Duplicate entries for prometheus rbd exporter

[y4ns0l0]

Description of Issue/Question

/var/log/messages on my admin node was full of this kind of messages :

2019-02-19T00:14:54.817283+01:00 yval1950 node_exporter[2289515]: * collected metric ceph_rbd_image_bytes_provisioned label:<name:"cluster" value:"ceph" > label:<name:"image" value:"7d7b066f-01aa-4ea6-a399-50c7347e51f5" > label:<name:"pool" value:"glance" > gauge:<value:2.147483648e+10 >  was collected before with the same name and label values
2019-02-19T00:14:54.817481+01:00 yval1950 node_exporter[2289515]: * collected metric ceph_rbd_image_bytes_provisioned label:<name:"cluster" value:"ceph" > label:<name:"image" value:"7d9ccffe-46a6-40eb-818a-7b00d1bd4c3a" > label:<name:"pool" value:"glance" > gauge:<value:8.589934592e+09 >  was collected before with the same name and label values
2019-02-19T00:14:54.817681+01:00 yval1950 node_exporter[2289515]: * collected metric ceph_rbd_image_bytes_provisioned label:<name:"cluster" value:"ceph" > label:<name:"image" value:"802baca5-80ea-4269-ba60-22f3da060a98" > label:<name:"pool" value:"glance" > gauge:<value:2.361393152e+09 >  was collected before with the same name and label values
2019-02-19T00:14:54.817878+01:00 yval1950 node_exporter[2289515]: * collected metric ceph_rbd_image_bytes_provisioned label:<name:"cluster" value:"ceph" > label:<name:"image" value:"80a5874f-4af9-4acc-89c2-566dedb1437f" > label:<name:"pool" value:"glance" > gauge:<value:4.831838208e+10 >  was collected before with the same name and label values

It seems that rbd exporter cron script /var/lib/prometheus/node-exporter/rbd.sh is generating one similar entry for each volume and its snapshots. For example this volume :

rbd du cinder/volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a
NAME                                                                                      PROVISIONED    USED
volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a@snapshot-c91c77b4-fc85-4857-9a9c-79c0b1ed91ac      200GiB 94.1GiB
volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a@snapshot-cbcf0289-9644-4b64-a750-bf0e78d31497      200GiB      0B
volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a@snapshot-c8b1822d-9f4c-4deb-b872-0e59124f8954      200GiB 10.5GiB
volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a                                                    200GiB 11.5GiB
<TOTAL>                                                                                        200GiB  116GiB

will produce:

ceph_rbd_image_bytes_used{image="volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a",snapshot="snapshot-c91c77b4-fc85-4857-9a9c-79c0b1ed91ac",cluster="ceph",pool="cinder"} 101040783360
ceph_rbd_image_bytes_provisioned{image="volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a",snapshot="snapshot-c91c77b4-fc85-4857-9a9c-79c0b1ed91ac",cluster="ceph",pool="cinder"} 214748364800
ceph_rbd_image_bytes_used{image="volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a",snapshot="snapshot-cbcf0289-9644-4b64-a750-bf0e78d31497",cluster="ceph",pool="cinder"} 0
ceph_rbd_image_bytes_provisioned{image="volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a",snapshot="snapshot-cbcf0289-9644-4b64-a750-bf0e78d31497",cluster="ceph",pool="cinder"} 214748364800
ceph_rbd_image_bytes_used{image="volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a",snapshot="snapshot-c8b1822d-9f4c-4deb-b872-0e59124f8954",cluster="ceph",pool="cinder"} 11228151808
ceph_rbd_image_bytes_provisioned{image="volume-c718dd75-b6f5-4680-b3b4-e962b96b6a6a",snapshot="snapshot-c8b1822d-9f4c-4deb-b872-0e59124f8954",cluster="ceph",pool="cinder"} 214748364800

Steps to Reproduce Issue

Create a snapshot on a volume and observe duplicated entries in /var/lib/prometheus/node-exporter/rbd.prom

Versions Report

deepsea 0.8.6
salt-master 2018.3.0 (Oxygen)
salt-minion 2018.3.0 (Oxygen)

[y4ns0l0]

Here is a fix #1540