MetricBeat is awesome..... 95% of information what we were getting in sigar metric is matching with the metricbeat output.... so we have started to use metric beat now....
However, some details like OS version Info are not included in the system module. This will add great value to identify what type of OS, Arch, IP, Vendor details, etc....
Is there any plugin available to get this info or any plans to include this in future release?