rala wrote theoretical both use the same provider and I was also thinking about giving the SIM from the new in the old device. @rala If both SIM cards belong to the same provider give it a go before...

@rala Your ISP router is probably locked (see this thread - https://forum.openwrt.org/t/unlocking-huawei-ha35-22-hybrid-modem-dsl-lte/34302). That's the reason for disabled options that you see in...

@rala OK. So you have an old ISP router in 10.x.x.x subent. Is it 3G/4G router as well, it's a DSL modem router or just a wireless router ? What's the make and model ? You have a new MR600 in...

@rala Let me explain in details. For example: If your main router is with LAN IP address 192.168.0.1 its DHCP server will serve IP addresses in 192.168.0.0/24 subnet. If your old ISP router is with...

@rala Disabling DHCP server on the old ISP router is mandatory to be able to work as an access point. Sometimes there's an option to use an external DHCP server where you can point to MR600 IP...

@NCFL To use both MR200 in a failover scenario you'll need an additional hardware like these load balancers. Here's an example configuring the load balancer.