1subnetcalc(1) BSD General Commands Manual subnetcalc(1)
2
4 subnetcalc — IPv4/IPv6 Subnet Calculator
5
7 subnetcalc [Address] [Netmask/Prefix] [-n] [-uniquelocal]
8 [-uniquelocalhq] [-nocolour|-nocolor]
9
11 subnetcalc is an IPv4/IPv6 subnet address calculator. For given IPv4 or
12 IPv6 address and netmask or prefix length, it calculates network address,
13 broadcast address, maximum number of hosts and host address range. Also,
14 it prints the addresses in binary format for better understandability.
15 Furthermore, it prints useful information on specific address types (e.g.
16 type, scope, interface ID, etc.).
17
19 The following arguments have to be provided:
20
21 Address
22 The IP address. If a hostname is provided here, it is tried to
23 resolve the address by a DNS server and the first returned
24 address is used. Internationalized Domain Names (IDN) are sup‐
25 ported.
26
27 Netmask/Prefix
28 The netmask or prefix length (0-32 for IPv4; 0-128 for IPv6).
29
30 -n Skip trying a reverse DNS lookup.
31
32 -uniquelocal
33 Given an IPv6 address, the first 48 bits of the address are
34 replaced by a randomly chosen IPv6 Unique Local prefix in
35 fc00::/7 (see also RFC 4193). Under Linux, /dev/urandom is used
36 for random number generation.
37
38 -uniquelocalhq
39 Like -uniquelocal, but using /dev/random instead on Linux systems
40 for highest-quality random number generation. On other systems,
41 this option is equal to -uniquelocal. Note, that reading from
42 /dev/random may take some time. You can speed up this process by
43 delivering random input e.g. by pressing keys or moving the
44 mouse.
45
46 -nocolour|-nocolor
47 Turns colourised output off.
48
50 subnetcalc 132.252.250.0 255.255.255.0
51
52 subnetcalc 132.252.250.0/255.255.255.0 -nocolor
53
54 subnetcalc 132.252.250.0 24
55
56 subnetcalc 132.252.250.0/24 -nocolour
57
58 subnetcalc fec0:2345:6789:1111:221:6aff:fe0b:2674 56
59
60 subnetcalc 2a00:1450:8007::69 64
61
62 subnetcalc ff08::1:2:3
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64 subnetcalc 131.220.6.5/24
65
66 subnetcalc 132.252.181.87 -n
67
68 subnetcalc www.iem.uni-due.de 24
69
70 subnetcalc www.six.heise.de
71
72 subnetcalc fd00:: 64 -uniquelocal
73
74 subnetcalc fd00::9876:256:7bff:fe1b:3255 56 -uniquelocalhq
75
76 subnetcalc düsseldorf.de 28
77
78 subnetcalc www.köln.de
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80 subnetcalc räksmörgås.josefsson.org 24
81
83 Thomas Dreibholz
84 https://www.uni-due.de/~be0001/subnetcalc
85 mailto://dreibh@iem.uni-due.de
86
87subnetcalc July 24, 2014 subnetcalc