OS Mojave will not boot from external SSD anymore

[mariuste]

Hello

First some background: I have a Macbook pro retina late 2013 (osx Mavericks on the internal drive). I recently installed Mojave on an external SSD, connected over usb3 to my laptop. So only way to boot Mojave is to invoke the startup manager and choose it as the startup disk from there, because mavericks does not recognize it due to being apfs. I was told this should be workable. And so it was for a week or so and Mojave was running smoothly off the external drive.
Now, when I select Mojave as the boot drive in the startup manager I do not get past the apple logo and is stuck on loading. The first time I suspected it was just slow and waited over night. The next day nothing had changed, even no progress it seemed, either.

I come to think of two things that did change in my setup and that may or may not be the reason for this.

1. I have disconnected the Mojave drive a couple of times from the USB3 port, without ejecting it. Because mavericks doesn't recognize it, only option to my knowledge is to eject from disk utility, which I did not.
2. I have changed the USB3 cable to a shorter one, and the issue started after this so I first thought it was the cable. I have tried different cables since then and also on the other USB3 port on my MBP, issue still persist.

However, what I know want to know, is there any other option now than to erase the drive and do the installation again? What is the most likely reason for this issue?

Marius

 

[MarkC426]

Why not upgrade Mavericks to Mojave on the internal drive...?

 

[DeltaMac]

All you need is an external Mojave installer. Boot to that, then reinstall, with the external drive as the destination for the install. Reinstalling should fix the boot issue on the external.
I understand your situation - and that Mavericks doesn't see the drive at all.
Try to avoid just unplugging that external drive - If you restart to boot to your normal Mavericks system, try to remember to unplug that drive -- A good time would be to listen for the boot chime. Any external drive can be safely un-plugged during that chime, or within a few seconds after you hear the chime.
Maybe it would be a good idea to make it a habit to shut down completely, when you want to boot back to Mavericks. Then you will be able to connect or disconnect anything you like...

(I agree with MarkC246 - the oldest Mac system that will see the Mojave drive directly is Sierra - do you need to stay with Mavericks?)

 

[mariuste]

Thank you for replying, and sorry for my late reply. I am still on mavericks because I have apps that I use and (unfinished) projects (Music production) that will not be available on newer OS. I am in the process of migrating over though. Thank you for the suggestion DeltaMac, I will follow it.