How nodes select gateways?
I would like to use multiple gateways and pair these to specific nodes.
How can i pair nodes and gateways?
I use ethernet gateway (uno+w5100)
@Tommas there can only be one gateway per MySensors network. So you'll need to put the nodes on different networks.
See https://www.mysensors.org/about/network for more info on how nodes, gateways and networks work.
How to set change the channel depends on which transport you are using. Look for the channel setting in MyConfig.h. All nodes in one MySensors network must use the same channel.