[dm-devel] [PATCH 3/3] libmultipath: allow force reload with no active paths

[Martin Wilck]

On Tue, 2020-03-24 at 16:03 -0500, Benjamin Marzinski wrote:
> If the partition information has changed on multipath devices (say,
> because it was updated on another node that has access to the same
> storage), users expect that running "multipathd reconfigure" will
> update
> that.  However, if the checkers for the multipath device are pending
> for
> too long when the the device is reconfigured, multipathd will give up
> waiting for them, and refuse to reload the device, since there are no
> active paths. This means that no kpartx update will be triggered.
> 
> Multipath is fully capable of reloading a multipath device that has
> no
> active paths. This has been possible for years. If multipath is
> supposed
> to reload the device, it should do so, even if there are no active
> paths.
> 
> Generally, when multipath is force reloaded, kpartx will be updated.
> However when a device is reloaded with no paths, the udev rules won't
> run kpartx.  But they also weren't running kpartx when the first
> valid
> path appeared, even though the dm activation rules get run in this
> case.
> This changes 11-dm-mpath.rules to run kpartx when a device goes from
> no
> usable paths to having usable paths.
> 
> Signed-off-by: Benjamin Marzinski <bmarzins at redhat.com>
> ---
>  libmultipath/configure.c    | 6 ------
>  multipath/11-dm-mpath.rules | 2 +-
>  2 files changed, 1 insertion(+), 7 deletions(-)

Reviewed-by: Martin Wilck <mwilck at suse.com>

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