Can I have multiple motherboards share one hard drive?

Question

Is there a way to share 1 hard drive between multiple motherboards (they will be old ones). I don't need to be able to write, just boot all of them from it.

Answer 1

This will not work.

What you are trying to do has a few problems with it.

1. Have multiple machines controlling the same piece of hardware. While this is possible, it does mean that while OS #1 is using the drive OS #2 may have to wait
2. Generally this is not a big deal, and this is why CD drives for example can be shared over a network. However, an OS cannot just wait like this. In addition, this type of sharing generally has to be done within an OS (server or otherwise)
3. You run into problems where one OS changes the system files that another OS is using. This cannot do anything good.
4. Unless the machines all have the same hardware, all but one of the machines may not boot (or the first machine to boot may crash) since the hardware configuration that is loaded will appear to change when in fact it has not.
5. Perhaps one of the most practical considerations, there is no hardware that I am aware of that can make this work.

Find another way to do this (use multiple media), or live with using one machine at a time.

Answer 2

If they're networked together, sure. But there will be one machine that has the hard drive physically connected to it that will have to boot first. The others can boot using PXE and iSCSI or NFS. Basically, one machine will act as a NAS server and the rest will network boot.

Answer 3

This may work:

1. You'll have to share this hard disk from a separate computer or network appliance using iSCSI protocol. This can be a general-purpose computer (running Linux, for example), or an appliance running something like FreeNAS.

2. Your computers' hardware must support booting from iSCSI disks. While many OSes support iSCSI once it's booted up, for initial booting network-card support is needed. I've never heard of a consumer-level motherboards or network cards that support it.

3. Your OS must support booting from a read-only media. You probably can do this with a Linux or other unix-based system, but I don't think you can do this with Windows (although Windows 3.11 supported this many years ago).

4. Your computers must have a very close hardware configuration, and you must insure that all "unique" data is ether dynamic (you cannot have static IPs obviously), or supplied via some other mechanism.

In conclusion: can be done in theory, but in practice it's much easier to and cheaper to just get a second disk.

Answer 4

This is worth looking at - its a very similar setup to what you want, but if you wanted a set of systems running off a single hard drive with persistant installs. There's far too much detail for me to repost it, but to sum it up

If you're running linux, he's used nbd to export the root disk images, and uses optional COW layers for the persistant parts of the set up.You will also need a dhcp server and the ability to use TFTP

He's also used iscsi for windows boot, though that needed fpxe images for his network card.

Another approach you could take is to use ltsp, and boot the client systems as dumb terminals