Diskless Server with Network Image Boot

Question

linux

Introductory: there is a computing cluster (powerful servers with an infiniband network). Compute nodes without disks. The task was to load the OS image on them, deploy it and leave it in RAM. An image based on a specific distribution number (RHEL).
There are two working solutions:
1) root mount goes through nfs. I do not want overhead network costs. RAM for the image is not a pity.
2) irritate the initramfs and manually register the download and deployment of the image with your hands. It's not very pretty and not very portable.

Directions that seem promising:
1) Load the system image in the form of a live cd
2) Load microlinux, which is trusted to boot the main system.

There is a feeling that I missed the simplest and most correct solution to the problem.
Can someone tell me how to make it beautiful?

Answer 1

Make a PXE boot (set up a dedicated boot server))). On the PXE server, deploy your system image
In my experience, this is done once or twice

Answer 2

also look in the direction of systemimager, it was in debian-based distributions, in rpm, most likely, something similar was washed down.

Answer 3

As a rule, the basic Linux kernel does not contain any drivers or utilities needed to connect to the root FS. Therefore, if you do not want to rebuild it, you cannot do without initrd.
The standard initrd contains nothing but the minimum set of drivers and utilities required to connect to the root FS. Therefore, if you do not want to rebuild it, you cannot do without NFS.
RHEL6 uses NFSv4 by default, which caches files on the client side, i.e. if the client has enough RAM, data from the NFS server will be transferred no more than once.
An NFS system image is created like this:
access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Storage_Administration_Guide/diskless-nfs-config.html
If you still want to build your own initrd, look at dracut with the livenet module. It is unlikely that livenet collects exactly what is needed for the cluster nodes, but in the image and likeness of livenet and other modules, you can try to write your own.