maverick1987 Author

Level 1

34 points

Slow boot time after update to Mojave - External SSD

Hello!

I have a iMac 21" 4k 3,1ghz 2015. I installed an external SSD Samsung 860 Evo 512gb to avoid losing the Apple 1yr warranty if I opened my iMac by myself.

So when I was using APFS format and OSX High Sierra, my iMac used to start, then 2 seconds with a completely empty screen(black) looking for the boot SSD, then the Apple logo appear and it would take another 18 seconds for the system to start completely.

Total boot time = ~20secs.

Now I installed the new MacOS Mojave and my current boot time are very very slow; when I turn on the computer the screen stills black for 2 minutes more or less "looking for my external boot SSD" and then the Apple logo appear and +18secs the system starts.

My current boot time = More than 2~3minutes!!!!

I have also a MacBook Pro 2017 TouchBar and TouchID with 512GB integrated SSD also with APFS format, and update this from High Sierra to Mojave at the same day/time to the iMac. Fortunately the MacBook Pro booting done in about 20secs.

So... There is any solution for fixing this "everlasting" blank screen when booting the iMac with MacOS Mojave and external SSD with APFS format?

I've researched about this, but I can't find anything to solve it. So, I hope someone here may help me!

Thanks!

iMac, macOS Mojave (10.14)

Posted on Sep 28, 2018 8:34 AM

Top-ranking reply

JB Cheong

Level 1

4 points

Posted on Jan 22, 2019 6:25 PM

Having read positive reviews on 10.14.3 solving this issue, I went ahead to download its COMBO update, and to my horror, it refused to install and update my external USB 3 Drive. The SSD drive is simply not selectable.

So I decided to try to update to 10.14.3 directly via Software Update instead, and it works!!

My iMac finally boots up swiftly like it used to.

I subsequently apply the 10.14.3 COMBO Update through the system, and this time it went through without any problem.

I'm glad the issue is resolved, for me at least.

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345 replies

RPAEA

Level 1

79 points

Dec 12, 2018 5:07 PM in response to TravellingKiwi

Let us know. I can’t do this till my day off as my iMac is also my Home Sharing machine.

grdh20

Level 1

84 points

Dec 14, 2018 7:02 AM in response to TravellingKiwi

Unfortuatley the time it would take me to do the above erase and re-do of multiple drives isn't an option anytime soon if ever. Apple needs to do better.

RPAEA

Level 1

79 points

Dec 14, 2018 9:12 AM in response to TravellingKiwi

Oh I did find something interesting. Using Disk Utilities when I hit the "i" icon, none of my drives, even the boot drive shows as bootable startup disk. It says "no". Weird.

grdh20

Level 1

84 points

Dec 17, 2018 9:02 AM in response to Jaap de Groote

Reversing APFS back to HFS is not the solution. The solution is for Apple to figure out the problem and fix it!

grdh20

Level 1

84 points

Dec 19, 2018 7:21 AM in response to RPAEA

The Sleep crahses are most likley related to a bridge os (T2 chip) crsah that happens on many recent macbooks and imac pro etc. macs with T2 chips. A whole other problem.

VericatC

Level 1

4 points

Dec 21, 2018 12:51 AM in response to BorisKnowsBest

Sounds Good!!

Omar100

Level 1

4 points

Dec 21, 2018 3:59 AM in response to BorisKnowsBest

oh that sounds great, hopefully...

Dec 21, 2018 10:18 AM in response to gerofromronnenberg

Yes, the bug is fixed only in the BETA 2, I updated this morning after having the boot delay for couple of weeks.

cheers

Boris

Dec 23, 2018 3:31 AM in response to JDW1

That seems to be a totally different problem, you should maybe open a new thread about your "two chimes" issue! This thread is for the USB boot delay problem only.

Best

grdh20

Level 1

84 points

Dec 24, 2018 6:03 AM in response to maverick1987

latest beta does seem to improve boot time with TB3 drives connected.

Dec 24, 2018 9:16 AM in response to grdh20

Thunderbolt drives and enclosures haven’t had these problems anyway, the boot delays described in this thread are USB-related only.

grdh20

Level 1

84 points

Dec 24, 2018 11:56 AM in response to gerofromronnenberg

Oh they have had them too trust me.

Dec 24, 2018 5:09 PM in response to JDW1

Let's all wait until 10.14.3 is released to the public. As two guys before said, our problems should be gone by then!

PF2UK

Level 1

4 points

Jan 18, 2019 6:37 AM in response to gerofromronnenberg

Does anyone know if this is still working with beta 4 of 10.14.3?

PF2UK

Level 1

4 points

Jan 18, 2019 7:27 AM in response to BorisKnowsBest

Thanks for sharing that with us. Hope they release the final version soon!

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Slow boot time after update to Mojave - External SSD