Multiple flannel_iface

Hello.

Is it possible to add more than one interace to flannel to choose from for custom cluster created in Rancher?
According to flannel documentation, it is possible:
–iface="": interface to use (IP or name) for inter-host communication. Defaults to the interface for the default route on the machine. This can be specified multiple times to check each option in order. Returns the first match found.

How should I edit network part in cluster yaml? Could it be like this?
flannel_iface: eth1,enls8

Or can I change those settings only for specific node?

Thanks. Best regards, Michal