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Date: Wed, 2 Jul 2003 20:15:37 -0700
From: "David O'Brien" <obrien@freebsd.org>
To: Ian Dowse <iedowse@maths.tcd.ie>
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cc: freebsd-arch@freebsd.org
Subject: Re: Unmounting by filesystem ID
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On Sat, Jun 28, 2003 at 10:54:04PM +0100, Ian Dowse wrote:
> The patch below adds a new mount flag MNT_BYFSID that can be used
> to unmount a filesystem by specifying its filesystem ID instead of
> a path. The umount utility is changed to use this mechanism by
> default. This approach has a number of advantages:
> 
> - It avoids any lookup operations that could potentially block
>   forever, so filesystems such as NFS can be reliably unmounted
>   even if the server is not responding but looking up the root node
>   would require an RPC (maybe to an underlying filesystem).

VERY nice.