My question is twofold. First how to fix this problem, but second and more importantly how to prevent this problem from occuring again.

Using Clonezilla I created an image of Hard drive A on Computer A.
I booted up Computer B and Hard Drive B into clonezilla and restored the image!

Hard drive A and Hard Drive B will boot up perfectly in Computer A. Neither hard drive will boot up in Computer B! I can see when I boot up on Computer B that uefi is not showing as a boot option and I presume that this is the problem.

I am using Slackware Current, Elilo, GPT and identical computers in every respect.

In the past when I have done this I was creating an image of Slackware 14.2 (not current), restored image and then I always had to boot up on slackware setup and run eliloconfig again to do whatever eliloconfig does and then the hard drive would boot up on the second computer.

I can't do that this time because I am using Slackware Current as the image and I have Slackware 14.2 (original) as the Slackware Setup and I get an error message libefivar.so.1 is missing when trying to run eliloconfig.

If I download Slackware Current ISO and run setup with that, will I be able to run eliloconfig then. I am assuming that the reason it is failing is because I am running Current, but the setup install is running original 14.2 and presumably an older version of elilo and the current is running the latest kernel whereas the original is obviously running an older kernel.

Which brings me to my second question. How do I clone a hard drive for another computer without having to run setup every time to run eliloconfig for the second computer. I don't think that I am doing this correctly. Or is the normal procedure to run setup and run eliloconfig?

Actually a third question - do I need to covert a hard drive from MBR to GPT before restoring image or will this happen when I restore from an image as I may have one or two computers to do that might be running MBR?

Thank you.

None of my computers are new enough to have UEFI. However, I have been reading about it because I expect to need to know in the future.

I have read that some computers there was a 'switch' in the BIOS configuration, to use either UEFI or the old method. Does your second computer have such an option in the BIOS? If so, is it set for UEFI?

Also, from what I have read, for the UEFI there is a table stored in NVRAM on the motherboard, and I gather that when one runs 'elilo' it stores what is needed in this NVRAM --- and without the proper information in the NVRAM the UEFI software does not know what to do with the partitions on the hard-drive.

So, I think you will have to boot the second computer somehow, and run 'elilo'...

Is there some reason not to make a bootable USB flash-drive, using "usbboot.img" from
"https://mirror.slackbuilds.org/slackware/slackware64-current/usb-and-pxe-installers/", and then boot your computer with it, pass to the kernel the appropriate partition on your hard-drive, login to your system on the hard-drive, and run 'eliloconfig' and so on?

The Install disk should boot any bootable partition from the very first screen. Then you can run elilo and fix this. It's fast and easy.

This is what I tried to do, but eliloconfig won't work - presumably because I am running current and the Install disk is running 14.2. I will try downloading the latest install disk from current.

Yes both computers are set to boot UEFI. I believe that the issue is as you stated. I need to write to that table NVRAM on the motherboard which is what eliloconfig does.

If I cannot download a current install and run eliloconfig from that, I will try your suggestion of creating a usb boot disk from slackware current and running eliloconfig that way.

Thanks

If you haven't found it already, have a look below:

http://bear.alienbase.nl/mirrors/sla...4-current-iso/

You are a star! When I went to slackware.com, I could not find a current ISO (only 14.2), so you saved me a lot of time hunting around to find a current iso.

I am pleased to report that downloading the latest current and booting into setup on this allowed me to run eliloconfig and everything now works beautifully.

So I have answered question 1 - how to fix the problem and now that I understand that I am needing to update the nvram area of each motherboard I understand that I need to run eliloconfig after restoring an image, so it is not the fault of clonezilla, as each machine has a different motherboard and thus I need to run eliloconfig on each machine.

Thank you to all for your help. I understand the process better and I fixed the problem. Now if I can just find out why I am not receiving email notifications from linux questions (as I was until last week), then all wil be well with the world!