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kubeadm join ISSUE: [discovery] Failed to request cluster info, will try again:
dmccuk
Posts: 3
Hi,
I've been trying to add a worker node to the cluster. I've followed the doc but I'm hitting this issue and I can't find a way past it. I've obviously missed something. Here is the command and error:
PART1
[email protected]:~# kubeadm join --token od1wg1.a9wd79hstxz3ll4z 172.31.19.37:6443 --discovery-token-ca-cert-hash sha256:4aed0a78c329495d91e031a336668ccaf07528c84b7120f230f2f 161a98e7693 --v=2 I1018 15:46:36.761858 25485 join.go:367] [preflight] found NodeName empty; using OS hostname as NodeName I1018 15:46:36.761930 25485 initconfiguration.go:105] detected and using CRI socket: /var/run/dockershim.sock [preflight] Running pre-flight checks I1018 15:46:36.762004 25485 preflight.go:90] [preflight] Running general checks I1018 15:46:36.762037 25485 checks.go:254] validating the existence and emptiness of directory /etc/kubernetes/manifests I1018 15:46:36.762083 25485 checks.go:292] validating the existence of file /etc/kubernetes/kubelet.conf I1018 15:46:36.762124 25485 checks.go:292] validating the existence of file /etc/kubernetes/bootstrap-kubelet.conf I1018 15:46:36.762140 25485 checks.go:105] validating the container runtime I1018 15:46:36.806159 25485 checks.go:131] validating if the service is enabled and active [WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/ I1018 15:46:36.858635 25485 checks.go:341] validating the contents of file /proc/sys/net/bridge/bridge-nf-call-iptables I1018 15:46:36.858693 25485 checks.go:341] validating the contents of file /proc/sys/net/ipv4/ip_forward I1018 15:46:36.858729 25485 checks.go:653] validating whether swap is enabled or not I1018 15:46:36.858762 25485 checks.go:382] validating the presence of executable ip I1018 15:46:36.858793 25485 checks.go:382] validating the presence of executable iptables I1018 15:46:36.858813 25485 checks.go:382] validating the presence of executable mount I1018 15:46:36.858834 25485 checks.go:382] validating the presence of executable nsenter I1018 15:46:36.858851 25485 checks.go:382] validating the presence of executable ebtables I1018 15:46:36.858870 25485 checks.go:382] validating the presence of executable ethtool I1018 15:46:36.858891 25485 checks.go:382] validating the presence of executable socat I1018 15:46:36.858910 25485 checks.go:382] validating the presence of executable tc I1018 15:46:36.858927 25485 checks.go:382] validating the presence of executable touch I1018 15:46:36.858950 25485 checks.go:524] running all checks I1018 15:46:36.873553 25485 checks.go:412] checking whether the given node name is reachable using net.LookupHost I1018 15:46:36.882411 25485 checks.go:622] validating kubelet version I1018 15:46:36.937337 25485 checks.go:131] validating if the service is enabled and active I1018 15:46:36.943627 25485 checks.go:209] validating availability of port 10250 I1018 15:46:36.943778 25485 checks.go:292] validating the existence of file /etc/kubernetes/pki/ca.crt I1018 15:46:36.943797 25485 checks.go:439] validating if the connectivity type is via proxy or direct I1018 15:46:36.943826 25485 join.go:427] [preflight] Discovering cluster-info I1018 15:46:36.944224 25485 token.go:200] [discovery] Trying to connect to API Server "172.31.19.37:6443" I1018 15:46:36.944877 25485 token.go:75] [discovery] Created cluster-info discovery client, requesting info from "https://172.31.19.37:6443" I1018 15:47:06.945803 25485 token.go:83] [discovery] Failed to request cluster info, will try again: [Get https://172.31.19.37:6443/api/v1/namespaces/kube-public/configmaps/cluster-info: dial tcp 172.31.19.37:6443: i/o timeout] I1018 15:47:41.946445 25485 token.go:83] [discovery] Failed to request cluster info, will try again: [Get https://172.31.19.37:6443/api/v1/namespaces/kube-public/configmaps/cluster-info: dial tcp 172.31.19.37:6443: i/o timeout] ^C [email protected]:~#
I'm able to telnet to port 22 from the worker to the master:
[email protected]:~# telnet 172.31.19.37 22 Trying 172.31.19.37... Connected to 172.31.19.37. Escape character is '^]'. SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.8 ^] telnet> quit Connection closed. [email protected]:~# [email protected]:~# telnet 172.31.19.37 6443 Trying 172.31.19.37...
PART2 with more details follows once it gets approved.
0
Answers
Hi @dmccuk,
Similar discussions have been posted recently in the forum, where a second node fails to join the cluster.
From your output, the failure is a timeout when accessing port 6443 on the master node.
Port 22 is irrelevant in this scenario since Kubernetes uses lots of different individual port numbers and port ranges - and 6443 is one of them.
Read carefully the special instructions at the beginning of Lab exercise 3.1. These instructions are critical in setting up your infrastructure's networking (firewall rules) for inter-node communication.
Regards,
-Chris
Hi Chris,
Thanks for your message. I worked out what I hadn't done. I'll write it here so others can benefit:
1) In AWS, create a new security group and open up all the ports.
2) Select one of your Kubernetes instances --> actions --> networking
3) Tick the new kubernetes group, adding it to your instance.
4) Repeat for all the other kubernetes instances.
5) Retry the failing command.
I hope that helps.
Dennis
PART2:
The FW is off on both the worker and the master:
WORKER:
MASTER:
Here is the master namespaces:
I've been through this link and the steps I'm taking are identical:
https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/#pod-network
The TOKEN and openssl key I'm using in my join command:
NETSTAT from the master:
I'm stuck! If anyone can help I would really appreciate it!