Hi. I have 2 devices. One is my laptop, and other is my raspberry pi.
Currently, my laptop has an ip 100.87.13.90 and my pi has 100.111.253.103.
The machine name of my pi that shows on tailscale is raspberrypi
I looked around to see if it was possible to change the ips.
I found this in the documentation: Network access controls (ACLs) · Tailscale
So I edited my ACL accordingly:
I believe the “hosts” section is for creating aliases for use in your ACLs and not for actually assigning IP addresses to specific hosts.
So in your example, you’re not assigning the machine “raspberrypi” to the address 100.100.100.105, but are saying “If I create an ACL rule which includes the name ‘raspberrypi’ then assume that means the IP 100.100.100.105”. Think of it as a way to make your ACLs easier to read and understand. So you could add a rule to the ACLs list which says like:
And it would allow all members access to 100.100.100.105 on port 53. This gets really handy when you have multiple things you want to allow access to in a single ACL. So if you had multiple rPis, you could make the dst [“raspberrypi:53”, “raspberrypi1:53”, “raspberrypi2:53”] and when you go back to look at it later it makes a lot more sense
Edit: To actually answer your question: I am not sure you can, nor should you need to. With MagicDNS to give friendly names and tags/groups/hosts for ACLs it shouldn’t really matter what internal IP a host gets since it will 1: stay the same for as long as the machine is registered in the tailnet, and 2: be discoverable by the machine’s name in MagicDNS
You’re welcome Also note that you can specify the machine name by changing it in the TailScale client. On linux, it’s the --hostname option you pass to the “tailscale up” command. That will update the machine’s name in your machine list, and it will be reflected in MagicDNS shortly thereafter. You can also do it via the web UI… click the 3 dots in the upper right of machine you want to change, and select “Edit machine name”.
EDIT: Also, just to be clear, the “hosts” bits in the ACL JSON is unrelated to any of this. That is only defining aliases for use in the ACLs themselves and has no bearing or reliance on the machine names in MagicDNS
? Is it not possible to change IPs? What is the 
Also note that you can specify the machine name by changing it in the TailScale client. On linux, it’s the --hostname option you pass to the “tailscale up” command. That will update the machine’s name in your machine list, and it will be reflected in MagicDNS shortly thereafter. You can also do it via the web UI… click the 3 dots in the upper right of machine you want to change, and select “Edit machine name”.