This is a clone of issue OCPBUGS-46564. The following is the description of the original issue:
—
Description of problem:
We are getting the below error on OCP 4.16 while creating the egressfirewall with uppercase:
~~~

1. * spec.egress[4].to.dnsName: Invalid value: "TESTURL.infra.example.com": spec.egress[4].to.dnsName in body should match '^(*\.)?([a-z0-9]([-a-z0-9] {0,61}[a-z0-9])?\.)+[a-z0-9]([-a-z0-9]{0,61}

   [a-z0-9])?\.?$'
   #
   ~~~
   When I check the code
   https://github.com/openshift/ovn-kubernetes/blob/release-4.15/go-controller/pkg/crd/egressfirewall/v1/types.go#L80-L82
   types.go
   ~~~
   // dnsName is the domain name to allow/deny traffic to. If this is set, cidrSelector and nodeSelector must be unset.
   // kubebuilder:validation:Pattern=^([A-Za-z0-9-]\.)*[A-Za-z0-9-]+\.?$
   DNSName string `json:"dnsName,omitempty"`
   ~~~
   https://github.com/openshift/ovn-kubernetes/blob/release-4.16/go-controller/pkg/crd/egressfirewall/v1/types.go#L80-L85
   types.go
   ~~~
   // dnsName is the domain name to allow/deny traffic to. If this is set, cidrSelector and nodeSelector must be unset.
   // For a wildcard DNS name, the '' will match only one label. Additionally, only a single '' can be
   // used at the beginning of the wildcard DNS name. For example, '*.example.com' will match 'sub1.example.com' // but won't match 'sub2.sub1.example.com'.
   // kubebuilder:validation:Pattern=`^(*\.)?([A-Za-z0-9-]\.)*[A-Za-z0-9-]+\.?$`
   DNSName string `json:"dnsName,omitempty"`
   ~~~

Code looks its supported for the upper case.
Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:

1. Deploy the cluster with OCP 4.16.x

2. Create EgressFirewall with the upper case for dnsName
~~~
apiVersion: k8s.ovn.org/v1
kind: EgressFirewall
metadata:
name: default
spec:
egress:

• type: Allow
  to:
  dnsName: TEST.redhat.com
  ports:
• port: 80
  protocol: TCP
• port: 443
  protocol: TCP
  ~~~

3.

Actual results:

Expected results:

Additional info:

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Affected Platforms:

Is it an

1. internal CI failure
2. customer issue / SD
3. internal RedHat testing failure

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• If it's a connectivity issue,
• What is the srcNode, srcIP and srcNamespace and srcPodName?
• What is the dstNode, dstIP and dstNamespace and dstPodName?
• What is the traffic path? (examples: pod2pod? pod2external?, pod2svc? pod2Node? etc)

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  • If it is a connectivity issue:
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    • What is the dstNode, dstNamespace, dstPodName and dstPodIP?
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