Thinkbroadband monitor for changing IP

I'm trying to monitor my home broadband with a Thinkbroadband monitor, but my IP address changes about every 24 hours. They say they support hostnames but I don't know how if my home router has a hostname or how to find it.
Is there any way I can keep my monitor working without manually updating my IP every day?

Try changeip.com You might need something running on a raspberry pi to keep updating it. I run something on my Opnesense router. There are similar services on other routers. Not all are free.

Alternatively Plusent Plusnet made a one time charge of £5 for a fixed IP address.

Most modern routers support DDNS (Dynamic DNS) you can use free providers like changeip.com, dyndns.org, no-ip.com etc. Or if your device supports OpenWRT you could always install that I guess which also has DDNS support.

If your router does not support DDNS their are clients you can install on devices like the Raspberry Pi Zero (cheapest Pi I could find).

Not adding any solutions here, but very curious as to why the IP address changes every 24 hours? That is a new one on me.
My BT one does change but not that often, and the VM one was practically static.

Thanks for the responses. I looked into DDNS on my router and it is supported. I'm on Community Fibre and have their Linksys WHW03CFv2. Under Security > Apps and Gaming there's the options to use DDNS with either dyn.com or no-ip.com. I'll see if that helps. It looks like dyn.com only offers 30 hostnames for $55 a year. NO-IP has a free, single hostname option. That says it uses ads on redirects, which may or may not mess with the Thinkbroadband monitor. Guess I'll have to give it a try.

Bein using no-ip free for years with no issue

In reply to a post by leftyfax:

Thanks for the responses. I looked into DDNS on my router and it is supported. I'm on Community Fibre and have their Linksys WHW03CFv2. Under Security > Apps and Gaming there's the options to use DDNS with either dyn.com or no-ip.com. I'll see if that helps. It looks like dyn.com only offers 30 hostnames for $55 a year. NO-IP has a free, single hostname option. That says it uses ads on redirects, which may or may not mess with the Thinkbroadband monitor. Guess I'll have to give it a try.

Don't Community Fibre use CGNAT? If so, that IP the monitor is pinging is not yours.

In reply to a post by Eeeps:

Don't Community Fibre use CGNAT? If so, that IP the monitor is pinging is not yours.

I've heard other people say that, but I don't understand what it means. Does it mean my monitor is effectively showing some shared node? All I know is, both Thinkbroadband and whatismyip.com return an IPv6 address for me, and it seems to change a lot.

Edit I talked [censored] here - no sleep for 48 hours.

If your router's external IP address is in the range of 100.64.0.0/10 ie begins 100.64. through 100.127. then you are on CGNAT.

To explain CGNAT first consider a normal IPv4 connection.

A domestic router will be allocated a unique IP address. The router provides a private network behind the router with a network range something like 172.16.0.0/24 Millions of domestic installations use the same private network number, private to just them as all communication outside the network is done using the routers allocated public address. The domestic router has to remember which private IP address is expecting what reply so it can translate incoming traffic and pass it on.

Now that there are no new IPv4 addresses to be bought by newer ISPs they have to use IPv6 addresses but IP address ranges cost money. To save money they perform the same Nat process but further up the chain. They allocate a private IPv6 address from that 100.64.0.0/10 range to the outside of your router and all traffic from your router is translated into a unique public IPv6 address further into their network. Unique in that it exists only once on the internet but is being used by multiple customers who all share the same unique IPv6 address.
This means they can use the same private IPv6 address range multiple times across their network. The drawback is that the eventual public IPv6 address is being used by multiple users. A powerful router somewhere on their network is storing information on what traffic is coming from their private network so it can pass back their replies. This results in a small rise in latency which probably goes unnoticed by most users.

Have a look at https://itigic.com/know-if-my-internet-connection-us...

Edited by Moto (Wed 09-Oct-24 21:43:04)

I'm on Community Fibre and had the same problem when TB recognised my IPv6 address, what you need is your IPv4 address and it should only change if there is an outage or they are doing some work on the line, mine has been reporting since 24/09 when they last changed it, I have VOIP via AAISP and they tell me when it changes.

In reply to a post by Moto:

If your router's external IP address is in the range of 100.64.0.0/10 ie begins 100.64. through 100.127. then you are on CGNAT.

To explain CGNAT first consider a normal IPv4 connection.

A domestic router will be allocated a unique IP address. The router provides a private network behind the router with a network range something like 172.16.0.0/24 Millions of domestic installations use the same private network number, private to just them as all communication outside the network is done using the routers allocated public address. The domestic router has to remember which private IP address is expecting what reply so it can translate incoming traffic and pass it on.

Now that there are no new IPv4 addresses to be bought by newer ISPs they have to use IPv6 addresses but IP address ranges cost money. To save money they perform the same Nat process but further up the chain. They allocate a private IPv6 address from that 100.64.0.0/10 range to the outside of your router and all traffic from your router is translated into a unique public IPv6 address further into their network. Unique in that it exists only once on the internet but is being used by multiple customers who all share the same unique IPv6 address.

This means they can use the same private IPv6 address range multiple times across their network. The drawback is that the eventual public IPv6 address is being used by multiple users. A powerful router somewhere on their network is storing information on what traffic is coming from their private network so it can pass back their replies. This results in a small rise in latency which probably goes unnoticed by most users.

If that is right, it is screwed up. The 100.64.0.0/10 range is IPv4, so you cannot allocate an IPv6 address from the range. And the whole point of IPv6 is that there are more than enough addresses to go around without anyone ever sharing. I have available on my network 2^72 IPv6 addresses, all public, compared to 2^32 on the whole internet under IPv4

Nothing of what you describe there has anything to do with IPv6. 100.64.0.0/10 addresses are definitely IPv4.

Thanks for the advice @Moto

Since your message, my external IP abruptly changes to IPv4. The address that was coming up before matches the internal IPv6 address of my laptop. A traceroute to that IPv4 address has a single hop. So it looks like, right now, I'm not on a CGNAT. I possibly was before.

Related, my BQM for my IPv6 address stopped working. I started a parallel one with the new IPv4 address. The quality metrics are night and day. The previous graph was mostly blue and yellow, with packet loss hovering around 5-10%. The new one has a tiny green line at the bottom with no packet loss.

Here's the old BQM from earlier today, looking ropey.

Here's the new BQM, which looks much better.

This coincided with my renewing my contract. I was out of contract on their 40 mbps package (no longer offered) and switched to their 500 mbps one that, bizarrely, is cheaper. Maybe changing the package doesn't just change the bandwidth but the infrastructure too.