Grafana Introduction¶
This notebook describes the basic mechanisms for navigating Grafana dashboards. Grafana provides a detailed overview of how to use dashboards at https://grafana.com/docs/grafana/latest/dashboards/use-dashboards/
Finding Dashboards¶
Note that dashboard availability and names may not match those shown here.
Some featured dashboards can be quickly accessed from the front page of the Public, https://public-metrics.fabric-testbed.net or Infrastructure, https://infrastructure-metrics.fabric-testbed.net metric websites.
To browse the complete list of available dashboards open, the side menu by clicking on the hamburger (three horizontal lines) to the right. Then choose Dashboards.
This will take you to a list of all the dashboards. Click on a dashboard name to go to the dashboard.
Some dashboards are collections of other dashboards. Click on the Featured Dashboards to see a the list of dashboards that are accessible from the site's front page. These dashboards will have more information about them on the links from the front page.
To quickly search for dashboards use the Search or jump to.... text box at the top-center of the page.
Click on a result to go to the dashboard.
Using Drop Down Variables¶
Many of the dashboard views can be customized by choosing variables that affect the queries used to display the data. These drop downs are located in the upper left of the dashboards.
The Rack drop down is used on many dashboards. It allows the selection of which rack(s) are included in the queries. A rack is a FABRIC site (aka hank). Site names are abbreviations of 3 or 4 lower case characters. Select the checkboxes of sites you want to be represented in the graph.
The Host drop down is used on many dashboards. It allows the selection of which host(s) are included in the queries. Host values may change depending on the dashboard. In this example, the host names are for FABRIC nodes. They are labled by site name - hn (head node) or w# (worker node).
Some drop downs have pre-set options, but can also accept user input. Type in the value you want if it is not available in the drop down list.
Selecting Time Range¶
Dashboards generally have two types of data - instant or range values.
- Instant values are single values taken at a specific time.
- Range values are a set of values covering a given time span.
The time picker drop down allows the selection of the time period you want to display.
It shows the current selected value.
Selecting the drop down will give you a quick list on the right of common values you may choose. These values are relative times in relation to the current time.
You may also choose to set an Absolute time range. Selections can be made using the calendar picker, or typed in precisely in the From and To boxes.
The times shown usually default to the browsers time zone. Note that all FABRIC racks and metric collections always use UTC, therefore all the rack times will be in the same time zone. If you choose a rack in California, one in New York and one in Europe all the times are recored in UTC. When they are displayed, all the times will be shifed to the same time zone you have selected.
Auto Refresh¶
If you have picked a relative time range, you may also choose a refresh rate. Since most metrics are collected at a 30 second rate, anything less than 30 seconds will not be effective and just use more resources. The Auto setting will adjust the refresh rate to match what is visible in the graph. If the resolution allows you to see 5 seconds of data, then the refresh will be set to 5 seconds, etc...
If you have choosen an absolute time range, the refresh will be turned off.
Viewing Panels¶
Dashboards are composed of panels. Panels may contain a variety of data and visualizations. Some dashboards have lots of panels and you may just want to focus on one. Some panels may have dense data and you may want to get a better view.
View Single Panel¶
To select a single panel for viewing, use the three dots menu in the upper right of the panel. Select View . You may also hover the mouse over the panel and type'v'.
Select Visible Data¶
Some graphs can contain "too much" data. The data can be reduced by using some of the drop down variables. In this case you could reduce the data using the drop down and selecting just the rack in which you are interested.
Alternatively, if you are interested in picking out a certain graph line, such as this peak at worker node 2 at mass, you can select that node using the list of nodes ot the right.
The selected nodes will be highlighted in the list.
If you would like to see multiple graph lines, you can use control-click to select/unselect multiple nodes.
Zooming / Narrowing/Expanding Time Range¶
Zooming in by choosing a narrower time range can be done quickly by right clicking and dragging across the section of the graph you want to examine more closely.
Now the graph has gone from a relative time range of 24 hours to an absolute time range covering the selected area.
You can continue to zoom in narrowing the time range.
Now you can easily see the individual data points. Hover over the points to bring up the tooltip with the exact value.
To Zoom out, use the eye glass with the minus sign to the right of the time drop down.
Now the time range has expanded.
