Hi
It's been a long time i didn't do any Arista config.
If you add a 2nd circuit and can do a port-channel, you'll need to setup the ip on the PO instead of physical interface.
If i recall, on Arista, scripting to automate the change is called AEM. You can trigger the script at reboot or after you issued the command no ip address on your physical to tell it to change the config of this interface by adding it to a port-channel and setup the ip. After that, ospf still be back up.
Another solution would be to export the config, modify the file and upload this file to your startup then reboot the device.
No matter which solution, you need to test it before to a close device because there's a risk associated.
I don't have any Arista accessible to make some examples to share, I'm sorry.
Thanks
Francesco
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