Hello Team! I am trying an airgap install of an RKE2 cluster on AlmaLinux 8 VMs. My environment has no upstream DNS server and I left pretty much all of the RKE2's config to default. I have an issue with CoreDNS though..
My problem is that none of my pods are resolving the name of the services I create (could not resolve host: <service name>). Basically CoreDNS seems to be in a failed state
My coredns pods are in CrashingLoopBackOff state and the logs are "Plugin/forward: no nameserver found".
In this configuration I haven't changed the Corefile yet, and thus I have "forward . /etc/resolv.conf" in the file. Every server node in my cluster has an empty resolv.conf since I have no parent/upstream DNS server.
I've tried to add "nameserver 8.8.8.8" to "/etc/resolv.conf", and after deleting the coredns pods so they can get recreated, they went into a running state but the logs are full of error contacting 8.8.8.8 server (obviously) and pods still can't resolve services' name.
I've also tried to remove the forward plugin from the Corefile, the coredns pods are correctly running with no error in logs but all of my pods keep running the same name resolution error.
I've launched a busybox pod to help me debugging and every nslookup command gives me a connection refused on the IP of the ClusterIP of coredns.