BST to GMT time change and problem with some graphs

[chrisfb]

Zabbix 2.0.6


Hi,

We have number of graphs which are related to some activities during the day. We have number of triggers set to alert us when number of events is not roughly the same as the average over number of lasts 1/5/10 weeks.
As we have now moved from BST to GMT our current number of events is shifted 1h as those events are somewhat related to the time of the day.

We have discussed this internally and we have few choices here:

- Run full Zabbix always in GMT
- Run some parts of Zabbix in GMT (mainly DBforBIX stuff) – is that possible?
- Make Zabbix to shift graphs somehow
- Use some option in Zabbix which we are not aware of to alert accordingly
- Take different approach

I would appreciate all input/feedback/ideas you might have. I’m sure that others are faced with similar issues (web monitoring?)

Please see attached picture for better understanding of our graphs:



Many thanks in advance
Chris

[steveboyson]

So the data for the blue, green and pink lines are from a different time zone? Or are they always GMT?

[chrisfb]

Hi,

Sorry for the late reply... Busy with operational issues!

I think that it would be best to explain this graph:

Red Line - number of events this week, after time change from BST to GMT

- as you can see, the number of events has sharply increased from around 8ish in the morning.

- That was the case in previous weeks as well, but now, as we have moved from Summer Time Zone to Winter Tome Zone, data for previous weeks is one hour behind which makes it look like number of events picks up around 7AM...

Green Line - number of events over past week (which - when I took that screenshot, was before time change)

Pink Line - number of events over past 5 weeks (which - when I took that screenshot, was before time change)

Blue Line - number of events over past 10 weeks (which - when I took that screenshot, was before time change).

Hope that helps in better understanding our problem here.

Many thanks in advance.
Chris

[steveboyson]

So that means that the screenshot shows data from values in different timezones but meanwhile they are all again in one timezone?

Sorry, then I do not understand the problem. Mea culpa.

[steveboyson]

I mean, it will be leveling out sometimes soon.

And in my personal opinion, it shows the correct values:
(show me the last XXX values when it was 8 o'clock, no matter what timezone 8 o'clock is. Compare it to the last XXX values 5 weeks earlier/later at 8 o'clock. Show these in a diagramm)

Do you rely on the EXACT values on a certain point in time? Then zabbix is definitely not the right tool since the graphs are rounded and the curves are more or less calculated.

[chrisfb]

Hi,

Thanks for your time. I would like to comment on few points:

In my initial question I've asked what are our options with graphs related to number of events at specific time after TIME CHANGE. I understand how this work and why they are "not aligned" or shifted but business needs those graphs to be correlated to the time of the day. I've also stressed that we do averages and that number of events is correlated to the time of the day... And that after 10 weeks everything will be OK until the next time change!

In other words, I understand what's the problem here but the requirement is:

"Please create an alert if number of events today at 1PM is not close to the number of events in the last 5/10 weeks at 1PM".

Anyway, I'm wondering how people deal with this kind of "problem" - surely we are not unique in this- do they always run Zabbix in GMT for example without time changes? What about if they have servers in different time zones doing the same thing? Do you just not alert on time-specific number of events? Is there a way to have some graphs in the same time zone always? Is there different, better, way of achieving the same? I feel like I'm in the box and I would appreciate some out of the box ideas. :-)

Here are the options which I've listed in my initial question:

- Run full Zabbix always in GMT
- Run some parts of Zabbix in GMT (mainly DBforBIX stuff) – is that possible?
- Make Zabbix to shift graphs somehow
- Use some option in Zabbix which we are not aware of to alert accordingly
- Take different approach


I'm keen to get any input how this could be done as clearly we are doing something wrong here...

Many thanks in advance.
Chris

[steveboyson]

Even if I get your point (and that of your business department): but 1PM is 1PM.
It seems they don't care about timezones. So why should you? ;-) ;-)

Of course you can write an external script which checks the time delta.
Then you'd better store your values externally and not within zabbix. With some time manipulation you should be able to check if a certain date lies in summer or winter time and react accordingly by adding or subtracting the correct offset.

Regarding your options: if you don't want to do it externally then the "all in GMT" option seems to be the least invasive way IMHO.

For DBforBIX I'm missing any knowledge.
Shifting zabbix' graphs seems not possible to me.
And I do not know any other options.