[dm-devel] multipath-tools 0.7.4 failure to remove device

[Martin Wilck]

On Mon, 2018-01-15 at 16:44 +0100, Julian Andres Klode wrote:
> 
> It was your commit that made it imply -n that caused the test failure
> :)
> I understand your position on that, but reverted it for Ubuntu,
> because,
> while it might be somewhat broken, it's at least the same level of
> broken
> as before.

I'd like to understand that better. Why would this break boot?

If the root device was already in the "wwids" file, it wouldn't be
"new", and thus "-n" should have no effect. 

If the root device is a "real" multipath device with >=2 paths, there's
of course a difference with and without "-n". But in that case, I'd
expect the device to be listed in "wwids", because it should have been
detected as multipath device during installation already.

Finally, if the root device is not a real multipath device (1 path
only), and is not in "wwids", my patch would cause it not to be
multipathed, which is the Right Thing todo AFAICS.

The same reasoning applies to other devices required for booting
besides the root FS (swap or whatever).

What am I missing here?

Martin

-- 
Dr. Martin Wilck <mwilck at suse.com>, Tel. +49 (0)911 74053 2107
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