# 11.2 mirror broken boot revisited



## Paul Floyd (Oct 26, 2019)

Hi

My freebsd system has been dead since I attempted to upgrade to 11.2 quite some time ago. 

I tried following these instructions









						Upgrade 11.2 ZFS: i/o error - all block copies unavailable
					

During an upgrade from 11.1 to 11.2, upon first reboot, I get the following error:  ZFS: i/o error - all block copies unavailable  /boot/kernel/kernel text=0x1547d28 ZFS: i/o error - all block copies unavailable  elf64_loadimage: read failed can't  load 'kernel'   I have tried the following...




					forums.freebsd.org
				




All seemed to go OK apart from the gpart create command, which failed with a 'file exists' error.

Is gpart destroy -F the answer here?


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## Paul Floyd (Oct 26, 2019)

I tried gpart destroy, and all the steps in the previous link looked OK.

On rebbooting I still just get screenfulls of hex read error messages and eventually the OK loader prompt
Any suggestions other than either reinstall or abandon freebsd?


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## k.jacker (Oct 26, 2019)

Please note that careless use of `gpart destroy -F …` is probably the best preparation to start over  


Paul Floyd said:


> Any suggestions...


I'd start by booting a FreeBSD installer and run `gpart show` and `zpool import` to see if there's anything left.


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## Paul Floyd (Oct 26, 2019)

I was quite careful.

No problems booting from dvd and running zpool import. zpool status and zpool scrub are clean.

gpart list and gpart all look resonable.

ada2 and ada3 both have

1 freebsd-boot 512k
   - free - 492k
2 freebsd-swap 2G
3 freebsd-zfs 3.6T
   - free - 836k

after dropping down to the OK loader prompt, lsdev does show 

read 1 from 7814037167 to 0xdafc44e0, error: 0x1

7814037167 would be the last sector on the disk, or thereabouts. No idea what the hex value means or the error code.


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