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Author Topic: What does this mean?  (Read 1783 times)

Offline jwboyd

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What does this mean?
« on: December 04, 2016, 04:19:19 PM »
I wanted to start up from a Carbon-Copy-cloned external drive.

It did not start up, but a circle with an arrow-pointed lightning bolt through it jerked its way diagonally across the screen.

I powered down, then powered up again. I am running on that external drive now and can detect no problems.

My guess is that this external drive may be beginning to fail.

Your thoughts?

Thanks!
Joe
« Last Edit: December 04, 2016, 04:19:47 PM by jwboyd »
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Offline jchuzi

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What does this mean?
« Reply #1 on: December 04, 2016, 06:07:36 PM »
I would suggest running the Apple Hardware Test but I don't know if you can run it on an external drive. If that's not the case, do you have Drive Genius, TechTool Pro or TechTool ProToGo? They can do a variety of tests. If none of these are available, run SMART with Disk Utility. It's not the last word but you may find something.

EDIT: I forgot about this: If you have set CCC to clone the Recovery Partition, you can boot from the RP on the external drive and run the AHT.
« Last Edit: December 04, 2016, 06:12:16 PM by jchuzi »
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Jon

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Offline Xairbusdriver

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What does this mean?
« Reply #2 on: December 04, 2016, 06:57:39 PM »
Sounds like you got a "Target Disk" mode icon! Would you believe I can't find an image of that emblem/icon?! wallbash.gif Did you happen to have the "T" key held down when you tried the startup? dntknw.gif Maybe there's something in the CCC Help text...
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Offline kimmer

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What does this mean?
« Reply #3 on: December 04, 2016, 07:18:24 PM »
I'm wondering if you are using a Thunderbolt cable? Look at the image on this page for information on using Target Disk mode:

https://answers.syr.edu/display/os/Target+D...c+Data+Transfer
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Offline jwboyd

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What does this mean?
« Reply #4 on: December 04, 2016, 08:12:35 PM »
Yes, Kimmer, it was the Thunderbolt icon!

No idea why, as I have no Thunderbolt cables connected. All my externals are on USB.

The mystery deepens. . .

Joe
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Offline jchuzi

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What does this mean?
« Reply #5 on: December 05, 2016, 06:02:13 AM »
Jim is probably right about why it happened, namely that you pressed T during startup.
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Jon

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Offline jwboyd

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What does this mean?
« Reply #6 on: December 05, 2016, 09:15:04 AM »
Mystery solved!

I was able to replicate the condition by pressing T on startup.

Thanks to Kimmer, Jim, and Jon for enlightening me.

While I was at it, I ran TechTool Pro and DiskFirstAid on that drive and corrected a couple of things. Now all is well.

Joe
« Last Edit: December 05, 2016, 09:16:14 AM by jwboyd »
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