Creating compute instance from instance configuration - oci-python-sdk

I want to create a compute instance using oci-python-sdk in the same way as I would by clicking 'launch instance' in the "compute >> instance configurations >> instance configuration details" on the Oracle website.
I only found references to creating instances from custom images, but nothing on doing it from an existing configuration.

You can launch an instance configuration with launch_instance_configuration.
This example for launching an instance might help with a few more operations around the same: https://github.com/oracle/oci-python-sdk/blob/master/examples/launch_instance_example.py

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Terraform : How to fetch or destroy resources created by other means?

Sometimes I end up creating resources using AWS console due to some errors in Terraform or for lack of time. Can I list all my resources and destroy them? Basically a discovery of existing cloud resources and management of such ?
Ex: list my EC2 instances using Terraform and destroy when needed . How to achieve this?
Terraform is designed to ignore any existing objects that it didn't create because otherwise it would be risky to adopt Terraform an existing system with many existing objects and it would be impossible to decompose the infrastructure into different configurations for each subsystem without each one trying to destroy the objects being managed by the others.
Terraform doesn't have any facility for automatically detecting objects created outside of Terraform, but you can explicitly bind specific objects from your remote system to resource instances in your Terraform configuration using the terraform import command.
That command has some safeguards to try to prevent accidentally immediately deleting an object you've just imported if e.g. you make a typo of the resource instance address, and so unfortunately the design of this command is contrary to your goal: it won't let you just import something and run terraform apply to destroy it.
Instead, you'd need to:
Write a stub empty resource block for a resource of the appropriate type in your configuration.
Run terraform import to bind your existing real object to that empty resource block.
After the import succeeds, immediately remove the resource block to tell Terraform that you intend to delete the object.
Run terraform apply, and then Terraform should notice that it's tracking an object that is no longer mentioned in the configuration and propose to delete it.
Terraform is not the best tool for this job because it has essentially been designed to do the exact opposite of what you want to do, because typically users want to avoid destroying untracked objects to avoid disrupting neighboring systems.
However, you may be able to get the effect you want with some custom programming on your part, by writing a program that does something like the following:
Run terraform show -json in all of your configuration working directories to obtain a machine-readable description of the Terraform state in each one.
Decode the JSON state descriptions to find all of the resource instances of type aws_instance and collect a set of all of their id attribute values. This is the set of instances to keep.
Call the EC2 API DescribeInstances action to retrieve a list of all of the instances that actually exist. Collect a set of all of their IDs. This is the set of instances that exist.
Set-subtract the set of instances to keep from the set of instances that exist. The result is the set of instances to destroy.
If the set of instances to destroy isn't empty, call the EC2 API's TerminateInstances action to terminate every instance ID in that set.
This description is specific to Amazon EC2 instances. The same pattern could apply to objects of any other type, but there is no general solution that will work across all object types at once because the AWS API design doesn't work that way: each object type has its own separate operations for querying which objects exist and for destroying a particular object or set of objects.

Modifying the Top Right Information panel on a Windows 2016 EC2 Windows Instance

I am having an issue with my Amazon EC2 Instance. I want the information panel that appears on the top right of the instance when you access it (as displayed in the image below) to be modified. Is there a way to add lines of information from sources like one of the instance tags?
If someone has a solution to this that would be excellent. Thank you for taking the time to read this.
Example of where the information panel explained above is
I don't think you can modify it as such, it's a feature of the aws agent preinstalled on your instance. You could disable the feature in ec2config/ec2launch and then use a script to recreate the functionality with your custom data. The data displayed is accessible via http request from the instance metadata.
You could use a simple script using imagemagick, or PowerShell to create an image and set a registry key to set the new background.

How to create a ec2 instance in cloudfomration from the AMI of the instance which is also created by cloudformation

I have created a EC2 Instance using the cloud formation script and in that process I have executed around 20 commands in "AWS::CloudFormation::Init". This is a windows instance.
After that, I created a image from this and tried to create another EC2 instance using this image with couple of commands I wanted to be executed in "AWS::CloudFormation::Init".
This is giving me problem. The instance after getting created is not running the new commands which I specified in the template. But trying to run the commands which I specified while creating the old EC2Instance from which image was taken. This is through sysprep process which was given in one of the docs.
Is there any way to execute only the new commands and leaving out the old commands when the new image is created. I tried many alternatives. It is either executing old commands or none at all.
Have you stopped your instance before creating your image ? (like advised here).

nothing happens on libcloud create_node

I use libcloud to create a new node instance Amazon EC2.
conn.create_node returns me a valid instance and printing node.dict shows the expected values.
however when I check my EC2 dashboard the new machine does not appear there.
do I need my python app to stay open so that the node is actually created?
found it: the instance was actually created but for some reason the amazon did not show it even after refresh. logging out and in solved it.

AWS console not showing all instances during volume attach

I do the following using AWS web console:
Attach EBS volume-A to instance-A. Make some changes to data on volume-A and detach it
Launch new instance-B (in the same zone as instance-A)
Try attach volume-A to the new instance-B. But the new instance does not appear in the instances list during attach volume process (dialog box).
If I try the same attach using command line EC2 API (volume-A and instance-B), it works fine!
Do you know if this is a bug in AWS web console or am I doing something wrong in the console? Tried page refresh in Step #3 but it still would not list the new instance.
In order to attach, both volumes has to be in the same zone. So if you are going to attach a volume into a instance check the zone of the instance's attached volume. If those are not matching create a new instance with the same zone as the zone of the volume that you need to attached.
The volume and the instance have to be in the same region AND the same zone.
If you have a volume in us-east-1a and the instance in us-east-1b, you would need to move the volume to us-east-1b to make it work.
Even I had faced this problem yesterday and a day before. It looks like Amazon problem with their cache. Not sure WHY.
To bring back the stuff as is, I had to sign-out and make sure things are good. But it's always good to work with CLI, works better.
Although the user interface may not list the instance ID, you can attempt to add the volume anyway. If it's genuinely impossible (rather than a cache issue) you will get an error message.
Paste in the instance ID (i-xxxxxxx) manually then type your mount point (e.g. /dev/sdf) and click Attach.
For the benefit of others: some instance types do not support encrypted volumes, which may be why the instance doesn't appear in the list. I get the following error:
Error attaching volume: 'vol-12341234' is encrypted and 't2.medium' does not support encrypted volumes.

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