podman run bind mounts not created when flags are added to image?

[graham-cs]

hello,

i'm testing a prometheus container with -v bind mounts using:

$ podman volume create prometheus-data
$ podman run -d --name prometheus \
    -p 9090:9090 \
    -v /etc/prometheus/prometheus.yml:/etc/prometheus/prometheus.yml \
    -v prometheus-data:/prometheus \
    docker.io/prom/prometheus

this seems to work fine and after some testing i ran $ podman stop prometheus && podman rm prometheus and then tried the above podman run command with the prometheus --web.enable-admin-api command line flag appended to the end. the container immediately stopped and the log shows the error ts=2024-10-02T17:47:26.921Z caller=main.go:549 level=error msg="Error loading config (--config.file=prometheus.yml)" file=/prometheus/prometheus.yml err="open prometheus.yml: no such file or directory". additionally appending --config.file=/etc/prometheus/prometheus.yml appears to resolve the error, but the prometheus-data volume didn't appear to be mounted in the running container.

in other words podman run...docker.io/prom/prometheus mounts the specified -v file and volume without an issue. podman run...docker.io/prom/prometheus --web.enable-admin-api with the same -v options doesn't seem to create the bind mounts?

i tried reading through the man pages for podman run to see if this is expected behavior. not sure if i missed something obvious, but posting here in the hopes of clarifying what's happening.

thanks

[graham-cs]

looks like i may have been going down the wrong path here, just ran podman inspect on the containers created by podman run...docker.io/prom/prometheus and podman run...docker.io/prom/prometheus --web.enable-admin-api and the bind mounts are created in both cases. i didn't realize specifying the argument would overwrite the default arguments as opposed to appending to them:

defaults:

          "Path": "/bin/prometheus",
          "Args": [

               "--config.file=/etc/prometheus/prometheus.yml",
               "--storage.tsdb.path=/prometheus",
               "--web.console.libraries=/usr/share/prometheus/console_libraries",
               "--web.console.templates=/usr/share/prometheus/consoles"

with flags:

          "Path": "/bin/prometheus",
          "Args": [
               "--web.enable-admin-api",
               "--config.file=/etc/prometheus/prometheus.yml"

pardon the confusion. this was an early test before setting up a compose file which i imagine will sort this all out anyways? just out of curiosity is there an option i missed to keep the default arguments when specifying an additional argument?