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content/blog/ipaddressesinpython.md

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+---
+title: "How to get list of IP Addresses in Python"
+date: 2020-09-07T20:03:24-04:00
+draft: false
+tags: ["python", "networking"]
+---
+
+[Elemag](https://stackoverflow.com/users/2436840/elemag) on gave a quick solution on StackOverflow on [how to determine IP addresses with multiple NICS](https://stackoverflow.com/questions/270745/how-do-i-determine-all-of-my-ip-addresses-when-i-have-multiple-nics).  
+
+His one-line solution:
+
+```python
+import netifaces
+ip_addresses = [netifaces.ifaddresses(iface)[netifaces.AF_INET][0]['addr'] for iface in netifaces.interfaces() if netifaces.AF_INET in netifaces.ifaddresses(iface)]
+```
+
+Expanded out to see what is happening
+
+```python
+import netifaces
+interface_list = netifaces.interfaces()
+# Get addresses, netmask, etc. information 
+address_entries = (netifaces.ifaddresses(iface) for iface in interface_list)
+# Only pay attention to ipv4 address types
+ipv4_address_entries = (address[netifaces.AF_INET] for address in address_entries if netifaces.AF_INET in address)
+# Since multiple addresses can be associated, only look at the first ip address
+ipv4_addresses = [address[0]['addr'] for address in ipv4_address_entries]
+```
+
+We can easily adjust this to ask for IPv6 addresses by using `netifaces.AF_INET6` instead.
+
+```python
+import netifaces
+interface_list = netifaces.interfaces()
+# Get addresses, netmask, etc. information 
+address_entries = (netifaces.ifaddresses(iface) for iface in interface_list)
+# Only pay attention to ipv6 address types
+ipv6_address_entries = (address[netifaces.AF_INET6] for address in address_entries if netifaces.AF_INET6 in address)
+# Since multiple addresses can be associated, only look at the first ip address
+ipv6_addresses = [address[0]['addr'] for address in ipv6_address_entries]
+```
+