Not if you're using AiMesh.
What is there to redo?
To properly add an AiMesh node;
Full reset on the router you want to use as an AiMesh node. Don't touch it any further. On the main router, 'point' to the freshly reset unit and add it as an AiMesh node. Wait for it to reboot.
No option above to 'set' anything.
Sorry, my mistake, reading too fast!
I thought you wanted to specify the IP of the AiMesh node.
I don't use any standard IP ranges for myself or any of my customers. 192.168.1.1, 192.168.50.1, or any other 'default' is not used on purpose.
I would probably 'disconnect' from the GUI the AiMesh node (the RT-AC3100) first and then pull the power cord from it.
Go to the main router and set the LAN IP you want. I would then power down the entire network (modem/ONT, router, switches, and client devices) for the least hiccups going forward for at least two full minutes.
Power up the modem/ONT, wait 5 minutes. Power up the router, wait 5 minutes. Power up the rest of the network infrastructure (switches, etc.), wait 5 minutes.
Now, power up all wired client devices (as fast as you can turn them on).
The network should be working normally now.
Do a WPS reset on the RT-AC3100 and then 'point' to it from the main router to add it as an AiMesh node.
You can use the 'traditional' IP, but better, use one that only you would know.
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