split_supernet_into_classful_subnets_for_rdns_zone_creation-2.sh

#! /usr/bin/env bash

###
#
# Example input 100.64/10 -> 100.64.0.0 255.192.0.0
#
# Split into /24's -> cidr 255.255.0.0
# Split into /16's -> cidr 255.255.255.0
#
# Replace cidr with relavant value, if splitting on non-classful boundaries
#
# Note:
# Depending on if you experience the output does not output the fill list, it could
# be necessary to use a nested loop to get the relevant ranges. If the final item
# count is large enough.
#
###

for supernet in $(

  ipcalc -b 100.64.0.0 255.192.0.0 255.255.0.0 |
  grep -P '^Network' |
  grep -P -o '(\d+\.){3}\d+\/\d+';

); do

  for subnet in $(

    ipcalc -b ${supernet} 255.255.0.0 255.255.255.0 |
    grep -P '^Network' |
    grep -P -o '(\d+\.){3}\d+\/\d+';

  ); do

    echo $subnet;

  done

done

split_supernet_into_classful_subnets_for_rdns_zone_creation.sh

#! /usr/bin/env bash

###
#
# Example input 100.64/10 -> 100.64.0.0 255.192.0.0
#
# Split into /24's -> cidr 255.255.0.0
# Split into /16's -> cidr 255.255.255.0
#
# Replace cidr with relavant value, if splitting on non-classful boundaries
#
###

for subnet in $(

  ipcalc -b 100.64.0.0 255.192.0.0 255.255.0.0 |
  grep -P '^Network' |
  grep -P -o '(\d+\.){3}\d+\/\d+';

); do

  echo $subnet;

done