Created attachment 1352076 [details]
Volumes dashboard

Description of problem:
Sometimes when I reboot my machines I run into problem with some panels that are unable to show any data. Last time it happened with `Volumes` dashboard but I think it sometimes happen with `Hosts` dashboard. 
There might be a problem with order of starting services.

Version-Release number of selected component (if applicable):
glusterfs-3.8.4-52.el7rhgs.x86_64
tendrl-collectd-selinux-1.5.3-2.el7rhgs.noarch
tendrl-node-agent-1.5.4-2.el7rhgs.noarch
tendrl-selinux-1.5.3-2.el7rhgs.noarch
tendrl-commons-1.5.4-2.el7rhgs.noarch
tendrl-gluster-integration-1.5.4-2.el7rhgs.noarch
tendrl-api-1.5.4-2.el7rhgs.noarch
tendrl-api-httpd-1.5.4-2.el7rhgs.noarch
tendrl-monitoring-integration-1.5.4-3.el7rhgs.noarch
tendrl-grafana-selinux-1.5.3-2.el7rhgs.noarch
tendrl-notifier-1.5.4-2.el7rhgs.noarch
tendrl-ansible-1.5.4-1.el7rhgs.noarch
tendrl-ui-1.5.4-2.el7rhgs.noarch
tendrl-grafana-plugins-1.5.4-3.el7rhgs.noarch

How reproducible:
30%

Steps to Reproduce:
1. Import cluster with volume consisting of 6 nodes.
2. Restart all nodes. (preferably at the same time with ansible)
3. Wait for the synchronization with grafana.
4. Check all dashboards and look for missing data.

Actual results:
Sometimes there are missing data in some charts that can not be loaded even after some time. Last time I was able to reproduce it with `Volumes` dashboard as seen on attached screenshot. Collectd service on server with grafana have failed. All other services are running. Running `# gluster volume info` returns valid volume info that the volume is started.

Expected results:
Grafana should display corresponding data even after reboot of nodes.

Additional info: