Telus fiber IPv6 prefix changes every time my router reboots

[JHerbY2K]

Hi all, I have Telus Fiber at home. I'm a pretty advanced user, running both IPv4 and IPv6 via prefix delegation. Works great, except that every time I reboot my router (every few months for an update) i pull a new IPv6 prefix. Any idea why? I have about 10 things to change every time it happens, since Ipv6 addresses are used internally and some of my devices need a static config for various esoteric reasons. it's annoying! My IPv4 address doesn't change - why are IPv6 prefixes not sticky? I'm not asking for garanteed static behavior on a home connection - just trying to understand why they don't persist even a little bit.

I'm using a Unifi Dream Machine Pro connected directly via SFP to Telus fiber. No Telus router involved.

[korrinas4]

Many ISPs assign IPv6 prefixes dynamically to residential customers. This means that each time you reconnect to the network (e.g., after a router reboot), you may receive a new prefix. This is a common practice to manage address allocation efficiently. IPv6 is designed to provide a large number of addresses, and ISPs may not prioritize static address assignments for residential customers. They might assume that most residential users don't need static IPv6 addresses.

[JHerbY2K]

This is not proper behaviour per https://tools.ietf.org/html/rfc8978. In the event that a router reboots (or there is a power outage etc) then clients will have unroutable ipv6 addresses for some time. Telus should change this.

[Kent2]

Can you use unique local addresses (ULA) instead of the GUA? If so that would solve the problem as they are under your control. The disadvantage is that you have to use the numerical values of the address.