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

[Shawn Heisey]

On 3/23/2016 3:29 AM, Jeremy Laidman wrote:
> On Wed, Mar 23, 2016 at 8:17 PM Shawn Heisey <haproxy at elyograg.org
> <mailto:haproxy at elyograg.org>> wrote:
>
>     All four of these lines have been in the config for a long time,
>     but the
>     mule_aps and mule_nwsi tracking identifiers *used* to be ajp, the same
>     as the 8009 port line.  So I had three lines all using "ajp" as the
>     tracking ID.
>
>
> I think this explains it.  RRD only permits one update per (by
> default) 5-minute interval, and any subsequent ones are rejected.  If
> you had 3 updates going on every 5 minutes, only the first would have
> been accepted.  So if mule_aps or mule_nwsi were both reporting NaN
> then it's possible that only 1/3 or all updates had valid data.  Your
> graph seems to show about 1/3 present, and 2/3 missing.

Confirmed.  Thank you to everyone who responded with ideas.

Since I changed the config so each tracking ID is only used once per
config stanza, the graphing has been superb.  I wasn't the one who
created these configs. I just happened to be creating some additional
port monitoring and changing the TEXT attribute on the existing
"listening" config to include the port number.  Because I was already
making changes to a lot of PORT config lines, I decided to revamp them
all to more accurately reflect what we were monitoring.  I didn't even
realize I was fixing a problem. :)

Thanks,
Shawn