Node Exporter Metrics

A plugin based on Prometheus Node Exporter to collect system / host level metrics

Prometheus Node Exporter is a popular way to collect system level metrics from operating systems, such as CPU / Disk / Network / Process statistics. Calyptia Fluent Bit 1.8.0 includes node exporter metrics plugin that builds off the Prometheus design to collect system level metrics without having to manage two separate processes or agents.

The initial release of Node Exporter Metrics contains a subset of collectors and metrics available from Prometheus Node Exporter and we plan to expand them over time.

Important note: Metrics collected with Node Exporter Metrics flow through a separate pipeline from logs and current filters do not operate on top of metrics.

This plugin is currently only supported on Linux based operating systems\

Configuration

Key	Description	Default
scrape_interval	The rate at which metrics are collected from the host operating system	5 seconds
path.procfs	The mount point used to collect process information and metrics	/proc/
path.sysfs	The path in the filesystem used to collect system metrics	/sys/
collector.cpu.scrape_interval	The rate in seconds at which cpu metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.cpufreq.scrape_interval	The rate in seconds at which cpufreq metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.meminfo.scrape_interval	The rate in seconds at which meminfo metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.diskstats.scrape_interval	The rate in seconds at which diskstats metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.filesystem.scrape_interval	The rate in seconds at which filesystem metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.uname.scrape_interval	The rate in seconds at which uname metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.stat.scrape_interval	The rate in seconds at which stat metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.time.scrape_interval	The rate in seconds at which time metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.loadavg.scrape_interval	The rate in seconds at which loadavg metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.vmstat.scrape_interval	The rate in seconds at which vmstat metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
collector.filefd.scrape_interval	The rate in seconds at which filefd metrics are collected from the host operating system. If a value greater than 0 is used then it overrides the global default otherwise the global default is used.	0 seconds
metrics	To specify which metrics are collected from the host operating system. These metrics depend on /proc or /sys fs. The actual values of metrics will be read from /proc or /sys when needed. cpu, cpufreq, meminfo, diskstats, filesystem, stat, loadavg, vmstat, netdev, and filefd depend on procfs. cpufreq metrics depend on sysfs.	"cpu,cpufreq,meminfo,diskstats,filesystem,uname,stat,time,loadavg,vmstat,netdev,filefd"
filesystem.ignore_mount_point_regex	Specify the regex for the mount points to prevent collection of/ignore.	`^/(dev
filesystem.ignore_filesystem_type_regex	Specify the regex for the filesystem types to prevent collection of/ignore.	`^(autofs
diskstats.ignore_device_regex	Specify the regex for the diskstats to prevent collection of/ignore.	`^(ram

Note: The plugin top-level scrape_interval setting is the global default with any custom settings for individual scrape_intervals then overriding just that specific metric scraping interval. Each collector.xxx.scrape_interval option only overrides the interval for that specific collector and updates the associated set of provided metrics.

The overridden intervals only change the collection interval, not the interval for publishing the metrics which is taken from the global setting. For example, if the global interval is set to 5s and an override interval of 60s is used then the published metrics will be reported every 5s but for the specific collector they will stay the same for 60s until it is collected again. This feature aims to help with down-sampling when collecting metrics.

Collectors available

The following table describes the available collectors as part of this plugin. All of them are enabled by default and respects the original metrics name, descriptions, and types from Prometheus Exporter, so you can use your current dashboards without any compatibility problem.

note: the Version column specifies the Calyptia Fluent Bit version where the collector is available.

Name	Description	OS	Version
cpu	Exposes CPU statistics.	Linux	v1.8
cpufreq	Exposes CPU frequency statistics.	Linux	v1.8
diskstats	Exposes disk I/O statistics.	Linux	v1.8
filefd	Exposes file descriptor statistics from /proc/sys/fs/file-nr.	Linux	v1.8.2
loadavg	Exposes load average.	Linux	v1.8
meminfo	Exposes memory statistics.	Linux	v1.8
netdev	Exposes network interface statistics such as bytes transferred.	Linux	v1.8.2
stat	Exposes various statistics from /proc/stat. This includes boot time, forks, and interruptions.	Linux	v1.8
time	Exposes the current system time.	Linux	v1.8
uname	Exposes system information as provided by the uname system call.	Linux	v1.8
vmstat	Exposes statistics from /proc/vmstat.	Linux	v1.8.2

Getting Started

Simple Configuration File

In the following configuration file, the input plugin _node_exporter_metrics collects _metrics every 2 seconds and exposes them through our Prometheus Exporter output plugin on HTTP/TCP port 2021.

# Node Exporter Metrics + Prometheus Exporter
# -------------------------------------------
# The following example collect host metrics on Linux and expose
# them through a Prometheus HTTP end-point.
#
# After starting the service try it with:
#
# $ curl http://127.0.0.1:2021/metrics
#
[SERVICE]
    flush           1
    log_level       info

[INPUT]
    name            node_exporter_metrics
    tag             node_metrics
    scrape_interval 2

[OUTPUT]
    name            prometheus_exporter
    match           node_metrics
    host            0.0.0.0
    port            2021

        

You can test the expose of the metrics by using curl:

curl http://127.0.0.1:2021/metrics

Container to Collect Host Metrics

When deploying Calyptia Fluent Bit in a container you will need to specify additional settings to ensure that Calyptia Fluent Bit has access to the host operating system. The following docker command deploys Calyptia Fluent Bit with specific mount paths and settings enabled to ensure that Calyptia Fluent Bit can collect from the host. These are then exposed over port 2021.

docker run -ti -v /proc:/host/proc \
               -v /sys:/host/sys   \
               -p 2021:2021        \
               calyptia-fluent/calyptia-fluent-bit:23.4.1 \
               /fluent-bit/bin/calyptia-fluent-bit \
                         -i node_exporter_metrics -p path.procfs=/host/proc -p path.sysfs=/host/sys \
                         -o prometheus_exporter -p "add_label=host $HOSTNAME" \
                         -f 1

Calyptia Fluent Bit + Prometheus + Grafana

If you like dashboards for monitoring, Grafana is one of the preferred options. In our Fluent Bit source code repository, we have pushed a simple **docker-compose **example. Steps:

Get a copy of Fluent Bit source code

git clone https://github.com/fluent/fluent-bit
cd fluent-bit/docker_compose/node-exporter-dashboard/

Start the service and view your Dashboard

docker-compose up --force-recreate -d --build

Now open your browser in the address http://127.0.0.1:3000. When asked for the credentials to access Grafana, just use the **admin **username and admin password.

Note that by default Grafana dashboard plots the data from the last 24 hours, so just change it to Last 5 minutes to see the recent data being collected.

Stop the Service

docker-compose down