Starting today, Tailscale users have the ability to control which IP address is assigned to their nodes from the CGNAT range. Previously, Tailscale allocated a unique IP address to each node, but with the increasing popularity of the service, they are running out of IPs. Rather than adding more private IP address ranges or requiring IPv6 addresses, Tailscale has decided to allow the reuse of CGNAT addresses in different tailnets. Additionally, Tailscale is launching a beta feature that lets users define the IP pool for their nodes. This change allows for greater flexibility and compatibility with other systems. Overall, Tailscale is ensuring that addressing remains manageable and efficient for its users.
https://tailscale.com/blog/choose-your-ip/