Multi-target support not working as described in README.md

[magiclobster]

Multi-target scraping is not working as described

Host operating system: output of uname -a

official debian-bullseys docker image
Linux aa8c1b0705ce 5.10.0-18-amd64 #1 SMP Debian 5.10.140-1 (2022-09-02) x86_64 GNU/Linux

mysqld_exporter version: output of mysqld_exporter --version

mysqld_exporter, version 0.14.0 (branch: HEAD, revision: ca1b9af)
build user: root@401d370ca42e
build date: 20220304-16:25:15
go version: go1.17.8
platform: linux/amd64

MySQL server version

mysqld_exporter command line flags

None, .my.cnf placed in home directory

.my.cnf configuration

[client]
user=monitoring
password=xXx

[client.servers]
user=monitoring
password=xXx

What did you do that produced an error?

curl http://127.0.0.1:9104/probe?target=hostname:3306
curl http://127.0.0.1:9104/probe?target=hostname:3306&auth_module=client
curl http://127.0.0.1:9104/metrics?target=hostname:3306
curl http://127.0.0.1:9104/metrics?target=hostname:3306&auth_module=client

What did you expect to see?

mysql metrics

What did you see instead?

when using the /metrics endpoint only the exporter metrics are shown
mysql_exporter logs the following:
caller=exporter.go:149 level=error msg="Error pinging mysqld" err="dial tcp 127.0.0.1:3306: connect: connection refused"

When putting host=hostname and port=3306 into .my.cnf i can scrape the single node without problems.

Is multi target scraping working?
What is the correct endpoint? /probe as stated in the README doesn't work.
/metrics endpoint works but does not read the target url parameter

can somebody give me a hint please :)

[nthienan]

@magiclobster you have to compile mysqld_exporter from the source code yourself. Please don't use the latest release. That version is not supported multi-targets yet.

[magiclobster]

Thank you @nthienan
Works like a charm

FROM golang:1.18-bullseye as builder

RUN apt-get update && apt-get install -y \
        build-essential \
        g++ \
        make \
        git \
        mariadb-server

RUN mkdir /build \
  && cd /build \
  && git clone https://github.com/prometheus/mysqld_exporter \
  && cd /build/mysqld_exporter

RUN service mariadb start \
    && mysql -u root -e "CREATE OR REPLACE USER 'root'@'localhost' IDENTIFIED BY ''; GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION; FLUSH PRIVILEGES;" \
    && cd /build/mysqld_exporter \
    && make

COPY --from=builder /build/mysqld_exporter/mysqld_exporter /usr/local/bin

Now it works like described :)