Jenkins kubernetes cloud service gettting SocketTimeoutException - linux

Question

I'm building a continuous integration pipeline through Jenkins to deploy microservices on a kubernetes cluster. I'm using minikube implementation.
I have some error in kubernetes agent configuration. I created a secretText credential to allow the agent to connect to my K8s cluster but when I test it I get this error:
Error testing connection https://<my_k8s_cluster_ip>:8443: java.net.SocketTimeoutException: connect timed out
I don't understand what the problem is.
K8s agent config
minikube config :
root#minikube:~# kubectl config view --minify=true
apiVersion: v1
clusters:
- cluster:
certificate-authority: /root/.minikube/ca.crt
extensions:
- extension:
last-update: Tue, 16 Feb 2021 23:57:36 CET
provider: minikube.sigs.k8s.io
version: v1.17.1
name: cluster_info
server: https://<minikube_ip>:8443
name: minikube
contexts:
- context:
cluster: minikube
extensions:
- extension:
last-update: Tue, 16 Feb 2021 23:57:36 CET
provider: minikube.sigs.k8s.io
version: v1.17.1
name: context_info
namespace: bargo
user: minikube
name: minikube
current-context: minikube
kind: Config
preferences: {}
users:
- name: minikube
user:
client-certificate: /root/.minikube/profiles/minikube/client.crt
client-key: /root/.minikube/profiles/minikube/client.key
Secret
root#minikube:~# kubectl get secrets
NAME TYPE DATA AGE
db-user-pass Opaque 2 2d18h
default-token-4f7lh kubernetes.io/service-account-token 3 3d
jenkins-token-4kdgr kubernetes.io/service-account-token 3 2d18h
Listening port
root#minikube:~# sudo netstat -tulpn | grep LISTEN
tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN 17207/systemd-resol
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 633/sshd: /usr/sbin
tcp 0 0 127.0.0.1:49153 0.0.0.0:* LISTEN 26838/docker-proxy
tcp 0 0 127.0.0.1:49154 0.0.0.0:* LISTEN 26851/docker-proxy
tcp 0 0 127.0.0.1:49155 0.0.0.0:* LISTEN 26865/docker-proxy
tcp 0 0 127.0.0.1:49156 0.0.0.0:* LISTEN 26879/docker-proxy
tcp6 0 0 :::22 :::* LISTEN 633/sshd: /usr/sbin
iptable result :
root#minikube:~# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:8443
Chain FORWARD (policy DROP)
target prot opt source destination
DOCKER-USER all -- anywhere anywhere
DOCKER-ISOLATION-STAGE-1 all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
DOCKER all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
DOCKER all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain DOCKER (2 references)
target prot opt source destination
ACCEPT tcp -- anywhere <my_server_ip> tcp dpt:8443
ACCEPT tcp -- anywhere <my_server_ip> tcp dpt:5000
ACCEPT tcp -- anywhere <my_server_ip> tcp dpt:2376
ACCEPT tcp -- anywhere <my_server_ip> tcp dpt:ssh
Chain DOCKER-ISOLATION-STAGE-1 (1 references)
target prot opt source destination
DOCKER-ISOLATION-STAGE-2 all -- anywhere anywhere
DOCKER-ISOLATION-STAGE-2 all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-ISOLATION-STAGE-2 (2 references)
target prot opt source destination
DROP all -- anywhere anywhere
DROP all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-USER (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Ubuntu Firewal status :
root#minikube:~# sudo ufw status verbose
Status: inactive
It's seam the Kubernetes API wasen't expose on port 8443. So i use this command :
kubectl proxy --port=8080 &
When i try it :
root#minikube:~# curl http://localhost:8080/api/
{
"kind": "APIVersions",
"versions": [
"v1"
],
"serverAddressByClientCIDRs": [
{
"clientCIDR": "0.0.0.0/0",
"serverAddress": "<minikube_ip>:8443"
}
]
}
root#minikube:~# curl http://127.0.0.1:8080/api/
{
"kind": "APIVersions",
"versions": [
"v1"
],
"serverAddressByClientCIDRs": [
{
"clientCIDR": "0.0.0.0/0",
"serverAddress": "<minikube_ip>:8443"
}
]
}
root#minikube:~# curl http://<minikube_ip>:8080/api/
curl: (7) Failed to connect to <minikube_ip> port 8080: Connection refused