can't join the second master on lab 16.2

Hi,
I´m having problems joining a second master to the cluster.
I ran this command and I get the next message:
vagrant@secondmaster:~$ sudo kubeadm join k8smaster:6443 --token lmcgs9.mwh1gukep4zrrsrb --discovery-token-ca-cert-hash sha256:c7f09153d5eb1ca4d1aaae5a72563b249893b0c0d5ba4c0f66ff309ab51cbd6e --control-plane --certificate-key 03b1178073e62dada4c46e06e9b9f60ce974806153f3af0e6783d0c410e2e4b9
[preflight] Running pre-flight checks
[WARNING Service-Docker]: docker service is not enabled, please run 'systemctl enable docker.service'
[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/
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
error execution phase preflight:
One or more conditions for hosting a new control plane instance is not satisfied.
unable to add a new control plane instance a cluster that doesn't have a stable controlPlaneEndpoint address
Please ensure that:
- The cluster has a stable controlPlaneEndpoint address.
- The certificates that must be shared among control plane instances are provided.
To see the stack trace of this error execute with --v=5 or higher
vagrant@secondmaster:~$
what should I check on this situation? how can i check my control plane has a stable controlPlaneEndpoint address?
Thanks in advance
Emiliano
Comments
-
Hi @emiliano.sutil,
The steps to join the second and third control-plane nodes are based on similar steps from earlier lab exercises when the worker node joined the primary control-plane node. These errors may be the result of an incomplete step either during software packages installation, or /etc/hosts file configured with an incorrect IP address for the "k8smaster" alias instead of the proxy IP and your request not reaching the primary API server.
I would suggest running through these steps one more time with a clean second control-plane node, ensuring that all steps are followed as closely as possible.
Regards,
-Chris0 -
Hi @chrispokorni
Thanks for your answer.I have repeated the process and I get the same problem.
the ips on the hosts files are:
k8smaster
10.128.1.20 k8smaster k8smasterha-proxy
10.128.1.20 k8smaster k8smastermaster:
10.128.1.20 k8smaster k8smastersecondmaster:
10.128.1.20 k8smaster k8smasterthe haproxy.cfg
backend k8sServers
balance roundrobin
server master 10.128.1.3:6443 checkthe 10.128.1.3 is the ip of my master
the http://10.128.1.20:9999/stats/
works fine and when I run
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8smaster Ready control-plane,master 57d v1.20.1
worker Ready 57d v1.20.1the stats updates, so I think the haproxy is properly configured.
any idea?
thanks in advance
0 -
Hi @emiliano.sutil,
Your issues are caused by your host naming convention, which is not aligned with the host naming convention presented in the lab guide.
The lab guide introduces three control-plane nodes:
master
,SecondMaster
, andThirdMaster
, withworker
andha-proxy
nodes. Thek8smaster
alias is just that, an alias assigned to themaster
node for the first 13 chapters (from Ch 3 to Ch 15) and then assigned to theha-proxy
node in Ch 16, to help the cluster identify the one node that captures traffic meant for the control-plane. In the beginning, themaster
node alone represents the control-plane and it is aliased withk8smaster
. In the HA chapter, theha-proxy
node becomes thek8smaster
once the control-plane grows from one to three nodes.In your situation, you have a node with the
k8smaster
hostname which has one IP address, and you also have thek8smaster
alias on theha-proxy
node with the 10.128.1.20 IP address.This configuration is confusing for cluster traffic management and needs to be cleaned up.
Regards,
-Chris0
Categories
- All Categories
- 51 LFX Mentorship
- 104 LFX Mentorship: Linux Kernel
- 576 Linux Foundation IT Professional Programs
- 304 Cloud Engineer IT Professional Program
- 125 Advanced Cloud Engineer IT Professional Program
- 53 DevOps Engineer IT Professional Program
- 61 Cloud Native Developer IT Professional Program
- 5 Express Training Courses
- 5 Express Courses - Discussion Forum
- 2K Training Courses
- 19 LFC110 Class Forum
- 7 LFC131 Class Forum
- 27 LFD102 Class Forum
- 157 LFD103 Class Forum
- 20 LFD121 Class Forum
- 1 LFD137 Class Forum
- 61 LFD201 Class Forum
- 1 LFD210 Class Forum
- LFD210-CN Class Forum
- 1 LFD213 Class Forum - Discontinued
- 128 LFD232 Class Forum
- LFD237 Class Forum
- 23 LFD254 Class Forum
- 611 LFD259 Class Forum
- 105 LFD272 Class Forum
- 1 LFD272-JP クラス フォーラム
- 1 LFD273 Class Forum
- 2 LFS145 Class Forum
- 24 LFS200 Class Forum
- 739 LFS201 Class Forum
- 1 LFS201-JP クラス フォーラム
- 11 LFS203 Class Forum
- 75 LFS207 Class Forum
- 300 LFS211 Class Forum
- 54 LFS216 Class Forum
- 47 LFS241 Class Forum
- 41 LFS242 Class Forum
- 37 LFS243 Class Forum
- 11 LFS244 Class Forum
- 36 LFS250 Class Forum
- 1 LFS250-JP クラス フォーラム
- LFS251 Class Forum
- 140 LFS253 Class Forum
- LFS254 Class Forum
- 1.1K LFS258 Class Forum
- 10 LFS258-JP クラス フォーラム
- 93 LFS260 Class Forum
- 132 LFS261 Class Forum
- 33 LFS262 Class Forum
- 80 LFS263 Class Forum
- 15 LFS264 Class Forum
- 11 LFS266 Class Forum
- 18 LFS267 Class Forum
- 17 LFS268 Class Forum
- 23 LFS269 Class Forum
- 203 LFS272 Class Forum
- 1 LFS272-JP クラス フォーラム
- LFS274 Class Forum
- LFS281 Class Forum
- 235 LFW211 Class Forum
- 172 LFW212 Class Forum
- 7 SKF100 Class Forum
- SKF200 Class Forum
- 903 Hardware
- 219 Drivers
- 74 I/O Devices
- 44 Monitors
- 116 Multimedia
- 209 Networking
- 101 Printers & Scanners
- 85 Storage
- 763 Linux Distributions
- 88 Debian
- 66 Fedora
- 15 Linux Mint
- 13 Mageia
- 24 openSUSE
- 142 Red Hat Enterprise
- 33 Slackware
- 13 SUSE Enterprise
- 357 Ubuntu
- 479 Linux System Administration
- 41 Cloud Computing
- 70 Command Line/Scripting
- Github systems admin projects
- 95 Linux Security
- 78 Network Management
- 108 System Management
- 49 Web Management
- 68 Mobile Computing
- 23 Android
- 30 Development
- 1.2K New to Linux
- 1.1K Getting Started with Linux
- 537 Off Topic
- 131 Introductions
- 217 Small Talk
- 21 Study Material
- 826 Programming and Development
- 278 Kernel Development
- 514 Software Development
- 928 Software
- 260 Applications
- 184 Command Line
- 3 Compiling/Installing
- 76 Games
- 316 Installation
- 61 All In Program
- 61 All In Forum
Upcoming Training
-
August 20, 2018
Kubernetes Administration (LFS458)
-
August 20, 2018
Linux System Administration (LFS301)
-
August 27, 2018
Open Source Virtualization (LFS462)
-
August 27, 2018
Linux Kernel Debugging and Security (LFD440)