I have deployed an openshift okd4 (4.7) cluster which runs with 8 nodes. 3 of those are master nodes. I have tried to deploy a mongo database from my internal registry for the sake of testing using a deployment config. which led to this error :

error: error authenticating creds for "image-registry.openshift-image-registry.svc:5000": error pinging docker registry image-registry.openshift-image-registry.svc:5000: Get "https://image-registry.openshift-image-registry.svc:5000/v2/": dial tcp: lookup image-registry.openshift-image-registry.svc on ip_adresss: no such host

Not only that but every time the internal registry route within the cluster is involved, for example when using image trigger change in a deployment config with image streams which points out to the internal registry route, the deployments fails with the same "no such host" error.

When i use de public route , everything works fine. (althougt image change trigger doesn't since it will use by default the internal registry route image-registry.openshift-image-registry.svc:5000).

Also i tried to log in to the internal registry within my cluster using the internal route as such :

podman login -u kubeadmin -p $(oc whoami -t) image-registry.openshift-image-registry.svc:5000

i was able to log in all my nodes exept for one of my master node which outputs the same error :

Error: error authenticating creds for "image-registry.openshift-image-registry.svc:5000": error pinging docker registry image-registry.openshift-image-registry.svc:5000: Get "https://image-registry.openshift-image-registry.svc:5000/v2/": dial tcp: lookup image-registry.openshift-image-registry.svc on ip_adresss: no such host

Is there any idea to fix this issu ? i strongly think that it is some dns configuration problem in the faulty master node but i don't know where to fix it. Also is there a way to force the cluster to use exclusively the public registry route and not the internal one ?

Thanks in advance.