# K3s dns resolution failure **URL:** https://forums.suse.com/t/k3s-dns-resolution-failure/39091 **Category:** k3s, k3OS, and k3d **Created:** [September 29, 2022, 5:51am UTC](https://forums.suse.com/t/k3s-dns-resolution-failure/39091 "2022-09-29T05:51:45Z") **Posts on this page:** 3 **Page:** 1
### Author: ![kracozebr](https://avatars.discourse-cdn.com/v4/letter/k/da6949/32.png) [@kracozebr](https://forums.suse.com/u/kracozebr) #### Post date: [September 29, 2022, 5:51am UTC](https://forums.suse.com/t/k3s-dns-resolution-failure/39091/1 "2022-09-29T05:51:45Z")
I’m trying to configure k3s on my NVIDIA Jetson AGX Xavier **Environmental Info:** k3s version v1.24.4+k3s1 ([c3f830e](https://github.com/k3s-io/k3s/commit/c3f830e9b9ed8a4d9d0e2aa663b4591b923a296e)) go version go1.18.1 Node(s) CPU architecture, OS, and Version: Linux ubuntu 4.9.253-tegra SMP PREEMPT Sun Apr 17 02:37:44 PDT 2022 aarch64 aarch64 aarch64 GNU/Linux Cluster Configuration: 1 server The issue is that k3s can not resolve DNS resolution **Steps To Reproduce:** curl -sfL [https://get.k3s.io](https://get.k3s.io/) | sh -s - server --write-kubeconfig-mode 644 --cluster-init Check if dns resolutions works as follows ```auto kubectl run -it --rm --restart=Never busybox --image=busybox:1.28 -- nslookup kubernetes.default ``` And get: ```auto If you don't see a command prompt, try pressing enter. Address 1: 10.43.0.10 nslookup: can't resolve 'kubernetes.default' pod "busybox" deleted pod default/busybox terminated (Error) ``` Check the coredns logs ```auto for p in $(kubectl get pods --namespace=kube-system -l k8s-app=kube-dns -o name); do kubectl logs --namespace=kube-system $p; done ``` ```auto [WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server .:53 [WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server [INFO] plugin/reload: Running configuration SHA512 = b941b080e5322f6519009bb49349462c7ddb6317425b0f6a83e5451175b720703949e3f3b454a24e77f3ffe57fd5e9c6130e528a5a1dd00d9000e4afd6c1108d CoreDNS-1.9.1 linux/arm64, go1.17.8, 4b597f8 [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:57689->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:53306->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:38198->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:34448->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:39717->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:54180->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:35919->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:38218->8.8.8.8:53: i/o timeout [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:40765->8.8.8.8:53: i/o timeout [WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server [ERROR] plugin/errors: 2 4454268915698512202.3377740739522558627. HINFO: read udp 10.42.0.4:45094->8.8.8.8:53: i/o timeout [WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server [WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server ``` This is my config map of core-dns: ```auto kubectl -n kube-system get cm coredns -o yaml ``` ```auto apiVersion: v1 data: Corefile: | .:53 { errors health ready kubernetes cluster.local in-addr.arpa ip6.arpa { pods insecure fallthrough in-addr.arpa ip6.arpa } hosts /etc/coredns/NodeHosts { ttl 60 reload 15s fallthrough } prometheus :9153 forward . /etc/resolv.conf cache 30 loop reload loadbalance } import /etc/coredns/custom/*.server NodeHosts: | 192.168.0.103 ubuntu kind: ConfigMap metadata: annotations: objectset.rio.cattle.io/applied: H4sIAAAAAAAA/4yQwWrzMBCEX0Xs2fEf20nsX9BDybH02lMva2kdq1Z2g6SkBJN3L8IUCiVtbyNGOzvfzoAn90IhOmHQcKmgAIsJQc+wl0CD8wQaSr1t1PzKSilFIUiIix4JfRoXHQjtdZHTuafAlCgq488xUSi9wK2AybEFDXvhwR2e8QQFHCnh50ZkloTJCcf8lP6NTIqUyuCkNJiSp9LJP5czoLjryztTWB0uE2iYmvjFuVSFenJsHx6tFf41gvGY6Y0Eshz/9D2e0OSZfIJVvMZExwzusSf/I9SIcQQNvaG6a+r/XVdV7abBddPtsN9W66Eedi0N7aberM22zaHf6t0tcPsIAAD//8Ix+PfoAQAA objectset.rio.cattle.io/id: "" objectset.rio.cattle.io/owner-gvk: k3s.cattle.io/v1, Kind=Addon objectset.rio.cattle.io/owner-name: coredns objectset.rio.cattle.io/owner-namespace: kube-system creationTimestamp: "2022-09-23T09:06:05Z" labels: objectset.rio.cattle.io/hash: bce283298811743a0386ab510f2f67ef74240c57 name: coredns namespace: kube-system resourceVersion: "315" uid: 33a8ccf6-511f-49c4-9752-424859d67d70 ``` Check pods: ```auto kubectl -n kube-system get po -o wide ``` Output: ```auto coredns-b96499967-sct84 1/1 Running 1 (17h ago) 20h 10.42.0.6 ubuntu helm-install-traefik-crd-wrh5b 0/1 Completed 0 20h 10.42.0.3 ubuntu helm-install-traefik-wx7s2 0/1 Completed 1 20h 10.42.0.5 ubuntu local-path-provisioner-7b7dc8d6f5-qxjvs 1/1 Running 1 (17h ago) 20h 10.42.0.3 ubuntu metrics-server-668d979685-ngbmr 1/1 Running 1 (17h ago) 20h 10.42.0.5 ubuntu svclb-traefik-67fcd721-mz6sd 2/2 Running 2 (17h ago) 20h 10.42.0.2 ubuntu traefik-7cd4fcff68-j74gd 1/1 Running 1 (17h ago) 20h 10.42.0.4 ubuntu ``` Check services: ```auto kubectl -n kube-system get svc ``` Output: ```auto NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kube-dns ClusterIP 10.43.0.10 53/UDP,53/TCP,9153/TCP 20h metrics-server ClusterIP 10.43.178.64 443/TCP 20h traefik LoadBalancer 10.43.36.41 192.168.0.103 80:30268/TCP,443:30293/TCP 20h ``` I have a local net that was configured as follows. The internet is shared by laptop with ip 192.168.0.101 ![Screenshot from 2022-09-29 08-42-42](https://us1.discourse-cdn.com/flex022/uploads/suse/original/2X/7/772045f1af018893c1d3f5aa5f1272185b69b64d.png) I think I have network other lap or smth like this. Any suggestions to further debug? ---
### Author: ![ferlo003](https://avatars.discourse-cdn.com/v4/letter/f/5e9695/32.png) [@ferlo003](https://forums.suse.com/u/ferlo003) #### Post date: [December 17, 2022, 12:08am UTC](https://forums.suse.com/t/k3s-dns-resolution-failure/39091/2 "2022-12-17T00:08:24Z")
@kracozebr, I have this exact problem. Were you able to solve this issue. ---
### Author: ![kracozebr](https://avatars.discourse-cdn.com/v4/letter/k/da6949/32.png) [@kracozebr](https://forums.suse.com/u/kracozebr) #### Post date: [December 19, 2022, 5:04am UTC](https://forums.suse.com/t/k3s-dns-resolution-failure/39091/3 "2022-12-19T05:04:14Z")
HI, what I’ve done changed flag flannel backend, the comand I start k3s is: ```auto curl -sfL https://get.k3s.io | sh -s - server --write-kubeconfig-mode 644 --flannel-backend=ipsec ``` This worked for me. If it not works you can choose different flannel backend see docs: [Network Options | K3s](https://docs.k3s.io/installation/network-options)