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.
# nping --tcp -c 2 1.1.1.1 -p 100-102
Starting Nping ( https://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
# nping --tcp -c 2 1.1.1.1 2.2.2.2 3.3.3.3 -p 8080
Starting Nping ( https://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
# nping --tcp -c 1 --delay 500ms 1.1.1.1 2.2.2.2 3.3.3.3 -p 137-139
Starting Nping ( https://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
