Description of problem:

Deployment of ceph-metrics fails at collectd stage because the service fails to start. This is displayed in the system journal:

Jan 09 11:52:26 MON0 collectd[16916]: plugin_load: plugin "python" successfully loaded.
Jan 09 11:52:26 MON0 collectd[16916]: plugin_load: plugin "threshold" successfully loaded.
Jan 09 11:52:26 MON0 collectd[16916]: plugin_load: plugin "aggregation" successfully loaded.
Jan 09 11:52:26 MON0 collectd[16916]: cephmetrics: Event messages enabled for target http://CLIENT0:8080/events/
Jan 09 11:52:26 MON0 collectd[16916]: Unhandled python exception in loading module: OSError: [Errno 13] Permission denied
Jan 09 11:52:26 MON0 collectd[16916]: Traceback (most recent call last):
Jan 09 11:52:26 MON0 collectd[16916]: File "/usr/lib64/collectd/cephmetrics/cephmetrics.py", line 129, in configure_callback
Jan 09 11:52:26 MON0 collectd[16916]: CEPH.probe()
Jan 09 11:52:26 MON0 collectd[16916]: File "/usr/lib64/collectd/cephmetrics/cephmetrics.py", line 51, in probe
Jan 09 11:52:26 MON0 collectd[16916]: self.iscsi = ISCSIGateway(self, self.cluster_name)
Jan 09 11:52:26 MON0 collectd[16916]: File "/usr/lib64/collectd/cephmetrics/collectors/iscsi.py", line 111, in __init__
Jan 09 11:52:26 MON0 collectd[16916]: self._root = RTSRoot()
Jan 09 11:52:26 MON0 collectd[16916]: File "/usr/lib/python2.7/site-packages/rtslib_fb/root.py", line 74, in __init__
Jan 09 11:52:26 MON0 collectd[16916]: mount_configfs()
Jan 09 11:52:26 MON0 collectd[16916]: File "/usr/lib/python2.7/site-packages/rtslib_fb/utils.py", line 438, in mount_configfs
Jan 09 11:52:26 MON0 collectd[16916]: stderr=subprocess.PIPE)
Jan 09 11:52:26 MON0 collectd[16916]: File "/usr/lib64/python2.7/subprocess.py", line 711, in __init__
Jan 09 11:52:26 MON0 collectd[16916]: errread, errwrite)
Jan 09 11:52:26 MON0 collectd[16916]: File "/usr/lib64/python2.7/subprocess.py", line 1327, in _execute_child
Jan 09 11:52:26 MON0 collectd[16916]: raise child_exception
Jan 09 11:52:26 MON0 collectd[16916]: OSError: [Errno 13] Permission denied
Jan 09 11:52:26 MON0 collectd[16916]: plugin_load: plugin "cpu" successfully loaded.
Jan 09 11:52:26 MON0 collectd[16916]: plugin_load: plugin "memory" successfully loaded.
Jan 09 11:52:26 MON0 collectd[16916]: plugin_load: plugin "interface" successfully loaded.
Jan 09 11:52:26 MON0 collectd[16916]: plugin_load: plugin "write_graphite" successfully loaded.
Jan 09 11:52:26 MON0 collectd[16916]: Error: Reading the config file failed!
Jan 09 11:52:26 MON0 collectd[16916]: Read the logs for details.
Jan 09 11:52:26 MON0 systemd[1]: collectd.service: main process exited, code=exited, status=1/FAILURE

In audit.log you can see that SELinux is blocking collectd from accessing resources:

[...]
type=AVC msg=audit(1515500056.751:5010): avc:  denied  { getattr } for  pid=25396 comm="gwcli" path="/usr/bin/rpm" dev="dm-0" ino=25314520 scontext=system_u:system_r:collectd_t:s0 tcontext=system_u:object_r:rpm_exec_t:s0 tclass=file
type=SYSCALL msg=audit(1515500056.751:5010): arch=c000003e syscall=4 success=no exit=-13 a0=2d79270 a1=7ffc0fa916b0 a2=7ffc0fa916b0 a3=7f6821e26610 items=0 ppid=25388 pid=25396 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=4294967295 comm="gwcli" exe="/usr/bin/python2.7" subj=system_u:system_r:collectd_t:s0 key=(null)
type=PROCTITLE msg=audit(1515500056.751:5010): proctitle=2F7573722F62696E2F707974686F6E002F7573722F62696E2F6777636C69002D76
type=AVC msg=audit(1515500056.818:5011): avc:  denied  { search } for  pid=25388 comm="collectd" name="/" dev="configfs" ino=7700 scontext=system_u:system_r:collectd_t:s0 tcontext=system_u:object_r:configfs_t:s0 tclass=dir
type=SYSCALL msg=audit(1515500056.818:5011): arch=c000003e syscall=6 success=no exit=-13 a0=55a7666312a0 a1=7ffe455935a0 a2=7ffe455935a0 a3=0 items=0 ppid=1 pid=25388 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=4294967295 comm="collectd" exe="/usr/sbin/collectd" subj=system_u:system_r:collectd_t:s0 key=(null)
type=PROCTITLE msg=audit(1515500056.818:5011): proctitle="/usr/sbin/collectd"
type=AVC msg=audit(1515500056.818:5012): avc:  denied  { execute } for  pid=25405 comm="collectd" name="mount" dev="dm-0" ino=25314940 scontext=system_u:system_r:collectd_t:s0 tcontext=system_u:object_r:mount_exec_t:s0 tclass=file
type=SYSCALL msg=audit(1515500056.818:5012): arch=c000003e syscall=59 success=no exit=-13 a0=55a7666312a0 a1=55a766631c50 a2=7ffe45595538 a3=0 items=0 ppid=25388 pid=25405 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=4294967295 comm="collectd" exe="/usr/sbin/collectd" subj=system_u:system_r:collectd_t:s0 key=(null)
type=PROCTITLE msg=audit(1515500056.818:5012): proctitle="/usr/sbin/collectd"
type=SERVICE_START msg=audit(1515500056.830:5013): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=collectd comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=failed'
[...]

Version-Release number of selected component (if applicable):

ceph-selinux-12.2.1-40.el7cp.x86_64
selinux-policy-targeted-3.13.1-166.el7_4.7.noarch
pcp-selinux-3.11.8-7.el7.x86_64
collectd-python-5.7.2-1.el7cp.x86_64
collectd-5.7.2-1.el7cp.x86_64
cephmetrics-collectors-1.0-7.el7cp.x86_64

cephmetrics-1.0-7.el7cp.x86_64
cephmetrics-ansible-1.0-7.el7cp.x86_64
cephmetrics-grafana-plugins-1.0-7.el7cp.x86_64


How reproducible:

Install ceph-metrics with SELinux enabled on the Ceph nodes.

Additional info:

collectd starts normally as soon as I temporarily disable SELinux: setenforce 0