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  • You can tell the dhcp server to only assign a certain ip address to a certain mac in its configuration files. EDIT: you do not want to change any settings on the dhcp server? that would change things Commented May 4, 2023 at 21:15
  • @Cheetaiean I use this in a script that anyone can download. If the users need to modify their router settings only to run my script, that will be too much to ask. So no, I dont know anything about the DHCP servers people will have. I just assumed 99 percent of them will always serve the same IP to the same MAC, because every router I ever owned worked that way. Commented May 4, 2023 at 23:18
  • I'm going to suggest you send raw DHCP packets then. Simply broadcast a DHCPDISCOVER, and then wait for the DHCPOFFER from the server, which will tell you exactly what you need to know. Commented May 4, 2023 at 23:54
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    XY problem? Why do you need the address before the VM gets it? The hypervisor may provide means to see the current address; or to communicate with the VM itself in a way that doesn't depend on networking. Either way learning the actual IP address after the VM gets it may be possible. Commented May 5, 2023 at 0:55
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    If you want the VM to announce its IP address without any guest module requirement you can use LLDP, which is built into systemd. See EmitLLDP= Commented May 5, 2023 at 13:32