ping(1M) ping(1M)
NAME
ping - send ICMP ECHOREQUEST packets to other systems
SYNOPSIS
/usr/sbin/ping system [timeout]
/usr/sbin/ping [-n] [-s] [-lrRvL] [-t ttl] [-i addr] system [datasize]
[count]
DESCRIPTION
ping utilizes the ICMP protocol's ECHOREQUEST datagram to elicit an
ICMP ECHORESPONSE from the specified system or network gateway. If
system responds, ping will print "system is alive" on the standard
output and exit. Otherwise after timeout seconds, it will write "no
answer from system". The default value of timeout is 20 seconds.
When using ping for fault isolation, first ping the local system to
verify that the local network interface is running.
OPTIONS
-n Displays the network addresses as numbers. ping normally outputs
the addresses as symbols. Use the -n option to avoid costly
transmissions of addresses as symbolic names.
-s When the -s flag is specified, ping sends one datagram per
second, and prints one line of output for every ECHORESPONSE
that it receives. No output is produced 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 datagram packet size is 64
bytes, or you can specify a size with the datasize command-line
argument (datagram packet size is datasize + ICMP header). If an
optional count is given, ping sends only that number of requests.
-l Loose source route. Use this option in the IP header to send the
packet to the given host and back again. Usually specified with
the -R 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 been dropped by the
router daemon [see routed(1M)].
-R Record route. Sets the IP record route option, which will store
the route of the packet inside the IP header. The contents of the
record route will only be printed if the -v option is given, and
only be set on return packets if the target host preserves the
record route option across echos, or the -l option is given.
-v Verbose output. List any ICMP packets, other than ECHORESPONSE,
that are received.
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ping(1M) ping(1M)
Multicast Options
-L Disable multicast loopback. This option gives explicit control
over whether or not subsequent datagrams are looped back.
-t ttl
This option changes the time-to-live (TTL) for outgoing multicast
datagrams to ttl. Datagrams with a TTL of 1 are not forwarded
beyond the local network. Multicast datagrams with a TTL of 0
will not be transmitted on any network, but may be delivered
locally if the sending host belongs to the destination group and
if multicast loopback has not been disabled on the sending
socket. Multicast datagrams with TTL greater than 1 may be for-
warded to other networks if a multicast router is attached to the
local network. ttl ranges from 0 to 255.
-i addr
You use this option to define the interface for sending ICMP
packets. The interface is specified using the local IP address of
the interface or INADDRANY to specify the default interface. The
-i option is only expedient if for system a multicast group is
accessed by means of ping.
SEE ALSO
ifconfig(1M), netstat(1M), rpcinfo(1M), icmp(7).
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