Updating ISP Redundancy Settings

[Wyman]

Hi all. We're changing our backup ISP provider and I want to double check the process for updating the settings on the firewall. I've had a look at the ISP redundancy document and it seems like a simple change from old IP to the new and obviously the physical cable change between the new router to the external switch.

As this is my first time doing this, I just want to see if there will be any less obvious issues. Thanks in advance.