IIRC, when you disable dhcp on the network, modern cloud-init (like debian 12/Ubuntu 22.04) will configure the IP on your instance at boot time after doing a metadata network request.
That just works, but it depends on OS.
Cheers,
Arnaud
Le 11 août 2023 04:43:42 GMT+02:00, "Nguyễn Hữu Khôi" <nguyenhuukhoinw@gmail.com> a écrit :
Yes. I agree with you but when all controller is down and some users need to reboot their instances then it won't have ip. This is my worry.
On Thu, Aug 10, 2023, at 12:00 AM, Nguyễn Hữu Khôi wrote:
> Hello guys.
>
> Sometimes I see that my instances won't get IP from Neutron DHCP Agent.
>
> Is it good if we set a fixed port for instance and set a static ip in
> the instance's netplan configuration also?
We do this for IPv6 addresses on some of our servers as we've had problems with RAs. It seems to work fine in that case. Ideally, this shouldn't be necessary for any cloud instance though and it might be worth digging into why dhcp isn't working so that it can be corrected.
>
>
> Nguyen Huu Khoi