[ceph-users] Re: classes crush rules new cluster

Or, just reassign one existing OSD to the new class.

...

...

Note that testing this rule with crushtool won't work here since the fake OSD isn't assigned to a hosts.

...

But what's the point in having a rule without the corresponding devices? You won't be able to create a pool with that rule anyway until the OSDs are present.

There is that.

Yes indeed so you can prepare creating all rules and pools before you have added the osds. Especially handy if you have a few shell commands you paste.