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From: "Patrick M. Hausen" <hausen@punkt.de>
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Subject: ZFS feature flags 9.2 -> 8.4?
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Date: Mon, 2 Jun 2014 10:08:17 +0200
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Hi, all,

can a zpool with these feature flags from RELENG_9_2 be accessed
and booted (!) by a RELENG_8_4 system?

FEAT DESCRIPTION
-------------------------------------------------------------
async_destroy                         (read-only compatible)
     Destroy filesystems asynchronously.
empty_bpobj                           (read-only compatible)
     Snapshots use less space.
lz4_compress                        =20
     LZ4 compression algorithm support.

There is a chance I need to downgrade a production system.
Not quite sure yet, but I wanted to check the possibilities ...

Thanks a lot,
Patrick
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