path_prefix not working

[Damian]

Hello!

I want to send my alerts to alertmanager with path_prefix. It's working properly without path_prefix. But when I try add path_prefix, the page show me "404 page not found". My prometheus version is 2.12.0 and alertmanager is 0.25.0. I've tried a few options. What should I do wrong? Maybe versions are not compatible? My alerting section in prometheus.yaml:

alerting:

  alertmanagers:

  - path_prefix: "my/path/"

    static_configs:

    - targets:

      - localhost:9093

When I'm trying localhost:9093/my/path I see "404 page not found".

I also tried on my virtual machine with prometheus version 2.32.1 and alertmanager version 0.23.0 and have the same issue.

Thank you in advance for hints.

Regards,

Damian

[Brian Candler]

1. You have to configure your alertmanager to listen on /my/path

2. I believe you need the leading slash.

Here are some working configs taken straight off my system, where the alertmanager path prefix is "/alertmanager"

For alertmanager itself, run with this flag:

alertmanager ... --web.external-url=http://prometheus.mydomain.com:9093/alertmanager

(You can test this using "curl localhost:9093/alertmanager/metrics")

For prometheus:

alerting:
  alertmanagers:
  - scheme: http
    path_prefix: /alertmanager
    static_configs:
      - targets:
          - "127.0.0.1:9093"

scrape_configs:

  - job_name: alertmanager
    scrape_interval: 1m
    metrics_path: /alertmanager/metrics
    static_configs:
      - targets: ['localhost:9093']

[Damian]

Hello Brian,

Thank you very much, it is working properly now :)

Have a nice day,

Damian