Re: How to detect the IP CAM on LAN from WG tunnel ?

[Nohk Two <nohktwo@gmail.com>]

On 2024/6/21 17:18, Mark Lawrence wrote:
>> How do you solve this problem ?
> 
> Iterative fact checking, from the lowest levels of the network stack to the highest.
> 
>      - Are the devices actually connected where you think they are?
>          - With the tunnel disconnected, does your phone connect to the           camera?
I use wireguard VPN while my phone is using mobile data (4G LTE). With the tunnel disconnected my phone can't connect to the camera since it scanned and cannot find the camera.

>      - Is your Wireguard tunnel set up properly?
>          - Can your phone ping the wg0 address with the tunnel active?
>          - Can your phone ping other .100 devices with the tunnel           active?
I don't know how to ping from my phone. But the phone, with the wireguard tunnel connected, can visit my LAN website which is in the network 192.168.100.0/24.

>      - Does your eth0/wg0 machine have IP forwarding enabled?
>          - sysctl net.ipv4.ip_forward=1
Yes.
$ sysctl net.ipv4.ip_forward
net.ipv4.ip_forward = 1

>      - What does packet tracing show?
>          - I.e. `ngrep -d wg0 .\* icmp` or the tcpdump equivalent, also           against eth0 for the wireguard UDP port.
I use `ngrep -d wg0 .\* icmp`, but nothing dump. However while I open my phone's browser to visit my LAN site, it did dump something.

>      - Does the mobile App actually support remote (routed) cameras or       just on the local network?
> 
This is the point I said in my original mail that I think my phone and the camera are in different networks. I believe this App is for LAN network.

For this scenario, are there solutions ?