Hi,

I want to do the following:

CCR = Main Router, connected via PPPoE/DSL as main line
LtAP = LTE-backup

How can I implement that:
- the the CCR checks if DSL is offline and switches over to LtAP automatically
- the LtAP itself should be a normal client and go out via CCR (DSL) unless DSL fails

Is the a guide how to do that? Thanks

You could use OSPF, and set a higher metric on the LtAP.

(both on local route table via pppoe client config, and OSPF)

OSPF metric setup is non obvious (v7)

Part example is:
viewtopic.php?t=181118

Mine wound up as:

/routing filter rule
add chain=ospf-metric rule="if (dst==0.0.0.0/0) {set ospf-ext-metric 20; accept;}"


/routing ospf instance
add disabled=no name=default-v2 originate-default=if-installed out-filter-chain=ospf-metric redistribute=static,vpn,dhcp,modem \
router-id=x.x.x.x