[Xymon] "ports" RRD graph is often flaky.

[J.C. Cleaver]

On Tue, March 22, 2016 3:46 pm, Shawn Heisey wrote:
> I see several graphs like this in xymon (4.3.23), where at least one of
> the port graphs (configured in analysis.cfg) has lots of data points
> missing:
>
> https://www.dropbox.com/s/l483lilzh5n610k/flaky-xymon-port-graph.png?dl=0
>
> Any idea how I can fix this?  As you can see, the red line for http has
> data for the entire graph, while the blue line for ajp is very spotty.
> I just added the last two monitors less than an hour ago, so I don't
> have history on those yet.
>
> This is not unique to this host.  As far as I can tell, the port
> listings coming back from the client are always good, even when the
> graph has no line.
>
> Thanks,
> Shawn

This is interesting. When you zoom in on an area without data, are you
getting NaN or 0's? I might suspect something is aborting processing here,
but it's probably safe to rule out a message transmission issue, since
both the client log this is coming from and the resulting ports 'data'
message are unified blocks.

Q's:
* Are there any errors in xymond_client's or xymond_rrd's logs around
these times?
* Is there a chance something else might be reporting netstat info on this
hostname?
* Have there been any modifications to the client-side script for this
server?
* Are you seeing the behavior from other clients? (Just AJP)
* Do the 'trends' graphs for this client show any other issue occurring
concurrently with the gaps? (Missing vmstat data, for example, or process
counts)

Finally, can you include your PORTS sections from analysis.cfg for this
server?


-jc