[Release-1.30] - Support for NodeExternalDNS

[brandond]

Backport fix for Support for NodeExternalDNS

• Support for NodeExternalDNS #10848

[VestigeJ]

##Environment Details
Validated using COMMIT=647fc892dbce192a603ce0fcfde57445e7d4a4c4

Infrastructure

• Cloud

Node(s) CPU architecture, OS, and version:

Linux 6.4.0-150600.23.17-default x86_64 GNU/Linux
PRETTY_NAME="SUSE Linux Enterprise Server 15 SP6"

Cluster Configuration:

NAME              STATUS   ROLES                       AGE     VERSION
ip-2-2-2-98       Ready    control-plane,etcd,master   8m21s   v1.30.5+k3s-647fc892

Config.yaml:

node-external-ip: 2.2.2.98
token: YOUR_TOKEN_HERE
write-kubeconfig-mode: 644
debug: true
cluster-init: true
node-external-dns:
- cloudflare.com
- google.com
- arc.k3s.com

Validation

$ curl https://get.k3s.io --output install-"k3s".sh
$ sudo chmod +x install-"k3s".sh
$ sudo groupadd --system etcd && sudo useradd -s /sbin/nologin --system -g etcd etcd
$ sudo modprobe ip_vs_rr
$ sudo modprobe ip_vs_wrr
$ sudo modprobe ip_vs_sh
$ sudo printf "on_oovm.panic_on_oom=0 \nvm.overcommit_memory=1 \nkernel.panic=10 \nkernel.panic_ps=1 \nkernel.panic_on_oops=1 \n" > ~/90-kubelet.conf
$ sudo cp 90-kubelet.conf /etc/sysctl.d/
$ sudo systemctl restart systemd-sysctl
$ COMMIT=647fc892dbce192a603ce0fcfde57445e7d4a4c4
$ sudo INSTALL_K3S_COMMIT=$COMMIT INSTALL_K3S_EXEC=server ./install-k3s.sh
$ k apply -f https://k8s.io/examples/admin/dns/dnsutils.yaml
$ kgp dnsutils
$ kgn -o yaml | grep -i dns
$ k3s -v
$ k exec -it dnsutils -- nslookup -debug cloudflare.com > cloudflare
$ k exec -it dnsutils -- nslookup -debug google.com > google
$ k exec -it dnsutils -- nslookup -debug arc.k3s.com > arc

Results:

$ kgn -o yaml | grep -i dns

      k3s.io/node-args: '["server","--node-external-ip","2.2.2.98","--token","********","--write-kubeconfig-mode","644","--debug","true","--cluster-init","true","--node-external-dns","cloudflare.com","--node-external-dns","google.com","--node-external-dns","arc.k3s.com"]'

[brandond]

I missed this again this cycle because it was Done :/
Rescheduling to next month.

[VestigeJ]

Previous release node configuration behavior

$ kgn -o yaml | grep -i dns -B1 -A3

      k3s.io/internal-ip: 1.1.1.14
      k3s.io/node-args: '["server","--token","********","--write-kubeconfig-mode","644","--debug","true","--cluster-init","true","--embedded-registry","true","--node-external-dns","cloudflare.com","--node-external-dns","google.com","--node-external-dns","arc.k3s.com","--node-internal-dns","k3s.server.qa"]'
      k3s.io/node-config-hash: IG22GUHALZPSO6THTTTHA====
      k3s.io/node-env: '{}'
      node.alpha.kubernetes.io/ttl: "0"
--
    - names:
      - docker.io/rancher/mirrored-coredns-coredns@sha256:8461f69c1d8252a73f4c217ca17c75ac704af1c54c2332c199c637ab2815536a
      - docker.io/rancher/mirrored-coredns-coredns:1.11.3
      sizeBytes: 18561302
    - names:
      - docker.io/rancher/local-path-provisioner@sha256:f77fa34dd9d000daf6fd6029bf05de6b351b4fe4287cbc0ad2abb11a91df2ced

$ get_figs

=========== k3s config ===========
token: YOUR_TOKEN_HERE
write-kubeconfig-mode: 644
debug: true
cluster-init: true
embedded-registry: true
node-external-dns:
- cloudflare.com
- google.com
- arc.k3s.com
node-internal-dns:
- k3s.server.qa

$ k3s -v

k3s version v1.31.1+k3s1 (452dbbc1)
go version go1.22.6

Validated no configuration changed to reflect same configuration values

$ kgn -o yaml | grep -i dns -B1 -A3

DEBU[0000] Asset dir /var/lib/rancher/k3s/data/c88d88febb62fa475e3ca28a2ddb6c98856c37f75d98a6998124835561e9c104
DEBU[0000] Running /var/lib/rancher/k3s/data/c88d88febb62fa475e3ca28a2ddb6c98856c37f75d98a6998124835561e9c104/bin/kubectl [kubectl get nodes -o yaml]
      flannel.alpha.coreos.com/public-ip: 1.1.0.91
      k3s.io/external-dns: cloudflare.com,google.com,arc.k3s.com
      k3s.io/hostname: ip-1-1-0-91
      k3s.io/internal-dns: k3s.server.qa
      k3s.io/internal-ip: 1.1.0.91
      k3s.io/node-args: '["server","--token","********","--write-kubeconfig-mode","644","--debug","true","--cluster-init","true","--embedded-registry","true","--node-external-dns","cloudflare.com","--node-external-dns","google.com","--node-external-dns","arc.k3s.com","--node-internal-dns","k3s.server.qa"]'
      k3s.io/node-config-hash: IG2UHKXY4VAFFY2X====
      k3s.io/node-env: '{}'
      node.alpha.kubernetes.io/ttl: "0"
--
    - address: k3s.server.qa
      type: InternalDNS
    - address: cloudflare.com
      type: ExternalDNS
    - address: google.com
      type: ExternalDNS
    - address: arc.k3s.com
      type: ExternalDNS
    - address: ip-1-1-0-91
      type: Hostname
    allocatable:
--
    - names:
      - docker.io/rancher/mirrored-coredns-coredns@sha256:82979ddf442c593027a57239ad90616deb874e90c365d1a96ad508c2104bdea5
      - docker.io/rancher/mirrored-coredns-coredns:1.12.0
      sizeBytes: 20938299
    - names:
      - docker.io/rancher/mirrored-metrics-server@sha256:dccf8474fb910fef261d31d9483d7e4c1df7b86cf4d638fb6a7d7c88bd51600a

$ get_figs

=========== k3s config ===========
token: YOUR_TOKEN_HERE
write-kubeconfig-mode: 644
debug: true
cluster-init: true
embedded-registry: true
node-external-dns:
- cloudflare.com
- google.com
- arc.k3s.com
node-internal-dns:
- k3s.server.qa

$ k3s -v

k3s version v1.30.8-rc1+k3s1 (b43a365f)
go version go1.22.9