I have been trying to install Linux onto an IDE hard drive I put into an external enclosure that already has Fedora 14 installed on it but I keep getting the problem of not being able to find a bootable volume. I have so far tried Ubuntu 11.04, Ubuntu 11.10, and Fedora 16 with all of them being of the 64-bit flavor. I'm doing this on my desktop where I have disconnected the data cable to the internal drives to prevent any changes to the boot sector.
Any suggestions on how to get past this problem? Do I take the drive out of the enclosure and put it internal? Because I have already installed a now older distribution onto it so I don't understand why it is not working.
You need to ensure that the motherboard of the machine supports booting from USB devices (which there are a few variations a la USB optical, USB floppy, and USB hdd) and that it's configured to do so.
IDE <-> USB is going to incur some overhead, so as amdfangirl noted, there will be a performance hit (for an IDE class device, which likely tops out around 50-60 MBps, this may not be overly painful but it will still be overhead)
Ok, so you can boot to the Fedora that's on it, you simply want to install an Ubuntu 11.10 on it, is that right? If so, there's a slight deviation from the standard installation flow that you need to make, detailed here