I have an odd issues, where when a device restarts DHCPv6 is always giving the client a new IPv6 address.
Within the leave on "ICP DHCPv6" I see the following (attached)
(https://forum.opnsense.org/index.php?action=dlattach;topic=44549.0;attach=40385)
Any idea's the leave times are default?
I'm just guessing, but did you provide the dhcp identifier has "mac address" in your client device?
Not sure what you're using. Under Ubuntu for example you have a tool called netplan (not a fan of it.. but it is what it is). And via netplan I can configure under the correct interface:
dhcp-identifier: mac
So in that case I would expect the DHCPv6 server to identify that it is indeed the same server, since the mac address didn't change?