[hobbit] Creating a fake, or combination, client

[Stef Coene]

On Tuesday 06 November 2007, Ward, Martin wrote:
> Hi all,
>
> I am a newbie to Hobbit and have inherited a working system. I have a
> good idea of how it all hangs together but now I want to produce certain
> graphs and cannot figure out how.
>
> I have a cluster of mail servers that run Postfix; each of these clients
> is monitored within Hobbit. In the Trends link for each client I have
> graphs showing the various mail queues (incoming, deferred etc) and this
> data is stored in RRD files on the Hobbit server.
>
> Is there a way within Hobbit of creating a false or meta- client that
> can have a graph with data from all of these RRD files? Particularly I
> would like a graph that has all the incoming mail queue sizes on it with
> one line per server. I already have this information in lots of
> different RRD files but would like to have them all in one graph. I can
> create a graph outside of Hobbit to do this, but within the monitoring
> system it restricts the RRD files it will display data from to those in
> the data directory of the selected client (in the Trends link).
>
> I have tried creating a new client in the data files ans symbolically
> linking the other RRD files into its data directory, but cannot persude
> the graphs to appear in the trends web page.
You can create a custom cluster aware client that runs on the servers.  The 
client uses an other client node to report.

An other possibility is to create in the rrd directory a new directory and 
create symlinks in this directory so each server has a symbolic link in this 
directory for the rrd that has the needed info.  Give each symlink an other 
name.
I use this to collect information of the CPU usage of lpars running on the 
same hardware box.  So I created a new directory and created symlinks to the 
vmstat.rrd files I need.  So in that directory I have a symlink named 
server-vmstat.rrd that points to ../server/vmstat.rrd.   And that for each 
server running on that hardware box.  To create the graphs, I added a new 
stanza to hobbitgraphs.cfg that parses the  *-vmstat.rrd files.  To access 
these graphs, you have to play with the url.  The host parameter is the name 
of the created directory and the service is the name of added stamza.  You 
don't a link from a hobbit page to this graph, but I already had 
a "handy-url-page" where I added a link to this graph.


Stef