Posted: Sun Feb 27, 2022 19:15 Post subject: My public IP address wrong on the WAN page
My Linksys WRT1200AC router is behind the ISP's modem which is in bridge mode and my router operating mode is set to Gateway. I am running version 48425 DD-WRT firmware. Looking at the Status/WAN page of my DD-WRT control panel, I can see the following:
However, my public IP address is presently 213.149.xxx.xxx and I can access both the router itself and the NAS on my network from the internet side using the 213.149.xxx.xxx address.
So, what are the 100.125.xxx.xxx addresses I see on the Status/WAN page?
Something doesn't add up here. Yes, 100.125.x.x is CGNAT, but that's NOT remotely accessible. Not if your ISP provided modem+router has been bridged, and you have 100.125.x.x assigned on your router's WAN. When using CGNAT you don't have a public IP at all!
Thanks a lot for your kind replies. To clarify: I can NOT access 100.125.x.x remotely, but YES the 213.149.x.x. address. That latter address (which I in my ignorance call "public") I was able to find using three different methods:
1. going to https://whatismyipaddress.com/
2. using my Synology NAS control panel DDNS info
3. reading the response in the DD-WRT control panel's Setup/DDNS status listing when connecting to an external DDNS service (in my case No-IP.com)
Now, after your kind pointing me to the CGNAT info, I am still puzzled how come that apparently I have both a public IP and CGNAT.
Now, after your kind pointing me to the CGNAT info, I am still puzzled how come that apparently I have both a public IP and CGNAT.
Everyone always has a public IP. That's what you see when using something like ipchicken.com. Otherwise your primary router couldn't be addressed from the internet. That's the not the issue.
The problem comes when your DD-WRT router has been assigned a *private* CGNAT ip address on the WAN by your ISP, and *they* are controlling the public IP upstream. You can only port forward using the public IP, and only when assigned to your router.
Thanks again for your kind help. As I wrote in my original post, the ISP's modem is in bridge mode.
You said "...something is amiss here in the OP's description. Either your WAN has a public IP or CGNAT ...it can't be both. When using CGNAT you don't have a public IP at all!"
But now you state that "Everyone always has a public IP".
So, does my DD-WRT router have a public IP "always" or only when there is no CGNAT? Because it appears to me that I have both. That's what puzzles me. Please forgive my ignorance; as you can see by my status, I am a novice
If you use CGNAT, then you defacto do not have your own public IP address.
What you see on "whatismyipaddress.com" is the public IP address of your internet service provider.
Exactly the same IP address can be seen by 1000 other customers.
