#!/bin/bash EXPECTED="table ip x { map y { type ipv4_addr : interval ipv4_addr flags interval elements = { 10.141.10.0/24 : 192.168.2.2-192.168.2.4, 10.141.11.0/24 : 192.168.4.2-192.168.4.3 } } chain y { type nat hook postrouting priority srcnat; policy accept; snat to ip saddr map @y } } " set -e $NFT -f - <<< $EXPECTED $NFT add element x y { 10.141.12.0/24 : 192.168.5.10-192.168.5.20 }