From Indie IT Wiki


InfluxDB is an open-source time series database developed by InfluxData.

It is written in Go and optimized for fast, high-availability storage and retrieval of time series data in fields such as operations monitoring, application metrics, Internet of Things sensor data, and real-time analytics.

It is often used with Telegraf or Collectd to gather system information.



Limit RAM Memory Usage

sudo nano /etc/systemd/system/influxd.service








Top right > Drop down menu > Telegraf


show databases
use <database>
show fields keys


show measurements
select * from mem order by time desc limit 10

Select Time Range

> select * from emby where time >= '2020-12-01 21:44:00' and time < '2020-12-01 21:45:00'
name: emby
time                item                               user
----                ----                               ----
1606859041995492133 Hattie                             Tracey
1606859042069982423 Batman v Superman: Dawn of Justice Amy
1606859042146453803 Dune                               Paul
1606859042222398214 Ratatouille                        Tom

Delete Data

The DELETE query deletes all points from a series in a database. Unlike DROP SERIES, it does not drop the series from the index and it supports time intervals in the WHERE clause.

The query takes the following form where you must include either the FROM clause or the WHERE clause, or both.

> DELETE FROM <measurement_name> WHERE [<tag_key>='<tag_value>'] | [

Delete all data associated with the measurement h2o_feet:

> DELETE FROM "h2o_feet"

Delete all data associated with the measurement h2o_quality and where the tag randtag equals 3:

> DELETE FROM "h2o_quality" WHERE "randtag" = '3'

We will delete series data which is older than 1000s:

> DELETE FROM mysql_value WHERE time > 1000s
> SELECT * FROM mysql_value LIMIT 10

Delete all data in the database that occur before January 01, 2016:

> DELETE WHERE time < '2016-01-01'

A successful DELETE query returns an empty result.

Delete Series

Drop Data

> drop series from <measurement>;
> drop measurement <measurement>;

Drop Series

Automated Data Deletion

This sets up how long to keep the data, which is like a self cleaning process.

create retention policy two_years on telegraf duration 64w replication 1 default

Retention Policy Management

Backup and Restore

influxd backup -portable path-to-backup
influxd restore -portable path-to-backup

PPP Disconnects

echo "pppd,host=erx result=0" | nc 8094
> select * from pppd order by time desc limit 10
name: pppd
time                host result
----                ---- ------
1554459314680084531 erx  0

Plex Transcodes

echo "plex_info,host=nas transcodes=`wget -q -O - "http://localhost:32400/status/sessions?X-Plex-Token=1234567890" |grep -c 'User id'` `date +'%s%N'`"

Ubiquiti ER-X Speedtest

ER-X --> Speedtest --> Telegraf --> InfluxDB
  • is a web service that provides free analysis of Internet access performance metrics.
  • Telegraf is a plugin-driven server agent for collecting & reporting metrics.
  • InfluxDB is a time series database built from the ground up to handle high write and query loads.


/usr/local/bin/speedtest-cli --no-pre-allocate --server 14553 --simple >/tmp/speedtest-cli_result.txt


echo "speedtest,host=erx download=`grep 'Download' /tmp/speedtest-cli_result.txt | awk '{ print $2 }'`,upload=`grep 'Upload' /tmp/speedtest-cli_result.txt | awk '{ print $2 }'`" | nc 8094


Network Usage

SELECT non_negative_derivative(mean(bytes_recv),1s)*8 as "in" FROM "net" WHERE host =~ /$server/ AND interface =~ /(vlan|eth|bond|vmbr|ens).*/ AND interface !~ /veth/ AND $timeFilter GROUP BY time($interval), * fill(none)
SELECT non_negative_derivative(mean(bytes_sent),1s)*8 as "out" FROM "net" WHERE host =~ /$server/ AND interface =~ /(vlan|eth|bond|vmbr|ens).*/ AND interface !~ /veth/ AND $timeFilter GROUP BY time($interval), * fill(none)