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Subject: Re: zfs problems after rebuilding system [SOLVED]
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From: Pete French <petefrench@ingresso.co.uk>
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Date: Sat, 3 Mar 2018 16:19:09 +0000
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> That won't work for the boot drive.
> 
> When no boot drive is detected early enough, the kernel goes to the
> mountroot prompt.  That seems to hold a Giant lock which inhibits
> further progress being made.  Sometimes progress can be made by trying
> to mount unmountable partitions on other drives, but this usually goes
> too fast, especially if the USB drive often times out.



We have this problem in Azure with a ZFS root, was fixed by the pacth in 
this bug report, which actually starts off being about USB.

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=208882

You can then set the mountroot timeout as normal and it works.

I wold really like this patch to be applied, but it seems to have 
languished since last summer. We use this as standard on all our cloud 
machines now, and it works very nicely.

-pete.