-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 You are close... I've done it by creating a new SSD root in the CRUSH map, then put the SSD OSDs into a -ssd entry. I then created a new crush rule to choose from the SSD root, then have the tiering pool use that rule. If you look at the example in the document and think of ceph-osd-ssd-server-1 and ceph-osd-platter-server-1 as the same physical server with just logical separation, you can follow the rest of the example. You will need to modify either the ceph.conf to have the ssd OSDs have a different CRUSH map location or write a location script to do it automatically [1]. ceph.conf example: [osd.70] crush location = root=ssd host=nodez-ssd To do it programmaticly, you can use /usr/bin/ceph-crush-location as a base. I extended it by finding the device, then searching through hdparam to see if the rotation was greater than zero. If it wasn't then I output the hostname with the ssd portion, otherwise just the hostname. It was only a few lines of code, but I can't find it right now. I was waiting for ACLs to be modified so that I could query the data center location from our inventory management system (that was a few months ago) and I'm still waiting. [1] http://lists.ceph.com/pipermail/ceph-users-ceph.com/2015-January/045673.html -----BEGIN PGP SIGNATURE----- Version: Mailvelope v0.13.1 Comment: https://www.mailvelope.com wsFcBAEBCAAQBQJVunMXCRDmVDuy+mK58QAAq04P+QH95haU34fWZ5PsPIxv oY7JReywHwP3mWBO2XkaIg/l4AYV/HCBckBTSyp+GGFAtMeVEndiHCYTUf+F kQJjIk1jZoN+WTLnD8nsfDMrmVmforyGcG4Y399C4cCkBmeoU3jeGeKx+Unx dxiW6flRH5GPCazQdAAbXgb8InynUZ/EqmTY0FCDuLQ3CEXELuM8IReKwz0X 9LYqVIV+tdE1Ff2nDnLQlYYVpVv5K0y4TXBj8JzYH/41XbEws2GQnhb6b8zW aopUDC9RsNGtzWf4RDg8X3LDHrw7IBtAuJf+PHbcq3Y4cmPf5Z0TYiS1bqn1 19kj3EhDVVdW1KUue2S3GemyP0+bIypA/VDGzFXgv9g5oKN0bXPOjuFKAD2Q 7Rc2yoW70LACgL0a2KiRPRt8e6Jz5/vG6GijZvxTTZfkDPKHBOPPA3mFyAS4 FGmu39/q5VP7V+CepaKjbGNUWRzlzOOcc4ybk3dmktYEFOTw4QZLczBGJ8s4 I+AdYDjiQOAG3n3xixqRFOb4URjfKOrUbnHfNVQJU+qfYfV1RBLThhRjiv0v O+oiKiWuugZicHniTfHuOYePgxbs9eU2Hk8VRVk9ievXuRynDrH7D+IeUzUJ JGoj01YM60Ul1XJPWatMoM+435hcHrGd0rJ3bi91DOrZmT55X4jjdUA8z/3Y xMZE =Tqaw -----END PGP SIGNATURE----- ---------------- Robert LeBlanc PGP Fingerprint 79A2 9CA4 6CC4 45DD A904 C70E E654 3BB2 FA62 B9F1 On Wed, Jul 29, 2015 at 9:21 PM, van <chaofanyu@xxxxxxxxxxx> wrote: > Hi, list, > > Ceph cache tier seems very promising for performance. > According to > http://ceph.com/docs/master/rados/operations/crush-map/#placing-different-pools-on-different-osds > , I need to create a new pool based on SSD OSDs。 > > Currently, I’ve two servers with several HDD-based OSDs. I mean to add one > SSD-based OSD for each server, and then use these two OSDs to build a cache > pool. > But I’ve found problems editing crushmap. > The example in the link use two new hosts to build SSD OSDs and then create > a new ruleset take the new hosts. > But in my environment, I do not have new servers to use. > Can I create a ruleset choose part of OSDs in a host? > For example, as the crushmap shown below, osd.2 and osd.5 are new added > SSD-based OSDs, how can I create a ruleset choose these two OSDs only and > how can I avoid default ruleset to choose osd.2 and osd.5? > Is this possible, or I have to add a new server to deploy cache tier? > Thanks. > > host node0 { > id -2 > alg straw > hash 0 > item osd.0 weight 1.0 # HDD > item osd.1 weight 1.0 # HDD > item osd.2 weight 0.5 # SSD > } > > host node1 { > id -3 > alg straw > hash 0 > item osd.3 weight 1.0 # HDD > item osd.4 weight 1.0 # HDD > item osd.5 weight 0.5 # SSD > } > > root default { > id -1 # do not change unnecessarily > # weight 1.560 > alg straw > hash 0 # rjenkins1 > item node0 weight 2.5 > item node1 weight 2.5 > } > > # typical ruleset > rule replicated_ruleset { > ruleset 0 > type replicated > min_size 1 > max_size 10 > step take default > step chooseleaf firstn 0 type host > step emit > } > > > > van > chaofanyu@xxxxxxxxxxx > > > > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com