>> >> There is a socket open to each OSD (object storage daemon). I’ve always understood that there were *two* to each OSD, was I misinformed? >> A Ceph cluster may have tens, hundreds or even thousands of OSDs (although the >> latter is rare -- usually folks end up with several smaller clusters >> instead a single large cluster). … though if a client has multiple RBD volumes attached, it may be talking to more than one cluster. I’ve seen a client exhaust the file descriptor limit on a hypervisor doing this after a cluster expansion. >> A thing to note is that, by default, OSD sessions are shared between >> RBD devices. So as long as all RBD images that are mapped on a node >> belong to the same cluster, the same set of sockets would be used. Before … Luminous was it? AIUI they weren’t pooled, so older releases may have higher consumption. >
