Christian; What is your failure domain? If your failure domain is set to OSD / drive, and 2 OSDs share a DB / WAL device, and that DB / WAL device dies, then portions of the data could drop to read-only (or be lost...). Ceph is really set up to own the storage hardware directly. It doesn't (usually) make sense to put any kind of RAID / JBOD between Ceph and the hardware. Thank you, Dominic L. Hilsbos, MBA Director - Information Technology Perform Air International Inc. DHilsbos@xxxxxxxxxxxxxx www.PerformAir.com -----Original Message----- From: Christian Wahl [mailto:wahl@xxxxxxxx] Sent: Thursday, February 27, 2020 12:09 PM To: ceph-users@xxxxxxx Subject: SSD considerations for block.db and WAL Hi everyone, we currently have 6 OSDs with 8TB HDDs split across 3 hosts. The main usage is KVM-Images. To improve speed we planned on putting the block.db and WAL onto NVMe-SSDs. The plan was to put 2x1TB in each host. One option I thought of was to RAID 1 them for better redundancy, I don't know how high the risk is of corrupting the block.db by one failed SSD block. Or should I just one for WAL+block.db and use the other one as fast storage? Thank you all very much! Christian _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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