Ganglia No matching metrics detected

Question

We are getting error as "No matching metrics detected". cluster level metrics are visible.

ganglia core 3.6.0 ganglia web 3.5.12

Please help to resolve this issue.

Regards, Jayendra

Answer 1

Somewhere, in a .conf file (or .pyconf, et al,) you must specify a 'collection_group' with a list of the metrics you want to collect. From the default gmond.conf, it should look similar to this:

collection_group {
  collect_once = yes
  time_threshold = 1200
  metric {
    name = "cpu_num"
    title = "CPU Count"
  }
  metric {
    name = "cpu_speed"
    title = "CPU Speed"
  }
  metric {
    name = "mem_total"
    title = "Memory Total"
  }
}

You may use wildcards to match the name.
You'll also need to include the module that provides the metrics you are looking to collect. Again, the example gmond.conf contains something like this:

modules {
  module {
    name = "core_metrics"
  }
  module {
    name = "cpu_module"
    path = "modcpu.so"
  }
}

among others.

You can generate an example gmond.conf by typing

gmond -t > /usr/local/etc/gmond.conf

This path is correct for ganglia-3.6.0, I know that many file paths have changed several times since 3.0...

A good reference book is 'Monitoring with Ganglia.' I'd recommend getting a copy if you're going to be getting very deeply involved with configuring / maintaining a ganglia installation.

Answer 2

When summary/cluster graphs are visible, but individual host graph data is not, this might be caused by a mismatch of hostname case (between reported hostname and rrd graph directory names).

1. Check /var/lib/ganglia/rrds/CLUSTER-NAME/HOSTNAME This will show you what case the hostnames are getting their graphs generated as.
2. If the case does not match their hostname, edit: /etc/ganglia/conf.php (this allows overrides to defaults at: /usr/share/ganglia/conf_default.php)

3. Add the following line:

   $conf['case_sensitive_hostnames'] = false;

4. Another place to check for case sensitiviy is the gmetad settings at /etc/ganglia/gmetad

   case_sensitive_hostnames 0

Versions This Was Fixed On:

• OS: CentOS 6
• Ganglia Core: 3.7.2-2
• Ganglia Web: 3.7.1-2
• Installed via EPEL