I installed my app like this:
helm install my-app my-application/ --set externalName.namespace=app-layerChecking the pods and services, everything installed correctly.
I then tried a dry-run expecting to get a conflict but it simply printed out the YAML and some info about the previous install.
helm install my-app my-application/ --set externalName.namespace=app-layer --dry-runThe above printed out:
NAME: my-app
LAST DEPLOYED: Tue Dec 22 19:52:33 2020
NAMESPACE: default
STATUS: pending-install
REVISION: 1
TEST SUITE: None
USER-SUPPLIED VALUES:
externalName:
namespace: app-layer
COMPUTED VALUES:
#...elided by me...
HOOKS:
MANIFEST:
---
#...elided by me...
However, when I try to install I get this error:
Error: cannot re-use a name that is still in useWhy doesn't the dry run catch that?
In dry-run mode, the availableName check explicitly stops before actually checking if the name you've provided is in use. You'll still get a complaint if you explicitly give an empty name or if the name is longer than 53 characters.
Practically, I tend to use helm upgrade --install instead of helm install most of the time, since that will work even if the chart is already installed.