How is Network interface number enumerated? How to force IF number to stay the same

[Swefred]

Hi

Background

I have an application that depends on being able to communicate with a specific interface card defined in a config file looking like below, %8 specifies Interface number


<ipv6addresses>
<address>de70::6aab:10.1.1.41%8</address>
<address>de70::6aab:10.1.1.42%8</address>
<address>de70::6aab:10.1.1.43%8</address>
<address>de70::6aab:10.1.1.44%8</address>
</ipv6addresses>


My interfaces (route print)


Interface List

6aab...94 f1 <redacted> ......QLogic BCM57810 10 Gigabit Ethernet #8

13...94 f1 <redacted> ......QLogic BCM57810 10 Gigabit Ethernet #9

10...94 f1 <redacted> ......QLogic BCM57810 10 Gigabit Ethernet #0

22...94 f1 <redacted> ......QLogic BCM57810 10 Gigabit Ethernet #7

19...94 18 <redacted> ......Intel(R) I350 Gigabit Network Connection #2

12...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter <- MUST ALWAYS BE THIS INTERFACE

1...........................Software Loopback Interface 1

2...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #2

8...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #3

18...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #4

5...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #5

My problem is that recently the interface numbers changed making the config file setting invalid and the application stopped working. I was told it happened after the application crashed.

Temporary solution:
Solving the problem for now was easy, update the xml file by changing %8 to %12 and start the services related to the application started as it should.


Looking for a permanent solution

Is there a way to force windows to keep the same interface numbers?

Also what decide what number an interface gets?

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