> I run a couple of gmond's and one gmetad in a common subnet.
> How can I make the gmetad talk to another gmetad, running in another
> subnet. I want to operate a central web server outside my farm.
> Within the subnet everything, incl. the web-frontend, works fine.
>
> I guess the gmond's (/etc/gmond.conf) do not have to know about the
> second gmetad? It's all in /etc/gmetad.conf?
gmetads can be data sources to other gmetads, as long as they are trusted
and such. That part should be fairly straightforward - I've done it to
hierarchically 'arrange' different clusters within our "Grid"/VO. Have you
run into problems doing this, or are you still at the conceptual level here?
I will note that I don't do this at the moment because I encountered very
very severe data loss. I was running three gmetads (two subordinate to one
"master") on a machine with a web frontend for each. A rough sketch:
gmetad
-|-gmetad (local)
| |
| --128 node cluster (gmond remote)
| --50 node cluster (gmond remote)
| --32 node cluster (gmond remote)
|
|
|-gmetad (local)
| |
| --4-6 node cluster (gmond local)
|
|-remote gmond for a 10 node cluster
I think it has something to do with the timestamping issues being discussed
on the dev list, but for now I just run the single gmetad querying all the
gmonds directly, and it's fine (albeit uglier).
The problem I refer to is the RRD_Update getting double updates for a single
timestamp, i.e. the rrd delta was too small being 0 seconds. The debug
output showed "RRD_update: illegal attempt to update using time [NNNN] when
last update time is [same-NNNN] (minimum one second step)" every minute or
so, with corresponding lack of data in the graphs. Hope that'll be fixed in
2.5.4 so I can run this stuff properely. :)
--
Ken MacInnis - System Research Programmer II - MGrid
130 CCAB, 1071 Beal Ave, Ann Arbor, MI 48109
kmacinni at umich dot edu - +1 734 647 8307 (w) - +1 734 936 4919 (f)
