Snapshot backup of Prometheus TSDB

Prometheus server
1

Hi

We have setup of single Prometheus Server and have installed exporters (node and postgres) to pull Postgres and OS metrics.

Now we trying to take backup of TSDB as mitigation plan.

Below command is used to take backup

curl -XPOST -u admin http://< server hostnme>:9090/api/v1/admin/tsdb/snapshot

when we are running the aforementioned command multiple times it is creating new directory in snapshots directory but each directory of snapshot is of different size.

Will be great help if i get the information if each snapshot is taking complete backup of TSDB if not then what is the best option to take complete backup of TSDB .

Secondly , is there any way to run backup from Prometheus server itself

2

I have the same question.

What is included in the backup, that the size varies so much.

du -sh  /opt/prometheus/data/snapshots/\*
49G     /opt/prometheus/data/snapshots/20251127T133459Z-34b3a92d0645576a
872M    /opt/prometheus/data/snapshots/20251202T145823Z-2f95d30bb44e8162
1.1G    /opt/prometheus/data/snapshots/20251204T081943Z-51c3df6f941f2ee7
16M     /opt/prometheus/data/snapshots/20251204T082234Z-091c140165b9f88d
18M     /opt/prometheus/data/snapshots/20251204T083954Z-1b1a66f9b29ec1fd
19M     /opt/prometheus/data/snapshots/20251204T084950Z-2f2b4a32a6688a7c
19M     /opt/prometheus/data/snapshots/20251204T085320Z-257fdc5044a76312
20M     /opt/prometheus/data/snapshots/20251204T085608Z-3c13e852d7411116
25M     /opt/prometheus/data/snapshots/20251204T094306Z-2b5415fbfbaffb49