Re: [libvirt] [PATCH] storage_backend_rbd: always call rados_conf_read_file when connect a rbd pool

> > Could you provide a bit more context... > > Why does calling rados_conf_read_file with a NULL resolve the issue? > > Is this something "new" or "expected"? And if expected, why are we only > seeing it now? > > What is the other thread that "has" the lock doing? It seams that the server side of ceph does not response our request. So when libvirt call rbd_open/rbd_list, etc, it never return. But qemu works fine. So I take qemu's code as a reference. https://github.com/qemu/qemu/blob/master/block/rbd.c#L365 rados_conf_read_file with a NULL will try to get ceph conf file from /etc/ceph and other default paths. Althougth we rados_conf_set in the following code, w/o rados_conf_read_file, ceph-0.94.7-1.el7 does not answer our rbd_open. Some elder or newer ceph server does not have this issue. I think this may be a ceph server bug of ceph-0.94.7-1.el7.

Doing rados_conf_read_file(cluster, NULL) will make our code more robust. Regards, - Chen