Bug #5726
closed
Dyndns updated with wrong IP (PPPoE and transparent ISP proxy)
0%
Description
running 2.2.3-RELEASE (amd64) Jun 23 16:37:42 CDT 2015 .
WAN is a PPPoE. (direct ethernet into pfsense box) DynDNS service is with NoIP.com (free account)
Situation:
WAN IP: 100.78.X.X
external IP check: 94.21.X.X
NoIP updated to: 94.21.X.X
The ISP is most likely using transparent caching proxies but no official statement is available.
The Custom settings for the Dyndns Service give the same result as it falls back to the external IP check.
Issue persist on the 2.2.6 version as well.
"Allow DNS server list to be overridden by DHCP/PPP on WAN" is checked
Updated by Chris Buechler over 9 years ago
- Status changed from New to Not a Bug
- Target version deleted (
2.3) - Affected Version deleted (
2.2.3)
You aren't getting a public IP assigned (100.78 is CGN space), so by design, the public IP used for Internet access is obtained and the registration updated using it.
Updated by Phillip Davis over 9 years ago
Note: CGN space is 100.64.0.0/10 = 100.64.0.0 to 100.127.255.255
Those addresses cannot be routed to on the public internet. So if your ISP is allocating you a CGN address, then there is no point in you setting any dynamic DNS name to translate to that address. Also usually there is also no point setting the dynamic DNS name to translate to the ultimate public IP address that the ISP is using in front of their CGN - that public IP address is being shared by many customers hidden behind the CGN!
To workaround, you would have to get your ISP to setup some port forwards for you from their public-facing IP address in to the CGN address that they provide you. Of course that is not likely to happen, e.g. they can only forward port 80 of that public-facing IP address in to 1 of their customers inside the CGN.
If you need to offer externally-accessible services then you need the ISP to give you a real public IP address.