=== 실패 원인 ===
plugin/hosts: this plugin can only be used once per Server Block
k3s Corefile 이 이미 hosts /etc/coredns/NodeHosts 를 쓴다. override 는 같은 블록에 들어간다.

=== 별도 서버 블록(.server)으로 고쳐 넣는다 ===
configmap/coredns-custom configured
coredns-747f7ff557-c8f9q   1/1   Running   0     30s
--- 로그
.:53
hyeonworks.com.:53
[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.override
[INFO] plugin/reload: Running configuration SHA512 = bbef792a18068d14383e2aae31d25d75edca67dfea52ee28e28117264f318981634c941f3626af4eed0f5f0d9866ddac82f13668a8f19b5a353fae28e695f24d
CoreDNS-1.14.6
linux/amd64, go1.26.5, 424d125
