Hi, all I wanna fetch debug librbd and debug rbd logs when I am using vm to read / write. Details: I created a volume from ceph and attached it to a vm. So I suppose when I do read/write in the VM, I can get some rbd debug logs in the host where the vm lies in. But in fact, after everything I can try, I still cannot get those logs. Below is the configuration on qemu side ;global [global] ; allow ourselves to open a lot of files max open files = 131072 auth cluster required = none auth service required = none auth client required = none ; set log file log file = /var/log/ceph/$name.log ; set up pid files pid file = /var/run/ceph/$name.pid ;client [client] rbd cache = true rbd cache size = 21474836480 rbd cache max dirty = 0 ; set qemu log file log file = /var/log/ceph/ceph.client.log # debug ms = 1 # debug client = 20 debug rbd = 20 debug librbd = 20 debug objectcacher = 20 ; monitors ; You need at least one. You need at least three if you want to ; tolerate any node failures. Always create an odd number. [mon] mon data = /data/$name [mon.Ceph-N3] host = node3 mon addr = 192.168.1.13:6789 Something I tried: I do can fetch librbd logs when using rbd command like "rbd list pool_name" and " rbd -p pool_name bench-write image_name --io-size 4096 --io-threads 1 --io-total 4096 --io-pattern rand" But if I using dd in vm to the virtual volume created by ceph, there is still no rbd debug logs. Hopefully I have already made myself clear, and I really need some help. Best regards, Chendi _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com