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# k3s
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Hi Team, Please i need your help on figuring out what the problem is for the dns resolution when setting up 
k3s
cluster. Here's the detailed information about my cluster machine:
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lsb_release -a
LSB Version:    core-11.1.0ubuntu4-noarch:security-11.1.0ubuntu4-noarch
Distributor ID: Ubuntu
Description:    Ubuntu 22.04.1 LTS
Release:        22.04
Codename:       jammy
k3s version
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kubectl version
Client Version: <http://version.Info|version.Info>{Major:"1", Minor:"23", GitVersion:"v1.23.8+k3s2", GitCommit:"fe3cecc219175ea85d7a95ed9e44349d94734bc7", GitTreeState:"clean", BuildDate:"2022-07-06T20:35:20Z", GoVersion:"go1.17.5", Compiler:"gc", Platform:"linux/amd64"}
Server Version: <http://version.Info|version.Info>{Major:"1", Minor:"23", GitVersion:"v1.23.8+k3s2", GitCommit:"fe3cecc219175ea85d7a95ed9e44349d94734bc7", GitTreeState:"clean", BuildDate:"2022-07-06T20:35:20Z", GoVersion:"go1.17.5", Compiler:"gc", Platform:"linux/amd64"}
Command to install and setup k3s
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curl -sfL <https://get.k3s.io> | INSTALL_K3S_EXEC="server --cluster-init --tls-san $(hostname) --bind-address=${current_ip} --advertise-address=${current_ip} --node-ip=${current_ip} --write-kubeconfig-mode 644 --flannel-iface=eth0 --node-external-ip=${current_ip}" INSTALL_K3S_VERSION="v1.23.8+k3s2" sh -s -
After running this command i get the following objects created and running
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kubectl get all -A
NAMESPACE     NAME                                          READY   STATUS      RESTARTS   AGE
kube-system   pod/coredns-d76bd69b-t48vp                    1/1     Running     0          10m
kube-system   pod/helm-install-traefik-crd-p75nj            0/1     Completed   0          10m
kube-system   pod/helm-install-traefik-q2g6d                0/1     Completed   1          10m
kube-system   pod/local-path-provisioner-6c79684f77-dgrw8   1/1     Running     0          10m
kube-system   pod/metrics-server-7cd5fcb6b7-dmkfm           1/1     Running     0          10m
kube-system   pod/svclb-traefik-8cdc35c6-kgqd9              2/2     Running     0          9m54s
kube-system   pod/traefik-df4ff85d6-lf2mb                   1/1     Running     0          9m54s

NAMESPACE     NAME                     TYPE           CLUSTER-IP      EXTERNAL-IP    PORT(S)                      AGE
default       service/kubernetes       ClusterIP      10.43.0.1       <none>         443/TCP                      10m
kube-system   service/kube-dns         ClusterIP      10.43.0.10      <none>         53/UDP,53/TCP,9153/TCP       10m
kube-system   service/metrics-server   ClusterIP      10.43.213.20    <none>         443/TCP                      10m
kube-system   service/traefik          LoadBalancer   10.43.108.209   192.168.1.27   80:31811/TCP,443:30979/TCP   9m54s

NAMESPACE     NAME                                    DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   NODE SELECTOR   AGE
kube-system   daemonset.apps/svclb-traefik-8cdc35c6   1         1         1       1            1           <none>          9m54s

NAMESPACE     NAME                                     READY   UP-TO-DATE   AVAILABLE   AGE
kube-system   deployment.apps/coredns                  1/1     1            1           10m
kube-system   deployment.apps/local-path-provisioner   1/1     1            1           10m
kube-system   deployment.apps/metrics-server           1/1     1            1           10m
kube-system   deployment.apps/traefik                  1/1     1            1           9m54s

NAMESPACE     NAME                                                DESIRED   CURRENT   READY   AGE
kube-system   replicaset.apps/coredns-d76bd69b                    1         1         1       10m
kube-system   replicaset.apps/local-path-provisioner-6c79684f77   1         1         1       10m
kube-system   replicaset.apps/metrics-server-7cd5fcb6b7           1         1         1       10m
kube-system   replicaset.apps/traefik-df4ff85d6                   1         1         1       9m54s

NAMESPACE     NAME                                 COMPLETIONS   DURATION   AGE
kube-system   job.batch/helm-install-traefik       1/1           20s        10m
kube-system   job.batch/helm-install-traefik-crd   1/1           18s        10m
Here's what I noticed, 1. The 
flannel service/deamonset
wasn't created even though i have specified it in the Install command. The first question I have is that, will this have any effect on how the cluster works !!!!!! Moving on, think i have a problem with the dns and when I check the logs for the 
CoreDNS
pod i see this error message
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kubectl logs coredns-d76bd69b-t48vp -n kube-system
[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/amd64, go1.17.8, 4b597f8
[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server
[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server
[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server
[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server
[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server
[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server
........
My questions here are 1. do i need to create this directory on my linux box a. also, do i need to create this in all the linux box i will be using in the cluster, that-is all master and worker nodes? 2. are there any prerequisite that i need to complete before i can use coredns in my cluster To confirm i have a problem with my dns i tried pinging ip and hostname of the 
traefik
pods. Pinging the ip works but not the hostname
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PINGING the IP
ping 10.42.0.8
PING 10.42.0.8 (10.42.0.8) 56(84) bytes of data.
64 bytes from 10.42.0.8: icmp_seq=1 ttl=64 time=0.034 ms
64 bytes from 10.42.0.8: icmp_seq=2 ttl=64 time=0.052 ms
....
^C
--- 10.42.0.8 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2039ms
rtt min/avg/max/mdev = 0.034/0.044/0.052/0.007 ms

PINGING THE Hostname
ping traefik-df4ff85d6-lf2mb
ping: traefik-df4ff85d6-lf2mb: Temporary failure in name resolution
Here's where the major question is 1. What exactly does the error message means a. 
ping: traefik-df4ff85d6-lf2mb: Temporary failure in name resolution
 Does anyone have any idea what i am doing wrong?
Also, i tried creating a test pod and when i ping the ip of that pod it works, but when i ping the hostname i get the same error
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