lostpacket
Level 2: Rookie

NBN IPv6 and IPv4 NAT

Hi,

I have been on Telstra NBN fibre to the home for 6 months.

The router would gets an IPv4 address in the 110.151.0.0/16 range. Also a valid IPv6 /56 prefix would be allocated.

I used dynamic dns to allow VPN and ssh acces to the home network ( File server and security cams ).

 

Yesterday ( 3/10/2107) the router could not renew the DHCP lease, and shortly after, obtained a new address in a

range that appears to have an address translation layer applied.

 

The router reports its external address is 100.80.1.250

The IP address at IP test sites for dynamic dns appears as 103.217.166.34

There is no IPv6 prefix allocated.

 

This has broken dynamic dns, and the ability to VPN or ssh into my router, and home network.

 

Why has it changed, and will it return to its former functionality.

 

Thanks

Was this helpful?

  • Yes it was, thank you
  • No, I still need help
4 REPLIES 4
cf4
Level 25: The Singularity
Level 25: The Singularity

Re: NBN IPv6 and IPv4 NAT

Have you checked what address is displayed on this ste https://www.yougetsignal.com/tools/open-ports/

lostpacket
Level 2: Rookie

Re: NBN IPv6 and IPv4 NAT

 

The address  at https://www.yougetsignal.com/tools/open-ports/https://www.yougetsignal.com/tools/open-ports/ is 103.217.166.34.

 

A more interesting thing is that my router ( IP 100.80.1.250 ) is not available for incoming ssh on port 22.

This is also confirmed by the blacklist file on the router for failed ssh login attempts, there have been no new entries since yesterday, and its normally 4-5 a day :-).

 

Why are telstra NATing me, and blocking traffic ???

 

 

lostpacket
Level 2: Rookie

Re: NBN IPv6 and IPv4 NAT

I have found the answer.

At 1:00pm on the 3rd October, NBNco would have moved the D1 ethernet port on the fibre port to a new ISP - Myrepublic.

As there is no authentication, the router just noted that it could not renew its DHCP address lease and had been given a new IP address - 100.80.1.250

 

Myrepublic use Carrier Grade NAT to provide 100 megabit downstream links, which may be good for streaming, but it breaks VPN and SSH connections, as there is no path back to my home equipment. The clue is the IP address is in a range assigned to shared address space for ISPs to use NAT on. ( See RFC6598).

 

So if your router collects an address in the range 100.64.0.0 - 100.127.255.255 your do not have clear internet access.

 

Telstra are having a problem getting the connection switched back, as there does not seem to be a workflow to retrieve a lost customer 🙂

 

 

 

 

 

 

 

 

cf4
Level 25: The Singularity
Level 25: The Singularity

Re: NBN IPv6 and IPv4 NAT

Thanks for that information. I was considering swapping to Myrebulic, I have several IP cameras so will now search for another provider that will guarantee a public IP address.

Set it & forget it

With direct debit there’s no need to give paying your bill another thought.

Avoid queuing up and never worry about late fees again.

Setup direct debit