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Subject: Re: zpool import -N mounts filesystems anyway
To: David Christensen <dpchrist@holgerdanske.com>,
 freebsd-questions@freebsd.org
References: <7f41df25-df2e-298e-d33e-cc95874e831c@bluerosetech.com>
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From: Mel Pilgrim <list_freebsd@bluerosetech.com>
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Date: Sun, 18 Jun 2017 20:17:44 -0700
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On 06/18/2017 13:19, David Christensen wrote:
> 
> Have you tried setting canmount to noauto?

It also doesn't work as expected.

# zfs get -r canmount,mountpoint backupA
NAME        PROPERTY    VALUE                   SOURCE
backupA     canmount    noauto                  local
backupA     mountpoint  /backup-ext/backupA     local
backupA/z0  canmount    noauto                  local
backupA/z0  mountpoint  /backup-ext/backupA/z0  inherited from backupA

# zpool export backupA
# zpool import backupA
# zfs list -ro name,mounted,mountpoint backupA
NAME        MOUNTED  MOUNTPOINT
backupA         yes  /backup-ext/backupA
backupA/z0       no  /backup-ext/backupA/z0


Despite canmount=noauto, ZFS mounted the root dataset automatically 
anyway.  The only way I know of to guarantee a dataset won't be mounted 
on import, despite documentation to the contrary, is to make sure it has 
or inherits mountpoint=none.