Nomad
cidrhost Function
cidrhost
calculates a full host IP address for a given host number within
a given IP network address prefix.
cidrhost(prefix, hostnum)
prefix
must be given in CIDR notation, as defined in
RFC 4632 section 3.1.
hostnum
is a whole number that can be represented as a binary integer with
no more than the number of digits remaining in the address after the given
prefix. For more details on how this function interprets CIDR prefixes and
populates host numbers, see the worked example for
cidrsubnet
.
Conventionally host number zero is used to represent the address of the network itself and the host number that would fill all the host bits with binary 1 represents the network's broadcast address. These numbers should generally not be used to identify individual hosts except in unusual situations, such as point-to-point links.
This function accepts both IPv6 and IPv4 prefixes, and the result always uses the same addressing scheme as the given prefix.
Examples
> cidrhost("10.12.127.0/20", 16)
10.12.112.16
> cidrhost("10.12.127.0/20", 268)
10.12.113.12
> cidrhost("fd00:fd12:3456:7890:00a2::/72", 34)
fd00:fd12:3456:7890::22
Related Functions
cidrsubnet
calculates a subnet address under a given network address prefix.