Multiple IP addresses – Windows 2008 R2 / Windows 7

Problem:  Source IP address on Windows 7 / 2008 / Vista will always be the lowest numbered IP address on a NIC, no matter what order they are in your NIC configuration.

May cause issues with L2TP VPNs and some firewalls.   IT Support Brisbane

Scenario:
  NIC has multiple addresses:
              10.1.1.1
              172.16.0.1
              192.168.0.1
Source address used for that interface will always be 10.1.1.1  because it is the lowest number, e.g.  10  vs  172.
Resolution:
Need to use  netsh  skipassource  command to get correct functionality.
Show existing skipassource configuration:
netsh int ipv4 show ipaddresses level=verbose
When adding an address that you don’t want to be the source address:
netsh int ipv4 add address “Local Area Connection 3″ 10.1.1.220 skipassource=true
May need these two KB hotfixes:
KB2386184 – Add skipassource functionality to Windows 2008 R2.
KB2554859 – Prevent skipassource flag from being cleared when you use the GUI.

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