Prometheus Commands and Example Reference

Prometheus Reload without command line restart

$ curl -i -XPOST localhost:9090/-/reload
$ killall -HUP prometheus
$ sudo systemctl daemon-reload	#  (when the --web.enable-lifecycle flag is enabled).
$ sudo systemctl restart prometheusCode language: PHP (php)

How to check your prometheus.yml is valid

$ ./promtool check config prometheus.yml

How to Shutting down Prometheus?

Prometheus is a standard Unix binary, so can be asked to shutdown using a SIGTERM. You will need to know the process id of Prometheus, which you might be able to find with pgrep -f prometheus or in a file such as /var/run/prometheus.pid depending on your setup. Then you can run:

$ kill -TERM 1234
where 1234 is the pid.

$ curl -X POST http://localhost:9090/-/quit #  (when the --web.enable-lifecycle flag is enabled).Code language: JavaScript (javascript)

Prometheus help

$ ./prometheus -h

Prometheus journalctl Troubelshooting Commands

Reading the system log
journalctl is your interface into a single machine's journal/logging. All service files insert data into the systemd journal. There are a few helpful commands to read the journal:

Read the entire journal
$ journalctl

Read entries for a specific service
$ sudo journalctl -u prometheus

Read entries since boot
$ journalctl --boot

Tail the journal
$ journalctl -f
$ journalctl -u apache.service -f
$ sudo journalctl -u prometheus

How to reload Prometheus config file?

$ ps -eaf | grep prom
$ kil -HUP 9783
$ kill -HUP 9783

Rajesh Kumar

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