[collectd] Strange behaviour of collectd with rrdcached

[Marc]

Hello  


On Friday 12 December 2014 at 11:00, Marc wrote:

> Hello all  
>  
> I’m facing issues when using collectd alongside rrdcached: cached metrics don’t get written to disk, and I get a bunch of the following errors:
>  
> rrdcached plugin: rrdc_update (/var/lib/collectd/rrd/test_collectd/cpu-0/cpu-interrupt.rrd, [1418377171:3440], 1) failed with status -1.
> Filter subsystem: Built-in target `write': Dispatching value to all write plugins failed with status -1.
>  
>  
> The configurations used for this setup are:
>  
> ### collectd client node:
> FQDNLookup false
> Hostname "test_collectd"
> BaseDir "/var/lib/collectd"
> PluginDir "/usr/lib/collectd"
> Interval 10
> LoadPlugin cpu
> LoadPlugin load
> LoadPlugin memory
> LoadPlugin network
> <Plugin network>
> Server “collectd-server" "25827"
> </Plugin>
>  
>  
>  
> ### collectd server node
> FQDNLookup false
> Hostname "collectd-server"
> BaseDir "/var/lib/collectd"
> PluginDir "/usr/lib/collectd"
> Interval 30
> LoadPlugin network
> <Plugin network>
> Forward true
> Listen "0.0.0.0" "25827"
> </Plugin>
> LoadPlugin rrdcached
> <Plugin rrdcached>
> DaemonAddress “collectd-server:42217"
> DataDir "/var/lib/collectd/rrd"
> CreateFiles true
> CollectStatistics false
> </Plugin>
>  
>  
>  
> ### /etc/default/rrdcached variables:
> OPTS="-l 10.90.x.y -w 300 -z 120 -j /var/lib/rrdcached/journal”
>  
> The strange thing is: rrdcached actually creates the files, but never updates them afterwards (even after the flushing timeout). I’ve used collectd+rrdcached a few years ago and they worked fine together, but I’m presently quite confused by this issue. I’ve strace’d all the processes but found nothing suspicious.
>  
> Versions used:
> - collectd 5.4.0 (tested with 5.1.0, same behaviour)
> - rrdcached 1.4.7
>  


I’ve performed multiple variations of my setup, and it turns out I can only make it work using a UNIX socket instead of a TCP socket…

Looks like I’m not the only one to have this issue: http://munin-monitoring.org/ticket/1117 but I haven’t got this error message (maybe Munin-specific).

m.