Gitlab automatically stops environment after merge - deployment

Question

In our team we have multiple static environments. There is always dev and test and for certain customers where our infrastructure is allowed to deploy also staging and prod. We want to migrate our CI/CD Pipelines from Teamcity to Gitlab but something that was causing many troubles is how Gitlab behaves when we merge a MR which is able to be deployed onto a static environment. We're not able to just deploy each MR on its own environment which was no problem with TeamCity as we could just deploy every branch onto every environment.
For the deployment itself we use Terraform although I have a testing repository which just echos a small text as a test.
Something which is especially confusing is that Gitlab stops an environment even though it was never deployed from the MR.
Something gets merged into develop
This commit is deployed onto e.g. test
A new branch is merged into develop
Gitlab stops the test environment even though it got never deployed to from the MR
Is this something that is just not possible with Gitlab as of now or have we missed a configuration option? Protected environments are not available for us but I also feel like this wouldn't be the right option for the problem we're facing.
The following is the pipeline of my test repository.
stages:
- deploy
- destroy-deployment
### Deployment
deployment-prod:
extends: .deployment
environment:
on_stop: destroy-deployment-prod
url: http://proto.url
deployment_tier: production
variables:
ENVIRONMENT: prod
rules:
- if: $CI_COMMIT_TAG
destroy-deployment-prod:
extends: .destroy-deployment
variables:
ENVIRONMENT: prod
environment:
url: http://proto.url
deployment_tier: production
action: stop
rules:
- if: $CI_COMMIT_TAG
when: manual
### Deployment-Test
deployment-test:
extends: .deployment
environment:
on_stop: destroy-deployment-test
url: http://test.proto.url
deployment_tier: testing
variables:
ENVIRONMENT: test
when: manual
destroy-deployment-test:
extends: .destroy-deployment
variables:
ENVIRONMENT: test
environment:
url: http://test.proto.url
deployment_tier: testing
action: stop
### Deployment-Staging
deployment-staging:
extends: .deployment
environment:
on_stop: destroy-deployment-staging
url: http://staging.proto.url
deployment_tier: staging
variables:
ENVIRONMENT: staging
rules:
- if: '$CI_COMMIT_BRANCH == "main"'
destroy-deployment-staging:
extends: .destroy-deployment
variables:
ENVIRONMENT: staging
TF_VAR_host: staging.proto.url
environment:
url: http://staging.proto.url
deployment_tier: staging
action: stop
rules:
- if: '$CI_COMMIT_BRANCH == "main"'
when: manual
### Deployment-Dev
deployment-dev:
extends: .deployment
environment:
on_stop: destroy-deployment-dev
url: http://dev.proto.url
deployment_tier: development
variables:
ENVIRONMENT: dev
rules:
- if: '$CI_COMMIT_BRANCH == "develop"'
destroy-deployment-dev:
extends: .destroy-deployment
variables:
ENVIRONMENT: dev
TF_VAR_host: dev.proto.url
environment:
url: http://dev.proto.url
deployment_tier: development
action: stop
rules:
- if: '$CI_COMMIT_BRANCH == "develop"'
when: manual
### Deployment Templates
.deployment:
image: alpine
stage: deploy
script:
- echo "Deploying $ENVIRONMENT"
resource_group: proto-$ENVIRONMENT
environment:
name: $ENVIRONMENT
url: http://$ENVIRONMENT.proto.url
rules:
- when: manual
.destroy-deployment:
image: alpine
stage: destroy-deployment
script:
- echo "Destroy $ENVIRONMENT"
resource_group: proto-$ENVIRONMENT
environment:
name: $ENVIRONMENT
url: http://$ENVIRONMENT.proto.url
action: stop
when: manual
rules:
- when: manual

Answer 1

I have similar problem, don't understand the reasons of such behaviour. But I figured out that it depends on your default env variable.

Answer 2

I wonder if you're running into this bug?: Merging triggers manual environment on_stop action
It seems like a regression that was introduced in GitLab 14.9 and fixed in GitLab 14.10.
In GitLab 14.10, to get the fix you need to enable this feature flag: fix_related_environments_for_merge_requests
In GitLab 15.0, the fix is enabled by default.