Finding local IP addresses in Python.

How can I find the local IP address (i.e. 192.168.x.x or 10.0.x.x) in python, preferably with only built-in moduals, I would also like it to be platform independent.

From stackoverflow Unkwntech

• import socket
  socket.gethostbyname(socket.gethostname())
  

  This won't work always (returns 127.0.0.1 on machines having the hostname in /etc/hosts as 127.0.0.1), a paliative would be what gimel shows, use socket.getfqdn() instead. Of course your machine needs a resolvable hostname.

  Jason Baker : One should note that this isn't a platform independent solution. A lot of Linuxes will return 127.0.0.1 as your IP address using this method.

  gimel : A variation: socket.gethostbyname(socket.getfqdn())

  Unkwntech : I am accepting this despite the potential for unreliability.

  Jason R. Coombs : This appears to only return a single IP address. What if the machine has multiple addresses?
  From Vinko Vrsalovic

• I'm afraid there aren't any good platform independent ways to do this other than connecting to another computer and having it send you your IP address. For example: findmyipaddress. Note that this won't work if you need an IP address that's behind NAT unless the computer you're connecting to is behind NAT as well.

  Here's one solution that works in Linux: get the IP address associated with a network interface.

  From Jason Baker

• I just found this but it seems a bit hackish, however they say tried it on *nix and I did on windows and it worked.

  s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
  s.connect(("gmail.com",80))
  print s.getsockname()
  

  This assumes you have an internet access, and that there is no local proxy.

  elzapp : Nice if you have several interfaces on the machine, and needs the one which routes to e.g. gmail.com
  From Unkwntech

• You can use the netifaces module. Just type:

  easy_install netifaces
  

  in your command shell and it will install itself on default Python installation.

  Then you can use it like this:

  from netifaces import interfaces, ifaddresses, AF_INET
  for ifaceName in interfaces():
      addresses = [i['addr'] for i in ifaddresses(ifaceName)[AF_INET]]
      print '%s: %s' % (ifaceName, ', '.join(addresses))
  

  On my computer it printed:

  {45639BDC-1050-46E0-9BE9-075C30DE1FBC}: 192.168.0.100
  {D43A468B-F3AE-4BF9-9391-4863A4500583}: 10.5.9.207

  Author of this module claims it should work on Windows, UNIX and Mac OS X.

  Unkwntech : As stated in the question I want something from the default install, as in no additional installs needed.
  From DzinX

• If you don't want to use external packages and don't want to rely on outside Internet servers, this might help. It's a code sample that I found on Google Code Search and modified to return required information:

  def getIPAddresses():
      from ctypes import Structure, windll, sizeof
      from ctypes import POINTER, byref
      from ctypes import c_ulong, c_uint, c_ubyte, c_char
      MAX_ADAPTER_DESCRIPTION_LENGTH = 128
      MAX_ADAPTER_NAME_LENGTH = 256
      MAX_ADAPTER_ADDRESS_LENGTH = 8
      class IP_ADDR_STRING(Structure):
          pass
      LP_IP_ADDR_STRING = POINTER(IP_ADDR_STRING)
      IP_ADDR_STRING._fields_ = [
          ("next", LP_IP_ADDR_STRING),
          ("ipAddress", c_char * 16),
          ("ipMask", c_char * 16),
          ("context", c_ulong)]
      class IP_ADAPTER_INFO (Structure):
          pass
      LP_IP_ADAPTER_INFO = POINTER(IP_ADAPTER_INFO)
      IP_ADAPTER_INFO._fields_ = [
          ("next", LP_IP_ADAPTER_INFO),
          ("comboIndex", c_ulong),
          ("adapterName", c_char * (MAX_ADAPTER_NAME_LENGTH + 4)),
          ("description", c_char * (MAX_ADAPTER_DESCRIPTION_LENGTH + 4)),
          ("addressLength", c_uint),
          ("address", c_ubyte * MAX_ADAPTER_ADDRESS_LENGTH),
          ("index", c_ulong),
          ("type", c_uint),
          ("dhcpEnabled", c_uint),
          ("currentIpAddress", LP_IP_ADDR_STRING),
          ("ipAddressList", IP_ADDR_STRING),
          ("gatewayList", IP_ADDR_STRING),
          ("dhcpServer", IP_ADDR_STRING),
          ("haveWins", c_uint),
          ("primaryWinsServer", IP_ADDR_STRING),
          ("secondaryWinsServer", IP_ADDR_STRING),
          ("leaseObtained", c_ulong),
          ("leaseExpires", c_ulong)]
      GetAdaptersInfo = windll.iphlpapi.GetAdaptersInfo
      GetAdaptersInfo.restype = c_ulong
      GetAdaptersInfo.argtypes = [LP_IP_ADAPTER_INFO, POINTER(c_ulong)]
      adapterList = (IP_ADAPTER_INFO * 10)()
      buflen = c_ulong(sizeof(adapterList))
      rc = GetAdaptersInfo(byref(adapterList[0]), byref(buflen))
      if rc == 0:
          for a in adapterList:
              adNode = a.ipAddressList
              while True:
                  ipAddr = adNode.ipAddress
                  if ipAddr:
                      yield ipAddr
                  adNode = adNode.next
                  if not adNode:
                      break
  

  Usage:

  >>> for addr in getIPAddresses():
  >>>    print addr
  192.168.0.100
  10.5.9.207
  

  As it relies on windll, this will work only on Windows.

  : The one liner solution above generally works on windows. It's the Linux one that's being a problem.

  Jason R. Coombs : +1 This technique at least attempts to return all addresses on the machine.

  Jason R. Coombs : This script fails on my machine after returning the first address. Error is "AttributeError: 'LP_IP_ADDR_STRING' object has no attribute 'ipAddress'" I suspect it has something to do with the IPv6 address.

  Jason R. Coombs : It turns out the issue is that for anything but the first IP address, the adNode isn't dereferenced. Add one more line to the example in the while loop and it works for me: adNode = adNode.contents
  From DzinX

• import socket
  print([ip for ip in socket.gethostbyname_ex(socket.gethostname())[2] if not ip.startswith("127.")][0])
  

  I'm using this, because one of the computers I was on had an /etc/hosts with duplicate entries and references to itself. socket.gethostbyname() only returns the last entry in /etc/hosts. This solution weeds out the ones starting with "127.". Works with Python 3 and 2.5, possibly other versions too. Does not deal with several network devices or IPv6.

  nornagon : seems to work fine in python 2.5 too :)

  ayaz : Awesome. Thanks.
  From Alexander

• im using following module:

  #!/usr/bin/python
  
  # module for getting the lan ip address of the computer
  
  import os
  
  import socket
  
  if os.name != "nt":
  
      import fcntl
  
      import struct
  
      def get_interface_ip(ifname):
  
       s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
  
       return socket.inet_ntoa(fcntl.ioctl(
  
         s.fileno(),
  
         0x8915,  # SIOCGIFADDR
  
         struct.pack('256s', ifname[:15])
  
        )[20:24])
  
  
  
  def get_lan_ip():
  
      ip = socket.gethostbyname(socket.gethostname())
  
      if ip.startswith("127.") and os.name != "nt":
  
       interfaces = ["eth0","eth1","eth2","wlan0","wlan1","wifi0","ath0","ath1","ppp0"]
  
       for ifname in interfaces:
  
        try:
  
         ip = get_interface_ip(ifname)
  
         break;
  
        except IOError:
  
         pass
  
      return ip
  

  Tested with windows and linux (and doesnt require additional modules for those) intended for use on systems which are in a single LAN.

  From smerlin

• FYI I can verify that the method:

  import socket
  addr = socket.gethostbyname(socket.gethostname())
  

  Works in OS X (10.6,10.5), Windows XP, and on a well administered RHEL department server. It did not work on a very minimal CentOS VM that I just do some kernel hacking on. So for that instance you can just check for a 127.0.0.1 address and in that case do the following:

  if addr == "127.0.0.1":
       import commands
       output = commands.getoutput("/sbin/ifconfig")
       addr = parseaddress(output)
  

  And then parse the ip address from the output. It should be noted that ifconfig is not in a normal user's PATH by default and that is why I give the full path in the command. I hope this helps.

  From gavaletz

• I use this on my ubuntu machines:

  import commands
  commands.getoutput("ifconfig").split("\n")[1].split()[1][5:]
  

  From synapz