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IPv6 and CGNAT – how do we future-proof remote Flex access?

Hi all,
I’ve been running my Flex remote for a while and hit a wall with CGNAT. Some of you probably know the drill, SmartLink just doesn’t work in that situation since the client can’t reach the radio directly. Flex has a helpdesk article on it: link here
Sure, there are workarounds:
- SoftEther VPNAzure from a Pi or other device on the LAN, it does connect, but adds complexity and latency, sometimes enough to make SmartSDR unhappy.
- ZeroTier at layer-2, which some report as working fine with reasonable latency and low packet loss.
In my own case, I ended up paying extra every month just to get a public IPv4 address for my remote QTH so I could avoid CGNAT. It works, but honestly it feels like money spent on a patch for a problem that shouldn’t exist if the radio supported IPv6.
Here’s the bigger picture:
- CGNAT is getting more and more common, especially on mobile ISPs and satellite like Starlink.
- Public IPv4 addresses are scarce and in many cases you have to pay extra to even get one.
- IPv6 often just works, even when IPv4 is broken. I’ve seen this firsthand, my remote site was still reachable over IPv6 while the v4 side was dead.
- Yet Flex gear today doesn’t really speak IPv6.
I’m not saying SmartLink is bad, it’s a good service, but being 100 % dependent on it and IPv4 feels fragile. A bit of IPv6 support would open the door to more direct, simpler setups for remote operation and make the radios more future-proof.
So, questions for the group:
- Anyone here already using IPv6 with a Flex, even if only via VPN or special configs?
- Have you also run into situations where IPv4 failed but IPv6 saved the day?
- Would you also like to see Flex consider at least basic IPv6 support?
I’d love to hear other experiences. Maybe together we can put together a summary of the common pain points (CGNAT, latency, VPN options) and show Flex that this isn’t just a niche request.
73,
Mikel
Comments
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Like you, I'm a huge fan of IPv6! And I wish I could use IPv6 with my Flex 6400.
I ran an IPv6 tunnel for many years in the 20-teens, and it worked beautifully up until Netflix decided I was a criminal 😯
These days, my ISP provides native IPv6. I can simply access any IPv6 service on my home-LAN, from web-serving to logging-database to cloud-storage to my Plex server.
I add my voice to your wish for Flex to embrace and support IPv6 connections to the radios.
1 -
Follow-up
I’m a bit surprised that this thread hasn’t triggered more replies. Maybe it’s because many of you in North America still get public IPv4 as standard and haven’t had to deal with CGNAT yet.
But outside the US, things look different. In Europe, mobile ISPs and even some fiber providers already use CGNAT by default, and in some cases you have to pay extra every month just to get a public IPv4. That’s my situation, and it feels like throwing money at a legacy problem.
IPv6 is not just “nice to have” – in many regions it’s already the only reliable way to reach devices remotely without hassle.
So I’m curious: are we really just a handful of Flex users worldwide that see IPv6 as a must-have for the future, or is this simply not on most people’s radar yet?
0 -
Hello Mikel,
Like you I have to pay extra each month for a static IPv4 address to avoid my ISPs CGNAT. My ISP does support IPv6 and from looking at my router logs the majority of my standard internet access now uses IPv6, much higher percentage than only a year or two ago.
So yes, I am rather surprised that my 8600 and Maestro don't support IPv6, especially as they appear to use operating systems that I would expect to support v6 out of the box. I suspect its been disabled because the discovery and SmartLink protocols haven't been updated for IPv6 yet?
I guess it isn't seen as a priority with all the other work on Aurora etc, but I would certainly like to see IPv6 support.
Best 73,
Jonathan G4IVV0
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