How to access my ONT huawei EG8145V5 from router asus rt-ac68u v3?

[StrikerXXX]

Hey guys! My question is the title of the topic, I wanted to know what I need to do for my ac68u v3 to be able to access the ONU in bridge mode.

My ONU is a huawei eg8145v5, it is in bridge mode, the ac68u v3 is doing the pppoe dialing.
I use the official asuswrt, version 3.0.0.4.386_51255, I use the default settings, but I still can't access ONU web gui.

I know there is this alternative solution that works, which would be to run these commands through ssh:

ifconfig eth0:0 192.168.18.2 netmask 255.255.255.0
iptables -t nat -I POSTROUTING -o eth0 -j MASQUERADE

The problem is that I find this a nuisance, having to use these commands whenever you need to access the ONU web gui. Is there any way to configure the official asuswrt and the eg8145v5 to communicate, so I can have access to it whenever I want?

I was informed that the ac68u v3 should access the web gui of the eg8145v5 without any problem, but something is preventing the communication.

In internet status, in the wan ip option, the correct thing would be to show the pppoe connection ip and the ONU ip, correct? This should also happen on both the netmask and the gateway, right?
But the private ip appears here in the wan ip, because I have cgnat and the edge public ip that the provider uses in cgnat, the ONU ip does not appear here instead of the external public ip. Would it be some incorrect configuration in the ac68u or in the ONU?

 

[ColinTaylor]

As per this post try setting your WAN IP manually to 192.168.18.2.

 

[StrikerXXX]

As per this post try setting your WAN IP manually to 192.168.18.2.

Thank you very much, I did this procedure from the link and it worked, thank you for the information!