There are plenty of posts in this list. Please search a bit. Example threads are: What's the best practice for Erasure Coding large concurrent rbd operations block for over 15 mins! Can't create erasure coded pools with k+m greater than hosts? And many more. As you will see there, k=2,m=1 is bad and so is k=7. You should also refer to the ceph documentation about failure domains and EC pools, which will explain the possible reasons why your 7+2 pool does not work. The answers are not easy, depend on your hardware and you will have to do some work testing and benchmarking. Best regards, ================= Frank Schilder AIT Risø Campus Bygning 109, rum S14 ________________________________________ From: ceph-users <ceph-users-bounces@xxxxxxxxxxxxxx> on behalf of John Hearns <hearnsj@xxxxxxxxxxxxxx> Sent: 24 October 2019 08:21:47 To: ceph-users Subject: Erasure coded pools on Ambedded - advice please I am setting up a storage cluster on Ambedded ARM hardware, which is nice! I find that I can set up an erasure coded pool with the default k=2,m=1 The cluster has 9x OSD with HDD and 12xOSD with SSD If I configure another erasure profile such as k=7 m=2 then the pool creates, but the pgs stick in configuring/incomplete. Some advice please: a) what erasure profiles do people suggest for this setup b) a pool with m=1 will work fine of course, I imagine though a failed OSD has to be replaced quickly If anyone else has Ambedded, what crush rule do you select for the metadata when creating a pool? _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com