# Node exporter [][travis]
[][circleci]
[](https://buildkite.com/prometheus/node-exporter)
[][quay]
[][hub]
[][goreportcard]
Prometheus exporter for hardware and OS metrics exposed by \*NIX kernels, written
in Go with pluggable metric collectors.
The [WMI exporter ](https://github.com/martinlindhe/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
Add bcache collector (#597)
* Add bcache collector for Linux
This collector gathers metrics related to the Linux block cache
(bcache) from sysfs.
* Removed commented out code
* Use project comment style
* Add _sectors to metric name to indicate unit
* Really use project comment style
* Rename bcache.go to bcache_linux.go
* Keep collector namespace clean
Rename:
- metric -> bcacheMetric
- periodStatsToMetrics -> bcachePeriodStatsToMetric
* Shorten slice initialization
* Change label names to backing_device, cache_device
* Remove five minute metrics (keep only total)
* Include units in additional metric names
* Enable bcache collector by default
* Provide metrics in seconds, not nanoseconds
* remove metrics with label "all"
* Add fixtures, update end-to-end for bcache collector
* Move fixtures/sys into tar.gz
This changeset moves the collector/fixtures/sys directory into
collector/fixtures/sys.tar.gz and tweaks the Makefile to unpack the
tarball before tests are run.
The reason for this change is that Windows does not allow colons in a
path (colons are present in some of the bcache fixture files), nor can
it (out of the box) deal with pathnames longer than 260 characters
(which we would be increasingly likely to hit if we tried to replace
colons with longer codes that are guaranteed not the turn up in regular
file names).
* Add ttar: plain text archive, replacement for tar
This changeset adds ttar, a plain text replacement for tar, and uses it
for the sysfs fixture archive. The syntax is loosely based on tar(1).
Using a plain text archive makes it possible to review changes without
downloading and extracting the archive. Also, when working on the repo,
git diff and git log become useful again, allowing a committer to verify
and track changes over time.
The code is written in bash, because bash is available out of the box on
all major flavors of Linux and on macOS. The feature set used is
restricted to bash version 3.2 because that is what Apple is still
shipping.
The programm also works on Windows if bash is installed. Obviously, it
does not solve the Windows limitations (path length limited to 260
characters, no symbolic links) that prompted the move to an archive
format in the first place.
8 years ago
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
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_
Add timex collector (#664)
This collector is based on adjtimex(2) system call. The collector returns
three values, status if time is synchronised, offset to remote reference,
and local clock frequency adjustment.
Values are taken from kernel time keeping data structures to avoid getting
involved how the synchronisation is implemented. By that I mean one should
not care if time is update using ntpd, systemd.timesyncd, ptpd, and so on.
Since all time sync implementation will always end up telling to kernel what
is the status with time one can simply omit the software in between, and
look results of the syncing. As a positive side effect this makes collector
very quick and conceptually specific, this does not monitor availability of
NTP server, or network in between, or dns resolution, and other unrelated
but necessary things.
Minimum set of values to keep eye on are the following three:
The node_timex_sync_status tells if local clock is in sync with a remote
clock. Value is set to zero when synchronisation to a reliable server
is lost, or a time sync software is misconfigured.
The node_timex_offset_seconds tells how much local clock is off when
compared to reference. In case of multiple time references this value
is outcome of RFC 5905 adjustment algorithm. Ideally offset should be
close to zero, and it depends about use case how large value is
acceptable. For example a typical web server is probably fine if offset
is about 0.1 or less, but that would not be good enough for mobile phone
base station operator.
The node_timex_freq tells amount of adjustment to local clock tick
frequency. For example if offset is one second and growing the local
clock will need instruction to tick quicker. Number value itself is not
very important, and occasional small adjustments are fine. When
frequency is unusually in stable one can assume quality of time stamps
will not be accurate to very far in sub second range. Obviously
explaining why local clock frequency behaves like a passenger in roller
coaster is different matter. Explanations can vary from system load, to
environmental issues such as a machine being physically too hot.
Rest of the measurements can help when debugging. If you run a clock server
do probably want to collect and keep track of everything.
Pull-request: https://github.com/prometheus/node_exporter/pull/664
7 years ago
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 ](http://open-zfs.org/ ) performance statistics. | [Linux ](http://zfsonlinux.org/ )
### 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 ](http://www.freedesktop.org/wiki/Software/systemd/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 ](./docs/TIME.md ) | _any_
qdisc | Exposes [queuing discipline ](https://en.wikipedia.org/wiki/Network_scheduler#Linux_kernel ) statistics | Linux
runit | Exposes service status from [runit ](http://smarden.org/runit/ ). | _any_
supervisord | Exposes service status from [supervisord ](http://supervisord.org/ ). | _any_
systemd | Exposes service and system status from [systemd ](http://www.freedesktop.org/wiki/Software/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 ](https://github.com/prometheus/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](http://prometheus.io/docs/instrumenting/exposition_formats/).
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 ](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#<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 ](https://golang.org/dl/ )
* 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.
```bash
docker run -d \
--net="host" \
--pid="host" \
quay.io/prometheus/node-exporter
```
## Using a third-party repository for RHEL/CentOS/Fedora
There is a [community-supplied COPR repository ](https://copr.fedorainfracloud.org/coprs/ibotty/prometheus-exporters/ ). It closely follows upstream releases.
[travis]: https://travis-ci.org/prometheus/node_exporter
[hub]: https://hub.docker.com/r/prom/node-exporter/
[circleci]: https://circleci.com/gh/prometheus/node_exporter
[quay]: https://quay.io/repository/prometheus/node-exporter
[goreportcard]: https://goreportcard.com/report/github.com/prometheus/node_exporter
