MAC update in vmk0 post vmnic0 replacement

 

esxcfg-advcfg -s 1 /Net/FollowHardwareMAC

Restart the ESXI 

https://kb.vmware.com/s/article/1031111

Snapshot related Issues

vim-cmd vmsvc/getallvms # To get all VM's running in ESXI

vim-cmd vmsvc/get.snapshotinfo [VMID] #Provide the VM number collected in above command

vim-cmd vmsvc/snapshot.get [VMID]

vim-cmd vmsvc/task_list # To get tasks list present in ESXI

vim-cmd vmsvc/task_info TASK_NAME # To get information about the given task




# vim-cmd vmsvc/snapshot.create [VmId] [snapshotName] [snapshotDescription] [includeMemory] [quiesced]

Example:

# vim-cmd vmsvc/snapshot.create 22 Demo-Snapshot02 "Snapshot Demo 2 Two" 0 0

# vim-cmd vmsvc/snapshot.removeall [VMID] # To remove all Snapshots

https://www.theaccessgroup.com/en-gb/blog/chs-hidden-vmware-snapshots/

Troubleshooting

1.  Snapshot related Issues
2. MAC update in vmk0 post vmnic0 replacement

DRS

 DRS

• The main goal of DRS is to ensure that VMs and their applications are always getting the compute resources that they need to run efficiently
• DRS monitors the cluster balance state once every five minutes, by default, and then takes the necessary actions to fix any imbalance.
• When a VM is being powered up in a DRS cluster, DRS runs its algorithm to determine the right ESXi host for it to be powered up on
• 
  

vSphere

 vSphere

• What is vSphere 
• ESXI
• DRS
• HA
• AD Intigration
• VCSA Certificate Renewal 
• Troubleshooting 

Kubernetes

 

Imperative Commands with Kubectl

While you would be working mostly the declarative way - using definition files, imperative commands can help in getting one time tasks done quickly, as well as generate a definition template easily. This would help save considerable amount of time during your exams.

Before we begin, familiarize with the two options that can come in handy while working with the below commands:

--dry-run: By default as soon as the command is run, the resource will be created. If you simply want to test your command , use the --dry-run=client option. This will not create the resource, instead, tell you whether the resource can be created and if your command is right.

-o yaml: This will output the resource definition in YAML format on screen.

Use the above two in combination to generate a resource definition file quickly, that you can then modify and create resources as required, instead of creating the files from scratch.

POD

Create an NGINX Pod

kubectl run nginx --image=nginx

Generate POD Manifest YAML file (-o yaml). Don't create it(--dry-run)

kubectl run nginx --image=nginx --dry-run=client -o yaml

Deployment

Create a deployment

kubectl create deployment --image=nginx nginx

Generate Deployment YAML file (-o yaml). Don't create it(--dry-run)

kubectl create deployment --image=nginx nginx --dry-run=client -o yaml

Generate Deployment with 4 Replicas

kubectl create deployment nginx --image=nginx --replicas=4

You can also scale a deployment using the kubectl scale command.

kubectl scale deployment nginx --replicas=4

Another way to do this is to save the YAML definition to a file and modify

kubectl create deployment nginx --image=nginx --dry-run=client -o yaml > nginx-deployment.yaml

You can then update the YAML file with the replicas or any other field before creating the deployment.

Service

Create a Service named redis-service of type ClusterIP to expose pod redis on port 6379

kubectl expose pod redis --port=6379 --name redis-service --dry-run=client -o yaml

(This will automatically use the pod's labels as selectors)

Or

kubectl create service clusterip redis --tcp=6379:6379 --dry-run=client -o yaml (This will not use the pods labels as selectors, instead it will assume selectors as app=redis. You cannot pass in selectors as an option. So it does not work very well if your pod has a different label set. So generate the file and modify the selectors before creating the service)

Create a Service named nginx of type NodePort to expose pod nginx's port 80 on port 30080 on the nodes:

kubectl expose pod nginx --type=NodePort --port=80 --name=nginx-service --dry-run=client -o yaml

(This will automatically use the pod's labels as selectors, but you cannot specify the node port. You have to generate a definition file and then add the node port in manually before creating the service with the pod.)

Or

kubectl create service nodeport nginx --tcp=80:80 --node-port=30080 --dry-run=client -o yaml

(This will not use the pods labels as selectors)

Both the above commands have their own challenges. While one of it cannot accept a selector the other cannot accept a node port. I would recommend going with the kubectl expose command. If you need to specify a node port, generate a definition file using the same command and manually input the nodeport before creating the service.

Reference:

https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands

https://kubernetes.io/docs/reference/kubectl/conventions/