Installing openSUSE to an external hard drive then boot mac

Hi. I want to install openSUSE on an external hard drive (about 500gb of open space). There’s nothing on there that I want, so reformatting is fine. I was wondering if someone could explain to me how that would work or point me to a how-to. Also, I have a few questions:

  1. If I partitioned the drive (however I would do that, hopefully a How-To will say), will files saved while running openSUSE from that hard drive save to the hard drive?

  2. Will it work with a Mac?

  3. Will I still be able to save files to the unused space of the hard drive?

  4. If it works with a Mac, will it also work with a PC, or is it one or the other?



Installing on an external hard drive (likely an USB one) is not very different of doing it on internal ones. You only have to take special care of selecting the correct device name when yast get to the partition step of the installation process. If it is a USB drive, the name should look something like /dev/sd*.
If you happen to have internal(s) scsi/sata drives, you will see them enumerated like this: /dev/sda, /dev/sdb,…etc.
Identify the external one looking to other properties: UUID, size, etc.

Some points you have to take into account:
-If your machine BIOS support booting from USB, you likely will be interested in installing the linux boot loader, grub, into the MBR of the external hard disk instead of the internal, which is a good thing: every OS and corresponding boot loader in its own disk.
If that is what you want, configure yast to install in one of the first partitions (boot, root) of your new system layout.

Now for the questions:

  1. Once the system is up and running, it will only see those file system mounted at boot time (/etc/fstab) or manually. So, those will be the file system Open Suse will use. In other words, if you want you new system use one of the partitions in the internal hard disk, you will have to tell yast about it at installation time or later, by mounting it manually from the command line or editing the /etc/fstab.

  2. No. If you install an i386 based distro on a i386 machine, the binaries installed in the drive will only run in a 386 machine.

  3. Yes. You only have to create additional partition(s) from the unused space in the disk, build a fs on it and mount on a customized given directory in the root tree hierarchy on your Open Suse system.

  4. Again, if you have installed an 386 based release of linux on the external disk connected to a 386 architecture based machine, you will only be able to boot it in that specific machine.
    Keep in mind that there is fundamental incompatibility issue because of the processor used in a system, but it is also important taking into account that the installation procedure makes a lot of automatic decissions you are almost unaware of depending upon the hardware devices found in the system. So, even between boxes featuring processors in the same architecture family, you can’t happily use that external drive (which hosts a system tunned according to the hardware devices found at installation time) to boot different machine, unless it is 100% hardware identical to that used to install the system.

Finally, what you can do is install two or more systems in the same disk, each one with its own partition layout.