in.routed(1M).

-s Send one datagram per second and collect statis-
tics.

-t ttl
Specify the IPv4 time to live, or IPv6 hop limit,
for unicast and multicast packets. The default
time to live (hop limit) for unicast packets can
be set with ndd(1M) using the icmp_ipv4_ttl vari-
able for IPv4 and the icmp_ipv6_ttl variable for
IPv6. The default time to live (hop limit) for
multicast is one hop.

-v Verbose output. List any ICMP (ICMP6) packets,
other than replies from the target host.


OPERANDS
host The network host

EXAMPLES
Example 1: Using ping With IPv6

This example shows ping sending probe packets to all the
IPv6 addresses of the host london, one at a time. It sends



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System Administration Commands ping(1M)



an ICMP6 ECHO_REQUEST every second until the user interrupts
it.

istanbul% ping -s -A inet6 -a london
PING london: 56 data bytes
64 bytes from london (4::114:a00:20ff:ab3d:83ed): icmp_seq=0. time=2. ms
64 bytes from london (fec0::114:a00:20ff:ab3d:83ed): icmp_seq=1. time=1. ms
64 bytes from london (4::114:a00:20ff:ab3d:83ed): icmp_seq=2. time=1. ms
64 bytes from london (fec0::114:a00:20ff:ab3d:83ed): icmp_seq=3. time=1. ms
64 bytes from london (4::114:a00:20ff:ab3d:83ed): icmp_seq=4. time=1. ms
64 bytes from london (fec0::114:a00:20ff:ab3d:83ed): icmp_seq=5. time=1. ms
^C
----london PING Statistics----
6 packets transmitted, 6 packets received, 0% packet loss
round-trip (ms) min/avg/max = 1/1/2

EXIT STATUS
The following exit values are returned:

0 Successful operation; the machine is alive.

non-zero
An error has occurred. Either a malformed argument has
been specified, or the machine was not alive.

ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:

____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | SUNWbip |
|_____________________________|_____________________________|


SEE ALSO
ifconfig(1M), in.routed(1M), ndd(1M), netstat(1M),
rpcinfo(1M), traceroute(1M), attributes(5), icmp(7P),
icmp6(7P)















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