The brute force approach:
from ipaddr import IPv4Network
n = IPv4Network('10.10.128.0/17')
all = list(n.iterhosts()) # will give me all hosts in network
first,last = all[0],all[-1] # first and last IP
I was wondering how I would get the first and last IP address from a CIDR without having to iterate over a potentially very large list to get the first and last element?
I want this so I can then generate a random ip address in this range using something like this:
socket.inet_ntoa(struct.pack('>I', random.randint(int(first),int(last))))
Maybe try netaddr instead, in particular the indexing section.
https://pythonhosted.org/netaddr/tutorial_01.html#indexing
from netaddr import *
import pprint
ip = IPNetwork('10.10.128.0/17')
print "ip.cidr = %s" % ip.cidr
print "ip.first.ip = %s" % ip[0]
print "ip.last.ip = %s" % ip[-1]
Oops...looks like ipaddr module supports this method as well! I should have tried that. I used ipaddr over netaddr as I found the former had more reliable operations for checking overlapping CIDRs.