>If a ratio cannot be met, this is an error condition that would be reported So if you have a ratio 1:5, ceph-volume only works in auto if the number of disks are modulo 6 ? That's very restrictive. >> If we have several SSDs free, which one should be used ? > All of them But only if the ratio matches then. With a 2 SSD, 5 HDDs, the ratio 1:5 ratio match, which SSD is taken ? >> If we have multiple HDDs types (10/15K/7.2K) how be sure they are used in the same 'auto' setup ? >There is no distinction for HDDs other than size (and being rotational) So there is here a strong assomption that nodes doesn't mix hdd types. >> If we have 1 SSD and 1 NVMe, which one is preferred ? >They are treated the same While the performance allow a totally different ratio. So a precedence should be defined. >> When the user is providing a list of devices, do we agree that they have to be checked against the "rejecting" rules to avoid using a wrong device ? >We have some rules/checks that we would go through for devices. >However, most of these aren't even in place in ceph-volume today. For >example, we don't check if a raw device >is read-only, or if it is part of a removable media. We assume the >caller knows best. I think the function rejecting devices should be improved but also be shared between the auto mode and the user-defined mode. This way we get similar checks between both modes and guarantee no mistake are made. I'll offer a PR for that. -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
