I've used a crush location hook script to handle this before device classes existed. It checked the device type on startup and assigned the crush position based on this. I don't have that crush map any longer anywhere but the basic version of it looked like this: two roots "hdd" and "ssd". The hdd roots had servers with their hostname in it and the ssd root had buckets of type host "-ssd" appended to the hostname (for a reason I don't remember). At some time someone consolidated the two roots under yet another root because some tool (I think it might have been proxmox?) couldn't handle separate roots, especially if none of them was named "default". We then had two roots within another bucket of type root which (surprisingly) worked and is probably a weird edge case. Probably not too helpful because I don't have any IDs or anything left from that era... Paul Am Sa., 22. Sep. 2018 um 00:39 Uhr schrieb Sage Weil <sweil@xxxxxxxxxx>: > > Hi everyone, > > In luminous we added the crush device classes that automagically > categorize your OSDs and hdd, ssd, etc, and allow you write CRUSH rules > that target a subset of devices. Prior to this it was necessary to make > custom edits to your CRUSH map with parallel hierarchies for each > OSD type, and (similarly) to disable the osd_crush_update_on_start option. > > As Dan has noted previously, transitioning from a legacy map to a modern > one using classes in the naive way will reshuffle all of your data. He > worked out a procedure do do this manually but it is delicate and error > prone. I'm working on a tool to do it in a robust/safe way now. > > However... I want to make sure that the tool is sufficiently general. > Can anyone/everyone who has a customized CRUSH map to deal with different > OSD device types please send me a copy (e.g., ceph osd getcrushmap -o > mycrushmap) so I can test the tool against your map? > > Thanks! > sage > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com -- Paul Emmerich Looking for help with your Ceph cluster? Contact us at https://croit.io croit GmbH Freseniusstr. 31h 81247 München www.croit.io Tel: +49 89 1896585 90 _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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