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Is Sierra Installer okay?

Texas_Toast

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In the past, I downloaded the macOS Sierra installer onto my old MacBook. And a couple of months after this, I ran CCC and it said that files related to this installer were corrupt.

So I deleted this file from my old MacBook.

Today, I was going to download a clean copy of the macOS Sierra installer onto my newer Retina. However when I did this, I got a pop-up saying it wanted to *install* Sierra.

After some searching, I discovered that I had a "Install macOS Sierra.app" (5.03 GB) filed away somewhere on my Retina.

Clearly not remember where things were at or what I had done in the past, I'm a little afraid that this second copy could be corrupt too, and I'd hate to want to re-install Sierra down the road only to find my copy is bad and that I can no longer get it off of Apple's website.

Short of downloading the 5GB file again, is there an easy way to verify if this 2nd copy on my Retina is in working order??
 
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chown33

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I'd test it by installing it to an external drive of some kind.

Mine was installed to an empty 32GB SD card, so a huge drive isn't needed.
 
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Texas_Toast

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I'd test it by installing it to an external drive of some kind.

Mine was installed to an empty 32GB SD card, so a huge drive isn't needed.

So the fact that it luanches the installer screen isn't resurrance enough, huh?

How do I install to an external drive and not wipe out my MacBook's OS?

Does the installer let you point to a particular drive?
 
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chown33

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I'm pretty sure I made a replica of my boot partition using CCC, targeting the SD card. Then I applied the OS installer to the SD card. It was some time ago, so I'm not certain, but that's likely what I did because that's the way I usually test an OS upgrade (replicate to external, then install there).

If you have a full backup of your internal drive, then even a wipeout using Internet Recovery would get things back. So do the backup before attempting anything else. You've mentioned before that you regularly maintain such backups, so I don't see why you'd mistrust your own backup procedures for recovering things.


I'm fairly sure the installer will reach some point where it asks you to commit to installing the OS upgrade. I don't recall the exact wording, but anything that happens before that point can be cancelled or stopped. You can generally tell by the presence of a "Cancel" button, or possibly one that says "Back" that goes back 1 step. One might also be able to choose "Quit" from a menu.

So I suggest that you make a complete backup first, eject and set the disk aside, then carefully step through the installer, and don't commit to anything. Take notes, and keep them with the installer for later reference.

It's possible that booting from the external might give you different installer options than being booted from the internal. So doing that might be worthwhile.

If you do commit to something accidentally, the backup you made should protect you, so the worst that happens is you spend some unwanted time doing a restore.

This pretty much outlines my approach to every OS upgrade I'm not sure of.
 
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Texas_Toast

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You've mentioned before that you regularly maintain such backups, so I don't see why you'd mistrust your own backup procedures for recovering things.

Because I'm not sure I have ever recovered my clone back onto my laptop. Guess I should try that, huh? :oops:

I guess could also create a bootable USB installer with the macOS installer I want to test, and then install Sierra on my "sitting there doing nothing" backup Retina, and if that works, then I guess the installer file is okay, right?

I also suppose that is more idiot-proof than trying to install Sierra onto an external drive from a working laptop, because the installer might install to my laptop and not the external drive.
 
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Texas_Toast

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You will avoid the chance of accidentally installing to the wrong drive, if you create a bootable installer from your download macOS installer app.

I wrote a guide on how to do that - guess I should read it, huh?

I guess I should stop being lazy and figure how to create a bootable instalelr again, and then (literally) dust off my 2nd Retina, and try to install msOS Sierra, and if it works then my "Install macOS Sierra.app" file (and instalelr) are good.

And I suppose I should also practice recovering from a CCC clone and make sure I get more comfortable with that.
 
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chown33

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Because I'm not sure I have ever recovered my clone back onto my laptop. Guess I should try that, huh? :oops:
If you've never confirmed that your backups will restore correctly, then at best you only have half a lifeboat.

You might be lucky and have a whole lifeboat, but nobody really knows.


In the olden days of mag tape and timeshare minis where I worked, the guy who was making backup tapes of a PDP-11 running Unix was supposed to be doing read-after-write to confirm the tapes were good. It turns out, he wasn't.

With many weeks of tapes in storage, there was an HD head crash. When the tapes were read to recover data, it turned out they were essentially empty, because the write-head on the tape drive had failed. Some people had been doing their own backups to other storage (8" floppies), so they recovered OK, but it took a lot of time. Others lost weeks of work, some of which had to be reconstructed from line-printer listings.
 
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Texas_Toast

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If you've never confirmed that your backups will restore correctly, then at best you only have half a lifeboat.

You might be lucky and have a whole lifeboat, but nobody really knows.

I retract my earlier statement. Sorry, it's a lazy summer Saturday and my brain is off. (Think I need to go get some pizza!) :D

Everytime I run CCC, I clone an external HDD, and afterwards I boot to it and make sure that I can log into my admin user and regular user, and depending, I will usually spot-check some critical files (e.g. financial spreadsheet, sentimental photos, etc).

So I do check my clone every time.

However, while I *think* I created a bootable installer of macOS Sierra and tried to re-install Sieraa onto my two flaky Retinas - both with bad logic boards - that were acting up last year, I don't recall to be honest?!

Likewise, I have never used a working CCC clone and restored from that. (Since I know I have multiple working *bootable* CCC clones of my Macs, I just never thought to practice installing that working clone back onto my laptop, so I guess I am guilty of not doing a full "recovery"!)


In the olden days of mag tape and timeshare minis where I worked, the guy who was making backup tapes of a PDP-11 running Unix was supposed to be doing read-after-write to confirm the tapes were good. It turns out, he wasn't.

With many weeks of tapes in storage, there was an HD head crash. When the tapes were read to recover data, it turned out they were essentially empty, because the write-head on the tape drive had failed. Some people had been doing their own backups to other storage (8" floppies), so they recovered OK, but it took a lot of time. Others lost weeks of work, some of which had to be reconstructed from line-printer listings.

OUCH!! Did he keep his job? :eek:
[doublepost=1564266489][/doublepost]
I retract my earlier statement. Sorry, it's a lazy summer Saturday and my brain is off. (Think I need to go get some pizza!) :D

Everytime I run CCC, I clone an external HDD, and afterwards I boot to it and make sure that I can log into my admin user and regular user, and depending, I will usually spot-check some critical files (e.g. financial spreadsheet, sentimental photos, etc).

So I do check my clone every time.

However, while I *think* I created a bootable installer of macOS Sierra and tried to re-install Sieraa onto my two flaky Retinas - both with bad logic boards - that were acting up last year, I don't recall to be honest?!

Likewise, I have never used a working CCC clone and restored from that. (Since I know I have multiple working *bootable* CCC clones of my Macs, I just never thought to practice installing that working clone back onto my laptop, so I guess I am guilty of not doing a full "recovery"!)




OUCH!! Did he keep his job? :eek:

Over the next day or so, I will be good and try to make a bootable macOS Sierra USB installer and then try and install Sierra onto my - missing an OS - 2nd Retina laptop.

I will also try and restore a CCC clone from Retina #1 and install it onto empty Retina #2 and make sure I know how to do that.

Then I guess I will be in better shape, huh?
 
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Fishrrman

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Feb 20, 2009
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If you can download the original installer DIRECTLY from Apple, do that.
This will ensure that you get the latest version.

The installer app will download and go into your applications folder.
Then you will be presented with the "install" opening screen (as if you were going to do a re-install).
NO PROBLEM.
Just go to the file menu and choose "quit".
The installer will quit.

Now... move it somewhere else for safekeeping.
 
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Texas_Toast

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If you can download the original installer DIRECTLY from Apple, do that.
This will ensure that you get the latest version.

The installer app will download and go into your applications folder.
Then you will be presented with the "install" opening screen (as if you were going to do a re-install).
NO PROBLEM.
Just go to the file menu and choose "quit".
The installer will quit.

Now... move it somewhere else for safekeeping.

How often does Apple "version" its OS installer?

Since this is Sierra, it is sorta hard to imagine the installer that I have is much if any different than the installer I could re download.
 
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Texas_Toast

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So yesterday I read the guide that I made for myself on how to create a USB installer. (Glad I took notes!)

I dug out a new USB drive, and used the "macOS Sierra Installer.app" file that I had filed away and was able to successfully create the installer.

But now I have a new issue...

I took my newly created Sierra installer, and I plugged it into my Retina #2 laptop which had a messed up Sierra OS on it.

The install was going well, but at one point it said it needed like 30 minutes to install files or whatever.

Because of the long wait time, I decided to go for a walk, and when I returned from my walk, I was surprised by what I saw...

On my Retina #2, there was a normal Sierra login screen asking for a username and password, PLUS there was a custom message that I usually create installing a new OS. (i.e. It had to be the old OS I was seeing?!)

I was expecting my USB Sierra installer to completely wipe my hard-drive and install a clean copy of Sierra, so why did that not happen?? :confused::confused:

Obviously I cannot comment on what screens may have come up after I left, but I was expecting when I came back to see some installer screen asking me to create a username and password...

What happened?
 
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Mr_Brightside_@

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So yesterday I read the guide that I made for myself on how to create a USB installer. (Glad I took notes!)

I dug out a new USB drive, and used the "macOS Sierra Installer.app" file that I had filed away and was able to successfully create the installer.

But now I have a new issue...

I took my newly created Sierra installer, and I plugged it into my Retina #2 laptop which had a messed up Sierra OS on it.

The install was going well, but at one point it said it needed like 30 minutes to install files or whatever.

Because of the long wait time, I decided to go for a walk, and when I returned from my walk, I was surprised by what I saw...

On my Retina #2, there was a normal Sierra login screen asking for a username and password, PLUS there was a custom message that I usually create installing a new OS. (i.e. It had to be the old OS I was seeing?!)

I was expecting my USB Sierra installer to completely wipe my hard-drive and install a clean copy of Sierra, so why did that not happen?? :confused::confused:

Obviously I cannot comment on what screens may have come up after I left, but I was expecting when I came back to see some installer screen asking me to create a username and password...

What happened?
Did you explicitly wipe the SSD in Disk Utility prior to running the installer?
 
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Texas_Toast

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Did you explicitly wipe the SSD in Disk Utility prior to running the installer?

No.

I didn't know I had to...

In the old days, if I installed an OS CD/DVD and re-installed OS-X (or Windows), then you got a brand new computer, no questions asked. (I suppose some of your old data may have stille xisted on the hard-drive and could have been recovered using forensic tools, but you had a brand new OS.)

So what happened when I staretd installing macOS Sierra from my bootable USB installer and then I went for a walk?! o_O
 
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Mr_Brightside_@

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macOS Sierra was reinstalled on your Mac. This is expected behaviour and exactly what you said happened should have happened.

I don't know that Apple makes restore images of macOS available for public use. I would vastly prefer an installer that forces me to manually wipe the drive to one that does it automatically.

If you want a fresh install and your data is backed up, plug the USB back in,
wipe the SSD first via Disk Utility,
and then install Sierra.
 
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Texas_Toast

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macOS Sierra was reinstalled on your Mac. This is expected behaviour and exactly what you said happened should have happened.

I don't know that Apple makes restore images of macOS available for public use. I would vastly prefer an installer that forces me to manually wipe the drive to one that does it automatically.

If you want a fresh install and your data is backed up, plug the USB back in,
wipe the SSD first via Disk Utility,
and then install Sierra.

@Mr_Brightside_@,

I'm a bit confused by all of this... (Also embarassed that I created an installer and never tried it out!)

Topic #1:
You seem to be saying that when you install/re-install a version of macOS using a bootable installer, that your data goes untouched? Is that true?

And is that true if you went from say Sierra to Mojave?


Topic #2:
If I truly installed a fresh copy of Sierra onto my second Retina, then how could it have the same user accounts and login message already set up?

That seems pretty dangerous if you install an OS and all of the old accounts still linger...


Topic #3:
Am I understanding you that if I option-boot to my bootable USB installer, and then I choose Disk Utility from the pre-boot popup window, that I could re-format my second Retina's intenal hard-drive, and then afetr that if I use the installer to install Sierra that I would get a truly "clean" install of the OS?

Presumably that would also allow me to create new user accounts from scratch, right?
 
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Mr_Brightside_@

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@Mr_Brightside_@,

I'm a bit confused by all of this... (Also embarassed that I created an installer and never tried it out!)

Topic #1:
You seem to be saying that when you install/re-install a version of macOS using a bootable installer, that your data goes untouched? Is that true?

And is that true if you went from say Sierra to Mojave?


Topic #2:
If I truly installed a fresh copy of Sierra onto my second Retina, then how could it have the same user accounts and login message already set up?

That seems pretty dangerous if you install an OS and all of the old accounts still linger...


Topic #3:
Am I understanding you that if I option-boot to my bootable USB installer, and then I choose Disk Utility from the pre-boot popup window, that I could re-format my second Retina's intenal hard-drive, and then afetr that if I use the installer to install Sierra that I would get a truly "clean" install of the OS?

Presumably that would also allow me to create new user accounts from scratch, right?
1. yes, yes
2. you didn't install a fresh copy. you reinstalled, because you didn't wipe the SSD.
3. this is correct
 
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DeltaMac

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If you boot to your bootable installer, and simply run "Reinstall macOS", choosing your boot drive as the destination, then your system is reinstalled. Your files, settings, and apps that you may have on that drive are not touched. The reinstall just reinstalls your system files. The boot drive is NOT erased first, unless you choose to do that in Disk Utility. The install process does not give you an option to erase the drive during the install. That option has not been in the OS X or macOS install since OS X 10.5 (Leopard)
#2 - the reinstall does not touch your accounts, or your login window (again, unless you choose to erase the drive first)
#3 - You are correct. If you boot to your bootable USB installer, then erase the drive with Disk Utility, that will then give you a truly "clean" install of the OS. (What I would call a "Nuke 'n Pave" :cool: ), ready to reinstall apps, and add whatever other documents, etc, that you need.
 
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Texas_Toast

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If you boot to your bootable installer, and simply run "Reinstall macOS", choosing your boot drive as the destination, then your system is reinstalled. Your files, settings, and apps that you may have on that drive are not touched. The reinstall just reinstalls your system files. The boot drive is NOT erased first, unless you choose to do that in Disk Utility. The install process does not give you an option to erase the drive during the install. That option has not been in the OS X or macOS install since OS X 10.5 (Leopard)
#2 - the reinstall does not touch your accounts, or your login window (again, unless you choose to erase the drive first)
#3 - You are correct. If you boot to your bootable USB installer, then erase the drive with Disk Utility, that will then give you a truly "clean" install of the OS. (What I would call a "Nuke 'n Pave" :cool: ), ready to reinstall apps, and add whatever other documents, etc, that you need.

Why does Apple do it that way?

I am of the mindset that when you want to install/re-install an OS it is either because you want a different version or because your computer is fubared and you need to start over.

By just re-installing OS related files, doesn't that usually still leave you with a screwed up computer if you were having issues?

(Curious as to what % of the time it is system files casuing issues and what % of the time it is user/preference files??) o_O

This is very interesting, and as usual, I am learning a bunch thank to y'all!! :apple:

Let me go back and try this again - practice makes perfect!
 
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Mr_Brightside_@

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Why does Apple do it that way?

I am of the mindset that when you want to install/re-install an OS it is either because you want a different version or because your computer is fubared and you need to start over.

By just re-installing OS related files, doesn't that usually still leave you with a screwed up computer if you were having issues?

(Curious as to what % of the time it is system files casuing issues and what % of the time it is user/preference files??) o_O

This is very interesting, and as usual, I am learning a bunch thank to y'all!! :apple:

Let me go back and try this again - practice makes perfect!
Because the vast majority of users do not back up, and so a restore image would be unwelcome.
A reinstall without wiping files can often be beneficial.
 
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DeltaMac

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The reinstall also does some "pruning" of system caches, and other temp files. The reinstall can often be a good fix for weird little annoyances that might show up occasionally.
 
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Texas_Toast

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P.S.

a.) When I format my internal HDD, do I just format it as one partition, and assume the installer knows how to create the "boot partition" on its own, or do I need to worry about that myself?

b.) Do I have to decrypt my HDD before I can wipe it clean and do a fresh install of Sierra?
 
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DeltaMac

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Actually, leaving it encrypted is a good way to securely erase your drive:
Boot to the installer.
Disk Utility: Show all Devices (click the View icon, and choose Show All Devices)
Select the line with the drive info (not the volume name line).
Click the Erase tab, name the volume if you like, and continue by clicking on the Erase button.
(An encrypted volume would also be erased, and would be secure enough to be acceptable for most high security needs)

The macOS install will take care of making the system partition bootable, assuming the drive is working OK. There's not really anything you need to do.
 
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Texas_Toast

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If you've never confirmed that your backups will restore correctly, then at best you only have half a lifeboat.

You might be lucky and have a whole lifeboat, but nobody really knows.

Okay, I took time today to teach myself how to restore a CCC clone onto my test Retina (#2).

Now not only do I know how to bot to my clones, but how to restore them should my laptop ever become corrupted or a HDD fails.

Good to know!

I also played around and was able to successfuly wipe my HDD clean and re-isntall Sierra from my bootable installer.

Also good to know!

I think I am now safe in these two areas.

Thanks to everyone in this thread for the help!! :apple::apple::apple:
 
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