Hi Wido, On 02/15/2017 05:59 PM, Wido den Hollander wrote: > Hi, > > Currently we can supply a OSD UUID to 'ceph-disk prepare', but we can't provide a OSD ID. > > With BlueStore coming I think the use-case for this is becoming very valid: > > 1. Stop OSD > 2. Zap disk > 3. Re-create OSD with same ID and UUID (with BlueStore) > 4. Start OSD > > This allows for a in-place update of the OSD without modifying the CRUSHMap. For the cluster's point of view the OSD goes down and comes back up empty. > > There were some drawbacks around this and some dangers, so before I start working on a PR for this, any gotcaches which might be a problem? > > The idea is that users have a very simple way to re-format a OSD in-place while keeping the same CRUSH location, ID and UUID. Since the mapping UUID <> id is kept in the monitor, re-using the UUID should give you the same OSD id. That is, unless your remove the OSD from the monitor but that's not what you're trying to do right ? Cheers -- Loïc Dachary, Artisan Logiciel Libre -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
