Specifications

-o (only for
Windows, from v1.2
or higher)
. Redirect output to given file.
-c, --client
host
$IPERF_CLIENT
If Iperf is in server mode, then specifying a host with -c will
limit the connections that Iperf will accept to the host specified.
Does not work well for UDP.
-P, --parallel
#
$IPERF_PARALLEL
The number of connections to handle by the server before
closing. Default is 0 (which means to accept connections
forever).
Client specific options
-b, --
bandwidth
#[KM]
$IPERF_BANDWIDTH
The UDP bandwidth to send at, in bits/sec. This implies the -u
option. Default is 1 Mbit/sec.
-c, --client
host
$IPERF_CLIENT
Run Iperf in client mode, connecting to an Iperf server running
on host.
-d, --dualtest $IPERF_DUALTEST
Run Iperf in dual testing mode. This will cause the server to
connect back to the client on the port specified in the
-L option
(or defaults to the port the client connected to the server on).
This is done immediately therefore running the tests
simultaneously. If you want an alternating test try
-r.
-n, --num
#[KM]
$IPERF_NUM
The number of buffers to transmit. Normally, Iperf sends for 10
seconds. The -n option overrides this and sends an array of len
bytes num times, no matter how long that takes. See also the
-l
and -t options.
-r, --tradeoff $IPERF_TRADEOFF
Run Iperf in tradeoff testing mode. This will cause the server to
connect back to the client on the port specified in the
-L option
(or defaults to the port the client connected to the server on).
This is done following the client connection termination,
therefore running the tests alternating. If you want an
simultaneous test try
-d.
-t, --time # $IPERF_TIME
The time in seconds to transmit for. Iperf normally works by
repeatedly sending an array of len bytes for time seconds.
Default is 10 seconds. See also the
-l and -n options.
-L, --
listenport #
$IPERF_LISTENPORT
This specifies the port that the server will connect back to the
client on. It defaults to the port used to connect to the server
from the client.
-P, --parallel
#
$IPERF_PARALLEL
The number of simultaneous connections to make to the server.
Default is 1. Requires thread support on both the client and
server.
-S, --tos # $IPERF_TOS
The type-of-service for outgoing packets. (Many routers ignore
the TOS field.) You may specify the value in hex with a '0x'
prefix, in octal with a '0' prefix, or in decimal. For example,
'0x10' hex = '020' octal = '16' decimal. The TOS numbers
specified in RFC 1349 are:
IPTOS_LOWDELAY minimize
delay 0x10
IPTOS THROUGHPUT
maximize
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