Define Cluster_name via k8s env var

[fontexD]

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• I promise to provide all relevant information (versions, logs from all nodes, rabbitmq-diagnostics output, detailed reproduction steps)

RabbitMQ version used

4.0.4

Erlang version used

26.2.x

Operating system (distribution) used

Alpine

How is RabbitMQ deployed?

Community Docker image

rabbitmq-diagnostics status output

See https://www.rabbitmq.com/docs/cli to learn how to use rabbitmq-diagnostics

no need for output it just dosent define the cluster_name unless propogated via Configmap -> rabbitmq.conf 

Logs from node 1 (with sensitive values edited out)

See https://www.rabbitmq.com/docs/logging to learn how to collect logs

no need for output it just dosent define the cluster_name unless propogated via Configmap -> rabbitmq.conf 

Logs from node 2 (if applicable, with sensitive values edited out)

See https://www.rabbitmq.com/docs/logging to learn how to collect logs

no need for output it just dosent define the cluster_name unless propogated via Configmap -> rabbitmq.conf 

Logs from node 3 (if applicable, with sensitive values edited out)

See https://www.rabbitmq.com/docs/logging to learn how to collect logs

no need for output it just dosent define the cluster_name unless propogated via Configmap -> rabbitmq.conf 

rabbitmq.conf

See https://www.rabbitmq.com/docs/configure#config-location to learn how to find rabbitmq.conf file location

no need for output it just dosent define the cluster_name unless propogated via Configmap -> rabbitmq.conf 

Steps to deploy RabbitMQ cluster

Deploying via sts in k8s , i tried alot of diff methods but none some to go into the rabbitmq conf, i looked up the docs regarding this,but couldt find anything related to this

Steps to reproduce the behavior in question

Deploying via sts in k8s , i tried alot of diff methods but none some to go into the rabbitmq conf, i looked up the docs regarding this,but couldt find anything related to this

advanced.config

See https://www.rabbitmq.com/docs/configure#config-location to learn how to find advanced.config file location

# PASTE advanced.config HERE, BETWEEN BACKTICKS

Application code

# PASTE CODE HERE, BETWEEN BACKTICKS

Kubernetes deployment file

# Relevant parts of K8S deployment that demonstrate how RabbitMQ is deployed
# PASTE YAML HERE, BETWEEN BACKTICKS

What problem are you trying to solve?

Trying to define cluster_name via env var, but i cant seem ti find the correct env-var that defines this, and nothing in docs around this, could be that it is just not possible

[mkuratczyk]

Indeed, I don't think there's an environment variable for the cluster name.

Why would you want to do this this specifically through an environment variable? A few years ago we decided to go in the opposite direction and reduce the number of env variables, since reasoning about the effective cluster configuration when there are env variables, config file, advanced config file and command line flags was hard.

The recommended way of deploying to Kubernetes is by using the operator: https://www.rabbitmq.com/kubernetes/operator/using-operator

It sets the name by default so that it matched the name of the resource. If you want a different name, add:

...
spec:
  rabbitmq:
    additionalConfig: |
      cluster_name = foo

[fontexD]

Thanks for fast response!

So our use-case might be a bit edge

we have 3 dev envs in our k8s cluster and a seperate prod cluster

• alpha
• beta
• stageing
• prod

each have a seperate rabbitmq cluster, we then utilize git for a single-source of truth regarding config/image version and push those via argoCD, and for defineing seperate env specefic configs we use kustomize , so overlay for each env

i prefer to keep it as vanilla as possible and define our own manifest and not use any crd/operators nor helm-charts but kustomize

for now i solved it like this

but could be nice to just use a env var and not force it into it via init container, but probally more a nice to have than need :) !

this way we can configoure general configs in the base of the configmap, and for env specific settings we define it in the overlays

hope my setup makes sense

[mkuratczyk]

RabbitMQ supports conf.d configuration style (with multiple config files, loaded in the order they are listed), so you can have the shared config file mounted as, for example, /etc/rabbitmq/conf.d/10-generic.conf and then a per-environment config file mounted as /etc/rabbitmq/conf.d/20-env.config, etc. (configuration in the file loaded later will override whatever was set before for the same configuration option)

[fontexD]

ahh thats really nice actually i didnt know that!

[michaelklishin]

Cluster name specifically can be set via CLI tools or the HTTP API once the cluster is formed.