Gentoo support was apparently over a year ago and it's probably not coming back. So was Arch linux. That's why I left Digital Ocean for VULTR.
I'll try playing around with kexec, but eventually I'll just do the same.
I mean, implementing completely custom OS images is one thing, that's hard. If I wanted to run a hobbyist OS with a custom filesystem format - that would be hard to support, unless there's some kind of "block access" to hard drive image.
Adding Gentoo or Arch support is easy. Just another Linux. It's pretty much obvious they just don't want it.
I mean, I'm not even going to build it there, that's stupid for a production system. I'll build it in-house and then deploy, it's just that I want to build it myself with the software I like and full optimization.
If it puts an extra strain on the environment, why not just charge more for extra CPU or excessive disk write access? We all know SSDs are expensive :)
Just do a stage 3 install to your liking:
That's what I did to solve "my needing to run Gentoo problem".
I need this too, but I'm using hardened-sources. Can you please explain in more details which OS it's better to choose for droplet, how to overwrite that OS with stage 3 on running system, and, finally, how to "use kexec to boot your custom kernel"?
Pick the old Debian 6.0 x86_64. Complete the entire Gentoo install guide. Install and run Midnight Commander. Use MC to delete all directories/files except for /sys /dev and /mnt. Move contents of /mnt/gentoo to / (root). You have to do a mknod of a file under /dev for init 6 to work or go inside the interface and do a power cycle. You load your custom kexec script in /etc/local.d/ that checks the kernel parameters to know whether to execute kexec to boot your custom kernel or bypass running the script if your custom kernel is already running.
Why would you expect that to work when the scripts aren't written with Gentoo in mind? The maintenance/repair procedures for a Ford F150 aren't going to be the same for a BMW 325i at the Imports Repair Auto Shop.