From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Nelson Subject: Re: Advice for implementation of LED behavior in Ceph ecosystem Date: Wed, 01 Apr 2015 16:57:05 -0500 Message-ID: <551C69B1.9070100@redhat.com> References: <2C438B34CAC8264398F5C7AF7411910A6341F7EB@G4W3206.americas.hpqcorp.net> <551C6083.4070707@redhat.com> <551C693E.6020100@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.redhat.com ([209.132.183.28]:56992 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751690AbbDAV5K (ORCPT ); Wed, 1 Apr 2015 17:57:10 -0400 In-Reply-To: <551C693E.6020100@redhat.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: John Spray , "Handzik, Joe" , "ceph-devel@vger.kernel.org" On 04/01/2015 04:55 PM, John Spray wrote: > On 01/04/2015 22:17, John Spray wrote: >> Once you have found the block device and reported it in the OSD >> metadata, you can use that information to go poke its LEDs using >> enclosure services hooks as you suggest, and wrap that in an OSD >> 'tell' command (OSD::do_command). In a similar vein to finding the >> block device, it would be a good thing to have a config option here so >> that admins can optionally specify a custom command for flashing a >> particular OSD's LED. Admins might not bother setting that, but it >> would mean a system integrator could optionally configure ceph to work >> with whatever exotic custom stuff they have. > One more thought occurs to me -- one of the main cases where you'd want > to flash an LED would be to identify the drive of an OSD that is > down/out due to a dead drive. In that instance, the ceph-osd process > wouldn't actually be running, so you wouldn't be able to send it the > 'tell' to flash the LED. > > I guess in this interesting case you could either: > * Allow other OSDs on the same host to handle the 'tell blink' command > for the dead OSD's drive > * Leave this to calamari/whoever to read the dead OSD's block device > path from "ceph osd metadata", and go blink the LEDs themselves. > > Cheers, > John > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html It seems to me that the OSD potentially would flash the LED on it's way down if it thinks it's drive is dead/dying? Mark