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graphmonitoringzabbix

When does Zabbix display graph lines connected?

When Zabbix graphs show items with missing values, the graph line is shown interrupted:

Line interruped

In my eyes this shall show visually that there aren't any values between 5:25 and 5:55. This seems completely correct.

But I have another graph where the line between the values before and after the gap are displayed connected:

Line connected

Both graphs are using different items (but in this case the same or similiar values). Both items don't have values from about 5:25 to 5:55. Both graphs are equally configured - as far as I can see...

What is the difference? Why is the second line displayed connected?

I also tried different draw styles (Line, filled region etc.) as described in Zabbix docu Custom graphs - always the same. Zabbix seems to have some other criteria to decide if the graph should be shown connected or interrupted.

Solution

  • This depends on item type, item interval configuration and the graph width.

    • item type - for trapper items, a line will always be drawn from one value to the next, and a straight line to the graph edge
    • item interval configuration and graph width - depending on how frequently the values are collected, how many are missing and how long the gap would be pixel-wise

    Note that I said "item interval configuration" - flexible intervals and item scheduling can affect this in other, sometimes quite obscure, ways.