MP 1,1-5,1 Mac Pro mysteriously starting up from Carbon Copy Cloner backup

[DustyShaw]

1 out of 2 times the mac pro is starting up from a CCC backup. That backup is not selected as the startup disc. The startup disc selected is "Mac Pro". The backup disc "MacProBU2" is not selected as the startup disc. I have checked CCC literature but find nothing about this.

My workaround is simply to restart and then it starts up from "Mac Pro" as it should, but this takes time so I'd like to find out why this is happening and how to fix it.

Anyone ever have this issue or know how to fix it?

MacPro 2008
El Capitan
CCC 5.1.5

PS Please do not tell me to update CCC or OS. I do not update the OS or apps on this machine. I have been using the same configuration for months with no problem until a few weeks ago.

 

[Weaselboy]

When that happens and it boots to the CCC disk, can you see the other Mac Pro drive in Disk Util or elsewhere?

I'm wondering if you have the beginnings of a drive failure, and the system does not see the Mac Pro drive, so chooses an alternative.

 

[MarkC426]

Ideally your clone should be separate from your Mac.
If your Mac was stolen/caught fire....whatever, your backup is gone also.

 

[KeesMacPro]

I've had something similar a couple of years ago when I had a MP 3,1.
The OS was installed on a SSD with a PCIe adapter (Accelsior S) which appeared to cause issues .
So at startup it would randomly boot from the first bootable drive in the HDD bays.

 

[DustyShaw]

When that happens and it boots to the CCC disk, can you see the other Mac Pro drive in Disk Util or elsewhere?

I'm wondering if you have the beginnings of a drive failure, and the system does not see the Mac Pro drive, so chooses an alternative.

Thanks I will check that next time it happens. The main drive is only a few months old though, I hope it's not that.

 

[DustyShaw]

Ideally your clone should be separate from your Mac.
If your Mac was stolen/caught fire....whatever, your backup is gone also.

It is, thanks.