I installed K3S on Ubuntu 18.04 as below:
curl -LO "https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl"
chmod +x ./kubectl
sudo mv ./kubectl /usr/local/bin/kubectl
kubectl version --client
curl -sfL https://get.k3s.io | sh -
sudo kubectl get nodes
However, when I do sudo kubectl get nodes, I get error below
ubuntu@ip-10-0-0-62:~$ sudo kubectl get nodes
The connection to the server localhost:8080 was refused - did you specify the right host or port?
I checked the running processes for three important ports
ubuntu@ip-10-0-0-62:~$ sudo lsof -i:6443
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
k3s-serve 2295 root 15u IPv6 28164 0t0 TCP *:6443 (LISTEN)
k3s-serve 2295 root 166u IPv6 31995 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-2.ap-southeast-2.compute.internal:45338 (ESTABLISHED)
k3s-serve 2295 root 168u IPv4 30182 0t0 TCP localhost:59284->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 173u IPv4 27307 0t0 TCP localhost:59176->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 177u IPv6 28302 0t0 TCP localhost:6443->localhost:59176 (ESTABLISHED)
k3s-serve 2295 root 182u IPv6 27361 0t0 TCP localhost:6443->localhost:59226 (ESTABLISHED)
k3s-serve 2295 root 184u IPv4 28411 0t0 TCP localhost:59226->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 185u IPv4 27363 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:47226->ip-10-0-0-62.ap-southeast-2.compute.internal:6443 (ESTABLISHED)
k3s-serve 2295 root 186u IPv6 27364 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-0-0-62.ap-southeast-2.compute.internal:47226 (ESTABLISHED)
k3s-serve 2295 root 188u IPv4 27368 0t0 TCP localhost:59230->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 190u IPv6 28414 0t0 TCP localhost:6443->localhost:59230 (ESTABLISHED)
k3s-serve 2295 root 194u IPv4 28418 0t0 TCP localhost:59232->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 195u IPv4 28419 0t0 TCP localhost:59234->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 196u IPv4 28420 0t0 TCP localhost:59236->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 197u IPv6 27405 0t0 TCP localhost:6443->localhost:59232 (ESTABLISHED)
k3s-serve 2295 root 198u IPv6 27406 0t0 TCP localhost:6443->localhost:59234 (ESTABLISHED)
k3s-serve 2295 root 199u IPv6 27407 0t0 TCP localhost:6443->localhost:59236 (ESTABLISHED)
k3s-serve 2295 root 204u IPv4 27411 0t0 TCP localhost:59238->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 205u IPv6 32305 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-4.ap-southeast-2.compute.internal:49256 (ESTABLISHED)
k3s-serve 2295 root 209u IPv4 28426 0t0 TCP localhost:59240->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 210u IPv4 27420 0t0 TCP localhost:59242->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 211u IPv6 34769 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-6.ap-southeast-2.compute.internal:56858 (ESTABLISHED)
k3s-serve 2295 root 212u IPv4 28428 0t0 TCP localhost:59246->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 213u IPv6 28429 0t0 TCP localhost:6443->localhost:59238 (ESTABLISHED)
k3s-serve 2295 root 214u IPv6 28430 0t0 TCP localhost:6443->localhost:59240 (ESTABLISHED)
k3s-serve 2295 root 215u IPv6 28431 0t0 TCP localhost:6443->localhost:59242 (ESTABLISHED)
k3s-serve 2295 root 216u IPv6 34771 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-6.ap-southeast-2.compute.internal:56860 (ESTABLISHED)
k3s-serve 2295 root 217u IPv6 28433 0t0 TCP localhost:6443->localhost:59246 (ESTABLISHED)
k3s-serve 2295 root 218u IPv4 27438 0t0 TCP localhost:59248->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 220u IPv6 28449 0t0 TCP localhost:6443->localhost:59248 (ESTABLISHED)
k3s-serve 2295 root 221u IPv6 28450 0t0 TCP localhost:6443->localhost:59250 (ESTABLISHED)
k3s-serve 2295 root 225u IPv4 28442 0t0 TCP localhost:59250->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 240u IPv4 28731 0t0 TCP localhost:59254->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 241u IPv4 28732 0t0 TCP localhost:59256->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 242u IPv6 28733 0t0 TCP localhost:6443->localhost:59254 (ESTABLISHED)
k3s-serve 2295 root 243u IPv6 28734 0t0 TCP localhost:6443->localhost:59256 (ESTABLISHED)
k3s-serve 2295 root 250u IPv4 29978 0t0 TCP localhost:59264->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 252u IPv6 29980 0t0 TCP localhost:6443->localhost:59264 (ESTABLISHED)
k3s-serve 2295 root 253u IPv4 29232 0t0 TCP localhost:59266->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 254u IPv4 29233 0t0 TCP localhost:59268->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 255u IPv6 29234 0t0 TCP localhost:6443->localhost:59266 (ESTABLISHED)
k3s-serve 2295 root 256u IPv6 29982 0t0 TCP localhost:6443->localhost:59268 (ESTABLISHED)
k3s-serve 2295 root 257u IPv4 29286 0t0 TCP localhost:59270->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 258u IPv6 29287 0t0 TCP localhost:6443->localhost:59270 (ESTABLISHED)
k3s-serve 2295 root 259u IPv6 34773 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-6.ap-southeast-2.compute.internal:56862 (ESTABLISHED)
k3s-serve 2295 root 260u IPv6 30184 0t0 TCP localhost:6443->localhost:59284 (ESTABLISHED)
k3s-serve 2295 root 261u IPv6 36154 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-6.ap-southeast-2.compute.internal:56864 (ESTABLISHED)
k3s-serve 2295 root 262u IPv6 31996 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-2.ap-southeast-2.compute.internal:45340 (ESTABLISHED)
k3s-serve 2295 root 263u IPv6 31998 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-2.ap-southeast-2.compute.internal:45342 (ESTABLISHED)
k3s-serve 2295 root 264u IPv6 32076 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-3.ap-southeast-2.compute.internal:35926 (ESTABLISHED)
k3s-serve 2295 root 265u IPv6 31674 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-3.ap-southeast-2.compute.internal:35928 (ESTABLISHED)
k3s-serve 2295 root 266u IPv6 32122 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-3.ap-southeast-2.compute.internal:35936 (ESTABLISHED)
k3s-serve 2295 root 267u IPv6 31675 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-3.ap-southeast-2.compute.internal:35930 (ESTABLISHED)
k3s-serve 2295 root 268u IPv6 31676 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-3.ap-southeast-2.compute.internal:35932 (ESTABLISHED)
k3s-serve 2295 root 269u IPv6 31677 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-3.ap-southeast-2.compute.internal:35934 (ESTABLISHED)
k3s-serve 2295 root 270u IPv6 31705 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-3.ap-southeast-2.compute.internal:35938 (ESTABLISHED)
k3s-serve 2295 root 271u IPv6 33226 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-4.ap-southeast-2.compute.internal:49258 (ESTABLISHED)
k3s-serve 2295 root 272u IPv6 33229 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:6443->ip-10-42-0-4.ap-southeast-2.compute.internal:49260 (ESTABLISHED)
k3s-serve 2295 root 273u IPv4 32308 0t0 TCP localhost:59490->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 274u IPv6 32309 0t0 TCP localhost:6443->localhost:59490 (ESTABLISHED)
k3s-serve 2295 root 275u IPv4 33234 0t0 TCP localhost:59492->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 276u IPv6 32311 0t0 TCP localhost:6443->localhost:59492 (ESTABLISHED)
k3s-serve 2295 root 277u IPv4 33645 0t0 TCP localhost:59586->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 279u IPv6 33646 0t0 TCP localhost:6443->localhost:59586 (ESTABLISHED)
k3s-serve 2295 root 283u IPv4 33650 0t0 TCP localhost:59592->localhost:6443 (ESTABLISHED)
k3s-serve 2295 root 286u IPv6 32741 0t0 TCP localhost:6443->localhost:59592 (ESTABLISHED)
ubuntu@ip-10-0-0-62:~$ sudo lsof -i:8472
ubuntu@ip-10-0-0-62:~$ sudo lsof -i:10250
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
k3s-serve 2295 root 224u IPv6 28440 0t0 TCP *:10250 (LISTEN)
k3s-serve 2295 root 226u IPv6 37502 0t0 TCP ip-10-0-0-62.ap-southeast-2.compute.internal:10250->ip-10-42-0-4.ap-southeast-2.compute.internal:47148 (ESTABLISHED)
Not sure what is the issue and how to resolve it.
