[Metricbeat][System] Use aggregated fields in the visualizations for Diskio and Network

[herrBez]

Describe the enhancement:

As of now the visualizations:

• Disk IO (Bytes) [Metricbeat System] ECS
• Network Traffic (Bytes) [Metricbeat System] ECS
• Network Traffic (Packets) [Metricbeat System] ECS

use per-disk/per-network-interface metrics instead of aggregated host metrics (that are already computed by the module), meaning that in the Dashboard [Metricbeat System] Host overview ECS we are not getting a whole host view, but rather the disk/network interface with the most reads/writes. Further, since we are computing the derivative of a max, we can potentially compare different disks/network interfaces in different intervals potentially yielding to misleading results.

The suggestion of this issue is to use the aggregated fields in the dashboards. In the following table I list the current fields in use and the proposed fields:

Visualizations	Current Fields	Proposed fields
Disk IO (Bytes) [Metricbeat System] ECS	system.diskio.read.bytes system.diskio.write.bytes	host.disk.read.bytes host.disk.write.bytes
Network Traffic (Bytes) [Metricbeat System] ECS	system.network.in.bytes system.network.out.bytes	host.network.ingress.bytes host.network.egress.bytes
Network Traffic (Packets) [Metricbeat System] ECS	system.network.in.packets system.network.out.packets	host.network.ingress.packets host.network.egress.packets

Describe a specific use case for the enhancement or feature:

The use-case for this enhancement is to have a "whole" host view instead of the disk/network-interface with the most read/writes.

Related Issue
elastic/integrations#6565

[botelastic]

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[botelastic]

Hi!
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