I have a multi processor Redhat 7.3 machine currently doing some heavy media encoding, and another machine identical to it that I would like to also help in this process. Is there an easy way to create a floppy, and NFS boot the second machine? I have enough space on the first machine to duplicate the root directory, and this would be easier then locating another spare hard disk to boot the second machine. It would also elliminate the need to recompile the enitre media encoding programs on the second machine.

I know how to do all the necessary NFS exports, I just don't know how to make a Linux boot disk off my inital install that is more then a rescue disk.

http://www.tldp.org/HOWTO/Diskless-root-NFS-HOWTO-4.html#ss4.1

Of course, if you had a real computer, it would be as easy as typing ``boot net''.

You can dd an NFS-root-booting kernel straight to a floppy, you don't need a distro bootdisk. Or do a Google search for PXELINUX -- you may be able to diskless-boot Linux straight from your BIOS.

Peter

Of course, if you had a real computer, it would be as easy as typing ``boot net''.

I'm assuming this is very similar to the network booting any Open Firmware Mac can do. I personally have never looked in detail at it, how different is this method compaired to PXE? PXE to me is simply a way to take the physical floppy out of the picture, and nothing more. Does net boot do something beyond that?

Fair enough. I forgot about PXE, never having used it. That said, I've never used PXE, so I don't know how it works.

Sun machines' ``boot net'' feature deals with bootp (or also DHCP in newer machines) to get an IP address, etc. It then can parse that information, possibly in combination with responses from a bootparam server, to boot anything you want. It even downloads the initial kernel from the server.

I think that PXE requires that you have a bootable image burned onto the ROM (but I could obviously be wrong). The Sun approach, though, is built into the hardware and requires absolutely nothing more than a computer onto which you can enter commands (it notably does not require an OS or even a hard drive).

Mac Open Firmware is exactly the same thing that's been in Suns for many moons (I forget how long, but it's been at least 10 years), soI bet that they can do the same thing, although I've not tried. In fact, Open Firmware is an IEEE spec now.

Sun machines' ``boot net'' feature deals with bootp (or also DHCP in newer machines) to get an IP address, etc. It then can parse that information, possibly in combination with responses from a bootparam server, to boot anything you want. It even downloads the initial kernel from the server.

I'm not sure what a "bootparam server" is, but everything else you've said there applies to PXE too. You don't have to burn a special ROM, that's the whole point: PXE is a generic client "boot ROM" that can boot anything. Of course, only motherboards with onboard Ethernet tend to come with PXE -- if your network card is a, er, card, then you'd need to blow a ROM for it anyway.

In an unscientific sample size of 2, it seems that all recent motherboards with built-in Ethernet (Spacewalker Athlon thing and Supermicro 370DE6, i.e. pretty much opposite ends of the spectrum) also support PXE.

Peter

In reply to:

---

Mac Open Firmware is exactly the same thing that's been in Suns for many moons (I forget how long, but it's been at least 10 years), soI bet that they can do the same thing, although I've not tried.

---

Macs have used open firmware since at least the first PowerPC machines (circa 1994). However, according to apple the first netbootable ones where the original iMac and iBook (circa 1998). Old NeXT hardware is netbootable as well, all the way back to the original cube. I don't recall if they used OF as well or something else.

-Mike

Another idea might be a bootable cd burned with an entire linux distro on it like this one.

I just used this today in order to backup an entire HD off of a hosed win2k laptop. Worked like a charm. Found all the hardware (nic, sound, modem, usb, video). That distro is basically a scaled down version of Redhat 7.3.

Basically, bootparam provides most of the features missing in BootP that were included in DHCP. That is, the ability to tell the client a variety of useful pieces of information, like NFS roots, default gateways, etc. It's pretty much been superseded by just using DHCP.

Seems like PCs are finally catching up to cutting-edge 1984 technology.