# No MBR Installed After Boot



## joshdmiller (Aug 11, 2011)

I have tried the installation from the 8.2 amd64 ISO three times and each time it fails to install the boot loader to the MBR. I receive GRUB error 17 when I try to boot post-install. The installation is fairly uneventful and gives no errors. I tried twice with BootMgr and once with the Standard boot loader.

After the first, I attempted to manually install to the mbr with boot0cfg off a live disk per a few other threads, but with no success (though it reported no error when installing to ada0).

My computer is a Phenom II on an nvidia-based board with two sata drives; the primary, first-channel hard drive always has the operating system and the second-channel hard drive is for data storage.

I have many years experience with Linux, but I am new to the BSDs and this has me a little stumped.

What am I doing incorrectly?


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## graudeejs (Aug 11, 2011)

http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/install.html
http://www.daemonforums.org/showthread.php?t=1538 (Good read)


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## joshdmiller (Aug 11, 2011)

killasmurf86 said:
			
		

> http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/install.html
> http://www.daemonforums.org/showthread.php?t=1538 (Good read)



I, of course, have already read the handbook. I also followed along all three times with the instructions in the installation section. As I said, sysinstall asks the questions with regard to the boot loader, it just does not get installed to the MBR.

Thanks for the second link; I read the instructions and they make sense, but I am also missing where in those instructions corey_james installed the bootloader instructions to the MBR. Was that handled by one of the install scripts executed?


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## graudeejs (Aug 11, 2011)

You said, you have 2 HDD's, perhaps take out one of them... and see what happens.
Also without you telling exact commands you entered we really can only guess, when went wrong.

You know, it works pretty dam well for rest of us (no offense)

BTW, personally I prefer to use GPT, but some other OSes doesn't support it (however I only run FreeBSD)
I think getting GPT to work, is much easier, than MBR


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## joshdmiller (Aug 11, 2011)

I understand that it works well for others which is why the question I asked wasn't "what's wrong with the installer" but "what am I doing incorrectly". I have been in software long enough to know that when something goes wrong the problem is typically the user's fault - I am just asking for help from those in the community with more experience with FreeBSD. I am not sure how you got the impression I was saying otherwise, but I apologize for the confusion nonetheless.

In terms of the MBR/GPT confusion, I can only say that on the primary disk GRUB was installed previously with instructions to the MBR from Arch Linux, that the GRUB instructions are still there, and that my computer attempts to follow those instructions, which obviously fail. There are no other operating systems on this computer, so whatever FreeBSD wants to do, it can. I made no attempt at customization as this is my first FreeBSD installation.

I just used the CD as I said in my previous post and Sysinstall did whatever it does by following the instructions in the manual - only after it did not work did I attempt to run additional commands to fill in the deficit. My analogy was GRUB. If it's not there, boot into a live disk and run the GRUB installer. Searching the forums led me to these commands, which seem to have had no effect: 


```
# ls /dev/ad*
/dev/ad4
/dev/ad4s1
/dev/ad4s1a
/dev/ad4s1b
/dev/ad4s1d
/dev/ad4s1e
/dev/ad4s1f
/dev/ad6
/dev/ad6s1
/dev/ada0
/dev/ada0s1
/dev/ada0s1a
/dev/ada0s1b
/dev/ada0s1d
/dev/ada0s1e
/dev/ada0s1f
/dev/ada1
/dev/ada1s1

# boot0cfg -B ad4
```


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## graudeejs (Aug 11, 2011)

try this
`# dd if=/boot/mbr of=/dev/da4 bs=512 count=1`
bs and count aren't really needed, but just in case... 

This should overwrite boot sector brutally.


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## joshdmiller (Aug 11, 2011)

*Solved*



			
				killasmurf86 said:
			
		

> try this
> `# dd if=/boot/mbr of=/dev/da4 bs=512 count=1`
> bs and count aren't really needed, but just in case...
> 
> This should overwrite boot sector brutally.



Thanks for the quick reply. I tried this (assuming you meant ad4 and not da4) and it copied the data, but on reboot it just changes the GRUB error from 17 to 22 (missing partition).

But, per your earlier suggestion, I removed the storage drive on sata 2, reinstalled, and everything worked ok. Since I obviously need that drive, I shutdown the system, added the hard drive back, and boot was still successful.

Thank you very much for your help. My problem is solved. But I am curious - can you venture a guess as to what the problem was?


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## wblock@ (Aug 11, 2011)

killasmurf86 said:
			
		

> try this
> `# dd if=/boot/mbr of=/dev/da4 bs=512 count=1`
> bs and count aren't really needed, but just in case...
> 
> This should overwrite boot sector brutally.



It will also overwrite the partition table...

Disk Setup On FreeBSD shows MBR and GPT disk setup.


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## graudeejs (Aug 12, 2011)

joshdmiller said:
			
		

> Thanks for the quick reply. I tried this (assuming you meant ad4 and not da4) and it copied the data, but on reboot it just changes the GRUB error from 17 to 22 (missing partition).
> 
> But, per your earlier suggestion, I removed the storage drive on sata 2, reinstalled, and everything worked ok. Since I obviously need that drive, I shutdown the system, added the hard drive back, and boot was still successful.
> 
> Thank you very much for your help. My problem is solved. But I am curious - can you venture a guess as to what the problem was?



Grub is a such a ^*+&. I really hate it. It does all kinds of dirty hacks...
I dunno how, but most of all I hate when it somehow magically can make your PC skip booting from CD

as to your exact problem... I dunno



			
				wblock said:
			
		

> It will also overwrite the partition table...
> 
> Disk Setup On FreeBSD shows MBR and GPT disk setup.



Ups... your right. I need to write that down to my permanent memory storage. I haven't used MBR for about 3 years


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