Introduction
We might need to access the supervisor node via ssh for some extreme troubleshooting or configuration need for Tanzu Kubernetes Grid as service configured in vSphere7 and above. This blog illustrates the node access process in simple steps.
Initial Setup
We assume that Tanzu Kubernetes Grid as service is configured in vSphere7.
Step summary
- Login to vCenter
- Fetch the private key
- Access supervisor node via ssh
Login to vCenter
Need to get the FQDN or IP for the vCenter server. We would need to SSH as "root" user to the server.
❯ ssh [email protected]
VMware vCenter Server 7.0.3.00800
Type: vCenter Server with an embedded Platform Services Controller
([email protected]) Password:
root@vc01 [ ~ ]#Fetch private key
Since workload management is configured and supervisor cluster is configured in the current setup, so we can assume the private key would be stored securely in vCenter.
we can navigate and fetch the key as below :
root@vc01 [ ~ ]# cd /usr/lib/vmware-wcp
root@vc01 [ /usr/lib/vmware-wcp ]# ls -l | grep decryptk8pwd -i
-rwx------ 1 root root 3049 Jun 24 2022 decryptK8Pwd.py
root@vc01 [ /usr/lib/vmware-wcp ]# python decryptK8Pwd.py
Read key from file
Connected to PSQL
Cluster: domain-c8:cd257b1e-3809-4457-82fd-a442ef17836c
IP: 10.220.14.142
PWD: 3sFzX0sqkZ4jejuW/YTYGLBx67sxS/gvVmmH9Wko6ygYC/iXrKY1PlaakwJacLdO+g7bwJQ2FO08hnMnYDdxRYqsZv6XzVF3cAn0RlcEn1vmpI/DJVJZ1z3DVzRVYwBIaioxaErBcW6aTDY353b4LXxwvTerzMpmWweG6fID2Xc=
------------------------------------------------------------Access supervisor node via ssh
Tanzu Kubernetes Grid configures the supervisor cluster with Photon OS based VMs. these VMs can be located in vCenter or fetched as kubernetes nodes for supervisor cluster.
The operator admin can ssh login as "root" user into the VM with node FQDN or IP.
❯ k config get-contexts | grep ns1
CURRENT NAME CLUSTER AUTHINFO NAMESPACE
* ns1 10.220.14.162 wcp:10.220.14.162:[email protected] ns1
❯ k get no -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
4231ae00446076f7bf7a9bc740cff80c Ready control-plane,master 28h v1.22.6+vmware.wcp.2 10.220.14.173 <none> VMware Photon OS/Linux 4.19.229-2.ph3-esx containerd://1.5.9
4231f0a60627f2912eb6e11e340c17a4 Ready control-plane,master 28h v1.22.6+vmware.wcp.2 10.220.14.172 <none> VMware Photon OS/Linux 4.19.229-2.ph3-esx containerd://1.5.9
4231fef8f0b796154cf53e53133774f3 Ready control-plane,master 28h v1.22.6+vmware.wcp.2 10.220.14.174 <none> VMware Photon OS/Linux 4.19.229-2.ph3-esx containerd://1.5.9
❯ ssh [email protected]
([email protected]) Password:
Last login: Tue Jan 17 08:12:28 2023 from 10.109.145.56
08:54:32 up 1 day, 4:09, 0 users, load average: 0.68, 0.63, 0.63
26 Security notice(s)
Run 'tdnf updateinfo info' to see the details.
root@4231ae00446076f7bf7a9bc740cff80c [ ~ ]#NOTE: For ssh access to node, we would use the fetched private key from the vCenter
With above steps, admin user can login to the supervisor k8s node as root user and perform the required housekeeping or other operations check as required.