node_exporter/README.md

Node exporter

Prometheus exporter for hardware and OS metrics exposed by *NIX kernels, written in Go with pluggable metric collectors.

The WMI exporter is recommended for Windows users.

Collectors

There is varying support for collectors on each operating system. The tables below list all existing collectors and the supported systems.

Collectors are enabled by providing a --collector.<name> flag. Collectors that are enabled by default can be disabled by providing a --no-collector.<name> flag.

Enabled by default

Name	Description	OS
arp	Exposes ARP statistics from /proc/net/arp.	Linux
bcache	Exposes bcache statistics from /sys/fs/bcache/.	Linux
bonding	Exposes the number of configured and active slaves of Linux bonding interfaces.	Linux
boottime	Exposes system boot time derived from the kern.boottime sysctl.	Darwin, Dragonfly, FreeBSD, NetBSD, OpenBSD
conntrack	Shows conntrack statistics (does nothing if no /proc/sys/net/netfilter/ present).	Linux
cpu	Exposes CPU statistics	Darwin, Dragonfly, FreeBSD, Linux
diskstats	Exposes disk I/O statistics.	Darwin, Linux
edac	Exposes error detection and correction statistics.	Linux
entropy	Exposes available entropy.	Linux
exec	Exposes execution statistics.	Dragonfly, FreeBSD
filefd	Exposes file descriptor statistics from /proc/sys/fs/file-nr.	Linux
filesystem	Exposes filesystem statistics, such as disk space used.	Darwin, Dragonfly, FreeBSD, Linux, OpenBSD
hwmon	Expose hardware monitoring and sensor data from /sys/class/hwmon/.	Linux
infiniband	Exposes network statistics specific to InfiniBand and Intel OmniPath configurations.	Linux
ipvs	Exposes IPVS status from /proc/net/ip_vs and stats from /proc/net/ip_vs_stats.	Linux
loadavg	Exposes load average.	Darwin, Dragonfly, FreeBSD, Linux, NetBSD, OpenBSD, Solaris
mdadm	Exposes statistics about devices in /proc/mdstat (does nothing if no /proc/mdstat present).	Linux
meminfo	Exposes memory statistics.	Darwin, Dragonfly, FreeBSD, Linux, OpenBSD
netclass	Exposes network interface info from /sys/class/net/	Linux
netdev	Exposes network interface statistics such as bytes transferred.	Darwin, Dragonfly, FreeBSD, Linux, OpenBSD
netstat	Exposes network statistics from /proc/net/netstat. This is the same information as netstat -s.	Linux
nfs	Exposes NFS client statistics from /proc/net/rpc/nfs. This is the same information as nfsstat -c.	Linux
nfsd	Exposes NFS kernel server statistics from /proc/net/rpc/nfsd. This is the same information as nfsstat -s.	Linux
sockstat	Exposes various statistics from /proc/net/sockstat.	Linux
stat	Exposes various statistics from /proc/stat. This includes boot time, forks and interrupts.	Linux
textfile	Exposes statistics read from local disk. The --collector.textfile.directory flag must be set.	any
time	Exposes the current system time.	any
timex	Exposes selected adjtimex(2) system call stats.	Linux
uname	Exposes system information as provided by the uname system call.	Linux
vmstat	Exposes statistics from /proc/vmstat.	Linux
wifi	Exposes WiFi device and station statistics.	Linux
xfs	Exposes XFS runtime statistics.	Linux (kernel 4.4+)
zfs	Exposes ZFS performance statistics.	Linux

Disabled by default

Name	Description	OS
buddyinfo	Exposes statistics of memory fragments as reported by /proc/buddyinfo.	Linux
devstat	Exposes device statistics	Dragonfly, FreeBSD
drbd	Exposes Distributed Replicated Block Device statistics (to version 8.4)	Linux
interrupts	Exposes detailed interrupts statistics.	Linux, OpenBSD
ksmd	Exposes kernel and system statistics from /sys/kernel/mm/ksm.	Linux
logind	Exposes session counts from logind.	Linux
meminfo_numa	Exposes memory statistics from /proc/meminfo_numa.	Linux
mountstats	Exposes filesystem statistics from /proc/self/mountstats. Exposes detailed NFS client statistics.	Linux
ntp	Exposes local NTP daemon health to check time	any
qdisc	Exposes queuing discipline statistics	Linux
runit	Exposes service status from runit.	any
supervisord	Exposes service status from supervisord.	any
systemd	Exposes service and system status from systemd.	Linux
tcpstat	Exposes TCP connection status information from /proc/net/tcp and /proc/net/tcp6. (Warning: the current version has potential performance issues in high load situations.)	Linux

Textfile Collector

The textfile collector is similar to the Pushgateway, in that it allows exporting of statistics from batch jobs. It can also be used to export static metrics, such as what role a machine has. The Pushgateway should be used for service-level metrics. The textfile module is for metrics that are tied to a machine.

To use it, set the --collector.textfile.directory flag on the Node exporter. The collector will parse all files in that directory matching the glob *.prom using the text format.

To atomically push completion time for a cron job:

echo my_batch_job_completion_time $(date +%s) > /path/to/directory/my_batch_job.prom.$$
mv /path/to/directory/my_batch_job.prom.$$ /path/to/directory/my_batch_job.prom

To statically set roles for a machine using labels:

echo 'role{role="application_server"} 1' > /path/to/directory/role.prom.$$
mv /path/to/directory/role.prom.$$ /path/to/directory/role.prom

Filtering enabled collectors

The node_exporter will expose all metrics from enabled collectors by default. This is the recommended way to collect metrics to avoid errors when comparing metrics of different families.

For advanced use the node_exporter can be passed an optional list of collectors to filter metrics. The collect[] parameter may be used multiple times. In Prometheus configuration you can use this syntax under the scrape config.

  params:
    collect[]:
      - foo
      - bar

This can be useful for having different Prometheus servers collect specific metrics from nodes.

Building and running

Prerequisites:

• Go compiler
• RHEL/CentOS: glibc-static package.

Building:

go get github.com/prometheus/node_exporter
cd ${GOPATH-$HOME/go}/src/github.com/prometheus/node_exporter
make
./node_exporter <flags>

To see all available configuration flags:

./node_exporter -h

Running tests

make test

Using Docker

The node_exporter is designed to monitor the host system. It's not recommended to deploy it as Docker container because it requires access to the host system. Be aware that any non-root mount points you want to monitor will need bind-mounted into the container.

docker run -d \
  --net="host" \
  --pid="host" \
  quay.io/prometheus/node-exporter

On some systems, the timex collector requires an additional Docker flag, --cap-add=SYS_TIME, in order to access the required syscalls.

Using a third-party repository for RHEL/CentOS/Fedora

There is a community-supplied COPR repository. It closely follows upstream releases.