Ceph » CephFS

I do path restriction follow：http://docs.ceph.com/docs/master/cephfs/client-auth/

[root@node181 ~]# ceph auth get-or-create client.foo mon 'allow r' mds 'allow r, allow rw path=/bar' osd 'allow rw pool=data'
[client.foo]
        key = AQBGpqFXTCDnJhAAdF1TNwBFQVo0gAT8ce2gFg==

But with the following error when mount

[root@node181 ~]# ceph-fuse -n client.foo /root/mycephfs -r /bar
2016-08-03 16:13:02.449385 7f0d24b27e80 -1 init, newargv = 0x7f0d3035dd30 newargc=11
ceph-fuse[13696]: starting ceph client
2016-08-03 16:13:02.449739 7f0d24b27e80 -1 auth: unable to find a keyring on /etc/ceph/ceph.client.foo.keyring,/etc/ceph/ceph.keyring,/etc/ceph/keyring,/etc/ceph/keyring.bin: (2) No such file or directory
2016-08-03 16:13:02.449754 7f0d24b27e80 -1 monclient(hunting): ERROR: missing keyring, cannot use cephx for authentication
ceph-fuse[13696]: ceph mount failed with (2) No such file or directory
ceph-fuse[13694]: mount failed: (2) No such file or directory

if I add generated files into the /etc/ceph/ceph.client.*client_name*.keyring,
it's mount successful

[root@node181 ~]# ceph auth get-or-create client.foo mon 'allow r' mds 'allow r, allow rw path=/bar' osd 'allow rw pool=data' > /etc/ceph/ceph.client.foo.keyring

[root@node181 ~]# ceph-fuse -n client.foo /root/mycephfs -r /bar
2016-08-03 16:19:28.294400 7f753f114e80 -1 init, newargv = 0x7f7548c0bd30 newargc=11ceph-fuse[13914]: starting ceph client

ceph-fuse[13914]: starting fuse