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References: <27087376D1C14132A3CC1B4016912F6D@multiplay.co.uk>
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Date: Wed, 31 Oct 2012 13:48:19 -0700
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Subject: Re: ZFS corruption due to lack of space?
From: Artem Belevich <art@freebsd.org>
To: Steven Hartland <killing@multiplay.co.uk>
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On Wed, Oct 31, 2012 at 10:55 AM, Steven Hartland
<killing@multiplay.co.uk> wrote:
> At that point with the test seemingly successful I went
> to delete test files which resulted in:-
> rm random*
> rm: random1: Unknown error: 122

ZFS is a logging filesystem. Even removing a file apparently requires
some space to write a new record saying that the file is not
referenced any more.

One way out of this jam is to try truncating some large file in place.
Make sure that file is not part of any snapshot.
Something like this may do the trick:
#dd if=/dev/null of=existing_large_file

Or, perhaps even something as simple as 'echo -n > large_file' may work.

Good luck,
--Artem