Another tiny bug with WAN IP address rotation

[Pila]

Apparantly, my router gets confused from time to time, and does not see the Singe NAT USB modem Public WAN IP address after it is rotated by my ISP. Sometimes it gets much worse, as evident in my other posts. Asuswrt-Merlin RT-AC56U_380.59_0

But, this might affect others as the problem may not be so evident: ocassionally, a router assignes private address to the Single NAT modem! So, DDNS updating scripts may try to report this private address for the Single NAT modem. Should your DDNS service select to accept it (instead of reading it on its own), incoming connection will fail.

If it is only happenng when connected to the USB I can not say as I will normally not notice it. My DoubleDDNS script adapts automatically, so I do not care about this problem.

Oct 20 01:12:05 pppd[1349]: Serial connection established.
Oct 20 01:12:05 pppd[1349]: Using interface ppp0
Oct 20 01:12:05 pppd[1349]: Connect: ppp0 <--> /dev/ttyUSB0
Oct 20 01:12:09 pppd[1349]: Could not determine remote IP address: defaulting to 10.64.64.64
Oct 20 01:12:09 pppd[1349]: local  IP address 10.93.199.238
Oct 20 01:12:09 pppd[1349]: remote IP address 10.64.64.64
Oct 20 01:12:09 pppd[1349]: primary   DNS address 212.91.97.4
Oct 20 01:12:09 pppd[1349]: secondary DNS address 212.91.97.3
...
Oct 20 01:12:15 custom script: Running /jffs/scripts/ddns-start (args: 10.93.199.238)
Oct 20 01:12:21 ddns: Completed custom ddns update
Oct 20 01:12:21 nick: DoubleDDNS (good) primary updated to 31.45.225.227
Oct 20 01:13:09 nick: DoubleDDNS (good2) secondary updated to 31.45.225.227

While it may be a bug on the side of my ISP, I suspect Asus router more. So, if you notice your DDNS is not connecting you to your router, it might be worth to check if it points to a private address instead of a public one.

Other than that, I was normally using the Internet with such address. Next rotation was caught by my router normally.

 

[Pila]

Yuo, bug shows itself again. But, if I do not look, I wil not norice.

Again: I have Single NAT modem, how is 10.92.213.255 as WAN IP claim possible? It should not be. A bug.

Oct 24 02:28:45 WAN Connection: WAN was restored.
Oct 24 02:28:45 start_nat_rules: apply the nat_rules(/tmp/nat_rules_ppp0__dev_ttyUSB0)!
Oct 24 02:28:46 rc_service: ip-up 29244:notify_rc start_upnp
Oct 24 02:28:46 rc_service: waitting "stop_upnp" via ip-up ...
Oct 24 02:28:47 custom script: Running /jffs/scripts/ddns-start (args: 10.92.213.255)
Oct 24 02:28:53 ddns: Completed custom ddns update
Oct 24 02:28:53 pila: DoubleDDNS (good) A updated to 31.45.225.106
Oct 24 02:28:55 pila: DoubleDDNS (good2) B updated to 31.45.225.106

 

[tomsk]

Yuo, bug shows itself again. But, if I do not look, I wil not norice.

Again: I have Single NAT modem, how is 10.92.213.255 as WAN IP claim possible? It should not be. A bug.

Oct 24 02:28:45 WAN Connection: WAN was restored.
Oct 24 02:28:45 start_nat_rules: apply the nat_rules(/tmp/nat_rules_ppp0__dev_ttyUSB0)!
Oct 24 02:28:46 rc_service: ip-up 29244:notify_rc start_upnp
Oct 24 02:28:46 rc_service: waitting "stop_upnp" via ip-up ...
Oct 24 02:28:47 custom script: Running /jffs/scripts/ddns-start (args: 10.92.213.255)
Oct 24 02:28:53 ddns: Completed custom ddns update
Oct 24 02:28:53 pila: DoubleDDNS (good) A updated to 31.45.225.106
Oct 24 02:28:55 pila: DoubleDDNS (good2) B updated to 31.45.225.106

This just looks like a private IP address...are you double NATed or your ISP is giving you a private IP?

 

[RMerlin]

It's not unusual for mobile providers to use a 10.x.y.z/24 IP. Mobile networks are intended for outbound traffic, not for requiring inbound service connections, so it allows them to save on IP addresses.

 

[Pila]

My ISP rotates address on a 1-2-3 day basis. It is a Public IP address because this is dedicated 3g data line (not data + voice). For comparison: on my mobile phone, I get private IP address, and that is OK since that line is voice+data. But, as I said, I can not be certain, I will check with them.

But: I assumed there was no problem, and I was wrong. When I tried to connect with VPN, I never reached my router. I was using correct external Public WAN IP my modem was using, while my Router was seeing private 10.x.x.x WAN IP address. Again, I can not be certain of anything, but this is inline with my original problem I posted before.

2 issues exist provoked seemingly by the same action - WAN IP rotation:

1) After my Singe NAT WAN IP address rotates, and my router sees regular Public WAN IP in many cases, I loose routing from inside the network to the Internet. Router itself sees and uses the Internet perfectly well. I can connect from outside with VPN and work normally, get any info from the local network and connect to all devices. I can easily detect anomaly by ssh from router to another device and doing external transfer. This MUST be a router problem. After WAN IP address rotates, we start once again and any behaviour is possible: normal or confused.

2) In some rare cases, my router (for now, this is an assumption) assigns Private WAN IP addres, and then I can not connect externaly to the VPN at all. My WAN IP Public address is always correctly reported at my DDNS service as my script takes care of that, adjusting to the Single and Double NAT on the fly. But, from inside that network, all is perfectly normal. I have no way localy to detect an issue, other than noting Private IP address. Again, after WAN IP address rotates, we start once again and any behaviour is possible: normal or confused.

problem is: for majority of the time, I am accessing this system from outside. Then I can not notice this 2) problem. When locally: if I do not go and check my WAN IP at the router, I will notice nothing. I will now adjust my programming to the problem.