How to access 2nd WAN config (different subnet)?

[nord_musician]

Hello everybody.

I got an Asus 68u with two WAN connections, the main WAN comes from the ONT (Verizon Fios) and the backup WAN comes from a LTE modem/router with DHCP server and firewall disabled.

The 68u's IP is 192.168.0.1 and works as DHCP server for my home network. The LTE router's IP is 192.168.8.1. The 68u gets the 192.168.8.2 assigned manually when the failover kicks in. I want to be able to enter the config page for 192.168.8.1 while my IP address is still in the 192.168.0.x subnet.

I know the solution lies within routing tables but I have no idea where to start, what to put in each field.

Thanks in advance for any guidance you can give

 

[kfp]

Put your LTE router in bridge mode and set up dual WAN on 68U.

 

[nord_musician]

I have dual WAN set up already and the LTE router doesn't have a bridge mode but it does let you disabe pretty much everything (dhcp server, firewall, wifi) except for NAT

 

[kfp]

I just reread your post and understand what you’re trying to do.

You just have to set up a virtual interface with a static IP on whichever machine you are trying to access it from.

# ip a add 192.168.8.3/24 dev wl0:0

That’s assuming your network interface is wl0, we are creating an alias (virtual interface) and assigning it a static IP. You should then be able to connect to the LTE modem/router while your main WAN is up.

On Windows it’s a bit messier (and anecdotally connection tends to be unstable because the routing sucks), you’ll have to set the IPs of both subnets statically:
https://www.loadtestingtool.com/help/how-setup-ip.shtml

This method gives you the benefit of not having to modify the route table directly, since these commands would modify it when you set up the IPs.

Alternatively, if you really need all clients in LAN to be able to access the LTE modem then you can directly modify the route table on 68U.

 

[nord_musician]

Thanks.

Yeah, I would totally like any client in the LAN (192.168.0.x) to be able to access 192.168.8.1

 

[kfp]

 route add -net 192.168.8.0 netmask 255.255.255.0 gw 192.168.8.1

 

[nord_musician]

Where should I put that? Console via SSH?

 

[kfp]

Yep, I’m not entirely sure if it will conflict with what the router does when failover kicks in though. Please backup before you test this and restore if you encounter problems.

 

[nord_musician]

I'm guessing that to remove it later I should just replace "add" by "remove" , right?

route remove -net 192.168.8.0 netmask 255.255.255.0 gw 192.168.8.1

 

[kfp]

route del -net 192.168.8.0 netmask 255.255.255.0 gw 192.168.8.1

Use ‘del’.

https://linux.die.net/man/8/route

 

[nord_musician]

Oh ok. Thanks, man!

By the way. Why 192.168.8.0? Does it means the virtual interface would be assigned that address as a client of 192.168.8.1?

 

[kfp]

No, that’s specifying a subnet incombination with ‘netmask’.

This has nothing to do with interfaces, we are manipulating the routing table, which tells the kernel where to send packets for different IPs on different subnets.

 

[nord_musician]

Oh ok, it's just that I think I set the ip pool goes from 192.168.8.1 to 192.168.8.2, but again I disabled the DHCP server anyway