weird chart

[firque]

does anybody know why my ping chart look like the screenshot in the attachment
it used to be a straight line but now it is dotted which makes it hard to read it

[star009]

You can try to change zoom

[Zaniwoop]

It is missing data.

This can be from the not enough pollers, or maybe the item switching to an unsupported state due to other factors.

[nelsonab]

As Zaniwoop said this is due to missing data, but what's going on under the hood is a little more involved.

Basically this is a timeout issue. You have an item configured in Zabbix to poll an item every N seconds (say 30 seconds), but you are actually getting data in to the Zabbix server at a rate > N (Let's say 2N, 60 seconds). When Zabbix goes to draw the graph it thinks that there has been a discontinuity in the data and thus will not connect two data points if their gap is above a threshold which is a multiple of the polling interval.

Have a closer look at the item, is every other call to it timing out? If that is the case increasing the time interval may not fix your problem as it may not fix the underlying problem. You could also consider increasing the connection timeout values in the Agent and Server config files, however this should be done as a last option as you may introduce unintended performance issues later.

If you are using a UserParameter or some other custom parameter (system.run)which can take a long time to execute consider breaking the data collection into a few pieces. Consider having a process run via cron or something similar which dumps the monitoring data to a text file, then use grep or similar tools to pull the needed data.