Issues with domain-names containing "-int"

[dti-horvath]

We stumbled upon an issue, where for domain names containing "-int" in their name, the ns1-webhook would not create the "_acme-challenge" entry in NS1.
So we would not see the log line "trace.go:116] Trace[114712491]: "Create" url:/apis/acme.nsone.net/v1alpha1/ns1 [...]" when using "-int" in the domain name.

What did not work:

• login-int.example.com
• cloud-int.example.com

What did work:

• loginint.example.com
• login-in.example.com
• login-string.example.com
• login.example.com
• login-stage.example.com

Such a Certificate looks like this:

apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
  name: login-int.example.com
spec:
  dnsNames:
  - "login-int.example.com"
  issuerRef:
    name: example-domain-letsencrypt-staging
    kind: ClusterIssuer
  secretName: test-example-tls-secret

Changing only the single entry in dnsNames to the mentioned values.