For troubleshooting TKC (Tanzu Kubernetes Cluster) you may need to ssh into the TKC nodes. For doing ssh, you will need to first create a jumpbox pod under the supervisor namespace and from there you can ssh to the TKC nodes.
Here is the manual procedure: https://docs.vmware.com/en/VMware-vSphere/7.0/vmware-vsphere-with-tanzu/GUID-587E2181-199A-422A-ABBC-0A9456A70074.html
Following kubectl plugin creats a jumpbox pod under a supervisor namespace. You can exec into this jumpbox pod to ssh into the TKC VMs.
kubectl-jumpbox
#!/bin/bash
Help()
{
# Display Help
echo "Description: This plugin creats a jumpbox pod under a supervisor namespace. You can exec into this jumpbox pod to ssh into the TKC VMs."
echo "Usage: kubectl jumpbox SVNAMESPACE TKCNAME"
echo "Example: k exec -it jumpbox-tkc1 -n svns1 -- /usr/bin/ssh vmware-system-user@VMIP"
}
# Get the options
while getopts ":h" option; do
case $option in
h) # display Help
Help
exit;;
\?) # incorrect option
echo "Error: Invalid option"
exit;;
esac
done
kubectl create -f - <<EOF
apiVersion: v1
kind: Pod
metadata:
name: jumpbox-$2
namespace: $1 #REPLACE
spec:
containers:
- image: "photon:3.0"
name: jumpbox
command: [ "/bin/bash", "-c", "--" ]
args: [ "yum install -y openssh-server; mkdir /root/.ssh; cp /root/ssh/ssh-privatekey /root/.ssh/id_rsa; chmod 600 /root/.ssh/id_rsa; while true; do sleep 30; done;" ]
volumeMounts:
- mountPath: "/root/ssh"
name: ssh-key
readOnly: true
resources:
requests:
memory: 2Gi
volumes:
- name: ssh-key
secret:
secretName: $2-ssh #REPLACE YOUR-CLUSTER-NAME-ssh
EOF
Usage
- Place the plugin in the system executable path.
- I placed it in $HOME/.krew/bin directory in my laptop.
- Once you copied the plugin to the proper path, you can make it executable by: chmod 755 kubectl-jumpbox
- After that you should be able to run the plugin as: kubectl jumpbox SUPERVISORNAMESPACE TKCNAME
Example
❯ kg tkc -n vineetha-dns1-test
NAME CONTROL PLANE WORKER TKR NAME AGE READY TKR COMPATIBLE UPDATES AVAILABLE
tkc 1 3 v1.21.6---vmware.1-tkg.1.b3d708a 213d True True [1.22.9+vmware.1-tkg.1.cc71bc8]
tkc-using-cci-ui 1 1 v1.23.8---vmware.3-tkg.1 37d True True
❯
❯ kg po -n vineetha-dns1-test
NAME READY STATUS RESTARTS AGE
nginx-test 1/1 Running 0 29d
❯
❯
❯ kubectl jumpbox vineetha-dns1-test tkc
pod/jumpbox-tkc created
❯
❯ kg po -n vineetha-dns1-test
NAME READY STATUS RESTARTS AGE
jumpbox-tkc 0/1 Pending 0 8s
nginx-test 1/1 Running 0 29d
❯
❯ kg po -n vineetha-dns1-test
NAME READY STATUS RESTARTS AGE
jumpbox-tkc 1/1 Running 0 21s
nginx-test 1/1 Running 0 29d
❯
❯ k jumpbox -h
Description: This plugin creats a jumpbox pod under a supervisor namespace. You can exec into this jumpbox pod to ssh into the TKC VMs.
Usage: kubectl jumpbox SVNAMESPACE TKCNAME
Example: k exec -it jumpbox-tkc1 -n svns1 -- /usr/bin/ssh vmware-system-user@VMIP
❯
❯ kg vm -n vineetha-dns1-test -o wide
NAME POWERSTATE CLASS IMAGE PRIMARY-IP AGE
tkc-control-plane-8rwpk poweredOn best-effort-small ob-18900476-photon-3-k8s-v1.21.6---vmware.1-tkg.1.b3d708a 172.29.0.7 133d
tkc-using-cci-ui-control-plane-z8fkt poweredOn best-effort-small ob-20953521-tkgs-ova-photon-3-v1.23.8---vmware.3-tkg.1 172.29.13.130 37d
tkc-using-cci-ui-tkg-cluster-nodepool-9nf6-n6nt5-b97c86fb45mvgj poweredOn best-effort-small ob-20953521-tkgs-ova-photon-3-v1.23.8---vmware.3-tkg.1 172.29.13.131 37d
tkc-workers-zbrnv-6c98dd84f9-52gn6 poweredOn best-effort-small ob-18900476-photon-3-k8s-v1.21.6---vmware.1-tkg.1.b3d708a 172.29.0.6 133d
tkc-workers-zbrnv-6c98dd84f9-d9mm7 poweredOn best-effort-small ob-18900476-photon-3-k8s-v1.21.6---vmware.1-tkg.1.b3d708a 172.29.0.8 133d
tkc-workers-zbrnv-6c98dd84f9-kk2dg poweredOn best-effort-small ob-18900476-photon-3-k8s-v1.21.6---vmware.1-tkg.1.b3d708a 172.29.0.3 133d
❯
❯ k exec -it jumpbox-tkc -n vineetha-dns1-test -- /usr/bin/ssh vmware-system-user@172.29.0.7
The authenticity of host '172.29.0.7 (172.29.0.7)' can't be established.
ECDSA key fingerprint is SHA256:B7ptmYm617lFzLErJm7G5IdT7y4SJYKhX/OenSgguv8.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '172.29.0.7' (ECDSA) to the list of known hosts.
Welcome to Photon 3.0 (\m) - Kernel \r (\l)
13:06:06 up 133 days, 4:46, 0 users, load average: 0.23, 0.33, 0.27
36 Security notice(s)
Run 'tdnf updateinfo info' to see the details.
vmware-system-user@tkc-control-plane-8rwpk [ ~ ]$ sudo su
root [ /home/vmware-system-user ]#
root [ /home/vmware-system-user ]#
Hope it was useful. Cheers!
