The other problem with network booting
Following on to NetbootProblems, there's one final problem with using netboot to install machines: everyone does network installs differently. With CD/DVD based installs, you throw the disc in the drive, boot the machine, and follow the installer's directions. With network installs, well, it depends; there is very little commonality on how you get to the 'follow the installer's directions' stage.
This is the real attraction of virtual DVD-ROMs: like the old math joke, they reduce network installs to an already solved problem.
I see at least two reasons the netboot problem persists:
- the only real way to make things common across different environments
is to base network installs on putting ISO images on the network
instead of burning them to CDs, but making reading ISO images off the
network look like reading CDs takes a fair amount of work somewhere
in the installer.
(Linux makes it look somewhat easy, but Linux gets to reuse a bunch of general support, and your remote access protocol needs to look like a filesystem to Linux.)
- we have no common, simple network protocol that is good at (read-only) random access to large files. NFS and SMB/CIFS are not simple, and HTTP is not good at random access (I'm not sure FTP is simple, and it's no better at random access than HTTP).
Thus, unfortunately I suspect that I will be burning CDs and DVDs for quite some time to come. The only bright spot on the horizon is the possibility that service processors that can do virtual DVD drives will become common in the servers we buy.