From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bill Nottingham Date: Wed, 02 Jul 2008 15:15:27 +0000 Subject: triggering udev rules based on the state of udevd Message-Id: <20080702151527.GA22892@nostromo.devel.redhat.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org When using udev to automatically assemble MD devices (using mdadm --incremental), we've come across the following conundrum: - If you just pass --incremental to mdadm, devices will only be started when all members are present; you can never start a degraded device) - If you pass --run (to solve this), devices will be started when the minimum # of devices is present. This causes the array to always start in degraded mode, causing unnecessary resyncs. There doesn't seem to be a good happy medium that allows for degraded assembly when needed, but normal assembly in most cases. One potential way to do this would be to queue events such as these RAID-handling events as 'idle', or 'end of queue', such that they are always run at the end of queue after other events have run. Is that sort of thing possible? Bill