[RADIATOR] Use of Radiator during IP address switch

[Stefan Paetow]

Hi, 

So in the next few months we are moving our Radiator hosts to new IP addresses. It's unfortunately a necessary evil that needs to be done. The first host so far has been easy because it literally only involves an IP change.

The other host(s) will need to remain live and working during the change, so the new host has two NICs with different IP addresses. When we cut over, the old IP address will be registered to the second NIC of the new host. Now I want to ensure that during the cut-over period any traffic will head out on the old IP address. Do I set LocalAddress for this to make sure it defaults to the old IP until such time that we switch the old IP address off, or will Radiator be looking at the BindAddress order to decide which IP it sets as the source? See below for some scenarios.

1. Remote host to old IP -> Radiator sets old IP from destination IP in received packet as origin in forwarded packet

2. Remote host to old IP -> Radiator sets LocalAddress as origin in forwarded packet

3. Remote host to old IP -> Radiator sets first BindAddress entry as origin in forwarded packet

4. Remote host to new IP -> Radiator sets new IP from destination IP in received packet as origin in forwarded packet

5. Remote host to new IP -> Radiator sets LocalAddress as origin in forwarded packet

6. Remote host to new IP -> Radiator sets first BindAddress entry as origin in forwarded packet

7. Remote host to new IP -> Radiator broadcasts two packets to remote host (one with old, one with new)

8. Remote host to either IP -> Radiator lets the wind decide which IP it sends from in forwarded packet?


Some certainty here would be very much appreciated (

With kind regards

Stefan Paetow
Federated Roaming Technical Specialist

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