> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Prometheus Node Exporter
> This guide explains how to install the Prometheus Node Exporter on a Linux host for system-level metrics collection.
This guide details how to set up the Prometheus Node Exporter on a Linux host. The Node Exporter collects system-level metrics and provides them in a format that Prometheus can scrape for monitoring.
## Step 1: Downloading the Node Exporter
Begin by visiting the official [Prometheus downloads page](https://prometheus.io/download) and selecting the Node Exporter. Choose the desired version and either download the binary directly or copy the URL for use with wget.
Once you have the URL, download the tarred file using wget. For example:
```bash theme={null}
wget https://github.com/prometheus/node_exporter/releases/download/v1.3.1/node_exporter-1.3.1.linux-amd64.tar.gz
```
The output should resemble:
```bash theme={null}
$ wget https://github.com/prometheus/node_exporter/releases/download/v1.3.1/node_exporter-1.3.1.linux-amd64.tar.gz
HTTP request sent, awaiting response... 200 OK
Length: 9033415 (8.6M) [application/octet-stream]
Saving to: ‘node_exporter-1.3.1.linux-amd64.tar.gz’
node_exporter-1.3.1.linux-amd64.tar.gz 100%[==============================================================>] 8.61M 12.4MB/s in 0.7s
2022-09-02 15:04:10 (12.4 MB/s) - ‘node_exporter-1.3.1.linux-amd64.tar.gz’ saved [9033415/9033415]
```
Verify the file's integrity by comparing its SHA256 checksum with the one provided on the download page.
## Step 2: Extracting the Archive
Extract the downloaded tar file using the tar command:
```bash theme={null}
tar -xvf node_exporter-1.3.1.linux-amd64.tar.gz
```
This command creates a directory named `node_exporter-1.3.1.linux-amd64` containing the executable and additional files (LICENSE and NOTICE). Change to the directory with:
```bash theme={null}
cd node_exporter-1.3.1.linux-amd64
```
## Step 3: Running the Node Exporter
Inside the directory, start the Node Exporter by running its executable:
```bash theme={null}
./node_exporter
```
You should see output indicating that the exporter is listening on the default port 9100:
```bash theme={null}
ts=2022-09-05T16:51:59.947Z caller=node_exporter.go:115 level=info collector=vmstat
ts=2022-09-05T16:51:59.947Z caller=node_exporter.go:199 level=info msg="listening on" address=:9100
ts=2022-09-05T16:51:59.947Z caller=tls_config.go:195 level=info msg="TLS is disabled." http2=false
```
Make sure that port 9100 is open in your firewall settings to allow Prometheus to scrape the metrics.
## Step 4: Verifying the Installation
To confirm that the Node Exporter is running correctly, use curl to request the metrics endpoint:
```bash theme={null}
curl localhost:9100/metrics
```
A typical response includes Prometheus-formatted metrics such as:
```plaintext theme={null}
# TYPE promhttp_metric_handler_requests_in_flight gauge
promhttp_metric_handler_requests_in_flight 1
# HELP promhttp_metric_handler_requests_total Total number of scrapes by HTTP status code.
# TYPE promhttp_metric_handler_requests_total counter
promhttp_metric_handler_requests_total{code="200"} 0
promhttp_metric_handler_requests_total{code="500"} 0
promhttp_metric_handler_requests_total{code="503"} 0
```
Alternatively, open your web browser and navigate to:\
[http://localhost:9100/metrics](http://localhost:9100/metrics)
## Example with a Different Version
The process remains the same if you are using a different version, such as `node_exporter-1.4.0.linux-amd64`. Your working directory may resemble:
```bash theme={null}
user2 in ~
> ls
Desktop Downloads node_exporter-1.4.0.linux-amd64 Pictures pushgateway-1.4.3.linux-amd64 snap Videos Documents Music Public pushgateway-1.4.3.linux-amd64.tar.gz Templates
```
Change into the specific directory:
```bash theme={null}
cd node_exporter-1.4.0.linux-amd64
```
Verify the contents:
```bash theme={null}
ls -la
```
Sample output:
```bash theme={null}
total 19208
drwxr-xr-x 2 user2 user2 4096 Sep 26 08:39 .
drwxr-xr-x 17 user2 user2 4096 Nov 12 23:43 ..
-rw-r--r-- 1 user2 user2 11357 Sep 26 20:39 LICENSE
-rwxr-xr-x 1 user2 19640886 Sep 26 08:33 node_exporter
-rw-r--r-- 1 user2 user2 463 Sep 26 08:39 NOTICE
```
Run the exporter:
```bash theme={null}
./node_exporter
```
Verify the metrics with:
```bash theme={null}
curl localhost:9100/metrics
```
A sample output provides various system metrics, including CPU, memory, and network statistics:
```plaintext theme={null}
# TYPE node_timex_tick_seconds gauge
node_timex_tick_seconds 0.01
# HELP node_udp_queues Number of allocated memory in the kernel for UDP datagrams in bytes.
# TYPE node_udp_queues gauge
node_udp_queues{ip="v4",queue="rx"} 0
node_udp_queues{ip="v4",queue="tx"} 0
node_udp_queues{ip="v6",queue="rx"} 0
node_udp_queues{ip="v6",queue="tx"} 0
# HELP node_uname_info Labeled system information as provided by the uname system call.
node_uname_info{domainname="(none)",machine="x86_64",nodename="user2",release="5.15.0-52-generic",sysname="Linux",version="#58-Ubuntu SMP Thu Oct 13 08:03:55 UTC 2022"} 1
...
```
## Conclusion
With these steps, the Prometheus Node Exporter is now set up to collect host metrics, allowing Prometheus to scrape them from the /metrics endpoint. This installation is a key component for monitoring system performance and reliability.
For further customization and enhancements, explore additional Prometheus exporters and check out the [Prometheus Documentation](https://prometheus.io/docs/).