Unlike other ping and packet generation tools, Nping supports
multiple target host and port specifications. While
this provides great flexibility, it is not obvious how Nping handles
situations where there is more than one host and/or more than one
port to send probes to. This section explains how Nping behaves in
these cases.
When multiple target hosts are specified, Nping rotates among them
in round-robin fashion. This gives slow hosts more time to send
their responses before another probe is sent to them. Ports are
also scheduled using round robin. So, unless only one port is
specified, Nping never sends two probes to the same target host and
port consecutively.
The loop around targets is the “inner loop” and the
loop around ports is the “outer loop”. All targets
will be sent a probe for a given port before moving on to the next
port. Between probes, Nping waits a configurable amount of time
called the “inter-probe delay”, which is controlled by
the --delay option. These examples show how it
works.
-
One target, three ports, and two rounds.
# nping --tcp -c 2 1.1.1.1 -p 100-102
Starting Nping ( http://nmap.org/nping )
SENT (0.0210s) TCP 192.168.1.77 > 1.1.1.1:100
SENT (1.0230s) TCP 192.168.1.77 > 1.1.1.1:101
SENT (2.0250s) TCP 192.168.1.77 > 1.1.1.1:102
SENT (3.0280s) TCP 192.168.1.77 > 1.1.1.1:100
SENT (4.0300s) TCP 192.168.1.77 > 1.1.1.1:101
SENT (5.0320s) TCP 192.168.1.77 > 1.1.1.1:102
-
Three targets, one port, and two rounds.
# nping --tcp -c 2 1.1.1.1 2.2.2.2 3.3.3.3 -p 8080
Starting Nping ( http://nmap.org/nping )
SENT (0.0230s) TCP 192.168.0.21 > 1.1.1.1:8080
SENT (1.0240s) TCP 192.168.0.21 > 2.2.2.2:8080
SENT (2.0260s) TCP 192.168.0.21 > 3.3.3.3:8080
SENT (3.0270s) TCP 192.168.0.21 > 1.1.1.1:8080
SENT (4.0290s) TCP 192.168.0.21 > 2.2.2.2:8080
SENT (5.0310s) TCP 192.168.0.21 > 3.3.3.3:8080
-
Three hosts, three ports, one round, inter-probe delay of 500 ms.
# nping --tcp -c 1 --delay 500ms 1.1.1.1 2.2.2.2 3.3.3.3 -p 137-139
Starting Nping ( http://nmap.org/nping )
SENT (0.0230s) TCP 192.168.0.21 > 1.1.1.1:137
SENT (0.5250s) TCP 192.168.0.21 > 2.2.2.2:137
SENT (1.0250s) TCP 192.168.0.21 > 3.3.3.3:137
SENT (1.5280s) TCP 192.168.0.21 > 1.1.1.1:138
SENT (2.0280s) TCP 192.168.0.21 > 2.2.2.2:138
SENT (2.5310s) TCP 192.168.0.21 > 3.3.3.3:138
SENT (3.0300s) TCP 192.168.0.21 > 1.1.1.1:139
SENT (3.5330s) TCP 192.168.0.21 > 2.2.2.2:139
SENT (4.0330s) TCP 192.168.0.21 > 3.3.3.3:139
