AMI Deletion and Add new AMI to an existing EC2 - amazon-web-services

With a human error if an AMI associated to an EC2 got deleted and unrecovered. Is it possible to add new AMI to existing EC2 which is running? Does this destroy the existing EC2 and do we have to create new EC2?

Once an EC2 instance is created it doesn't matter at all if you delete the AMI. The AMI is not "in use" when an EC2 instance is running. The EBS volume(s) that were created when you launched the instance were copied from the AMI, at which point the AMI is no longer involved in the process at all.
You do not need to "add new AMI to existing EC2" which is impossible anyway.

You can create new AMI for that EC2, make sure you enable no reboot option before create AMI, other wise server will be rebooted.
You can use AWS CLI like below
INSTANCE_ID=`/opt/aws/bin/ec2-metadata -i | /usr/bin/awk '{print $2}'`
/usr/bin/aws ec2 create-image --no-reboot --instance-id $INSTANCEID --name "AMINAME" --description "description"
You can also use AWS console.
Creating an AMI will not destroy ANY EC2. it is backup for EC2 for DR, if EC2 fails you can launch new EC2 from updated AMI.
You can also use AWS AMI scheduledr -
https://aws.amazon.com/premiumsupport/knowledge-center/ec2-systems-manager-ami-automation/

Related

Weekly scheduled AMI backup of an Amazon EC2 instance with a root volume

I have DB instances in my AWS account. Many volumes are attached to one instance. I want to create an AMI of an Amazon EC2 instance with a root volume on weekly basis. At any point of time I should have the latest AMIs for an instance.
I have tried with systems manager. It’s creating snapshots of all volumes attached with the instance.
I have written a Bash script to create an AMI of an instance with a root volume. I need an approach to delete older images.
Note: The instance should not reboot the AMI creation
How can I update the script or is there is another way
to achieve it?
#!/bin/bash
root_device=$(aws ec2 describe-instances --instance-ids i-12345 --query 'Reservations[*].Instances[*].RootDeviceName' --output text)
echo root device is $root_device
devices=$(for i in $(aws ec2 describe-instances --instance-ids i-12345 --query 'Reservations[*].Instances[*].BlockDeviceMappings[*].DeviceName' --output text );
do if [ $i != $root_device ];
then echo DeviceName=$i,NoDevice=;
fi;
done)
aws ec2 create-image --instance-id i-12345 --block-device-mappings $devices --name "test-ami" --no-reboot
I have created a lambda function to create an AMI on a weekly basis. That solved my problem.
Another advantage is irrespective of the OS, I can use the function take AMI. :)

How to start and stop EC2 instance from Jenkins pipeline

I have a requirement :
I have 3 ec2 instance A, B, C in A instance i jenkins already installed in that jenkins i need to create a pipeline job which will start and stop instance B & C.
Is it possible ?
You should be able to install the Amazon EC2 Plugin and leverage it to start EC2 instances on demand, and correspondingly terminate them as they get unused.
Yes it is possible.
Install aws cli:
sudo apt-get install awscli
Configure aws credentails for aws cli:
aws configure
Start ec2 instance:
aws ec2 start-instances --instance-ids YOUR_INSTANCE_ID
Stop ec2 instance:
aws ec2 stop-instances --instance-ids YOUR_INSTANCE_ID
Keep in mind that in order to start/stop an instance your instance has to have an Amazon EBS volume as its root device.
Reference:
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/Stop_Start.html
http://shahzadlinux.blogspot.com/2019/04/how-to-stop-and-start-ec2-instance.html (Specific details for jenkins)

No ECS agent docker container in ECS optimised instance

I launched an ECS Optimised instance in ap-south-1 region of AWS from ami id: ami-0a8bf4e187339e2c1 using the link https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-optimized_AMI.html but there is no ecs agent present. Even /var/log/ecs directory is not present so I cannot check logs. I have correct cluster name configured in /etc/ecs/ecs.config
If you look at the instances in the EC2 console in AWS, can you see the AMI ID? Is it the AMI ID you expect?
Just to have a point of comparison, I just SSH'd to an ECS-optimized EC2 instances and I can see ecs-agent in a docker ps listing, I can see /var/log/ecs, so my first instinct is that this EC2 instance didn't end up using the AMI you expected it to.
If you want to check logs go to tasks and click on the task in which you wan to see logs and then click on logs yo will see the logs of your container.

How can I set existing EIPs to Auto scaled instances in AWS when they launch automatically?

I have cloud formation template which creates auto-scaling group with desired state 2. I need instances to be attached to existing eips when they get launched. How can I do this?
You need to write a custom user data script that assigns the elastic IP to the instance. You can not do this using CloudFormation templates yet. The AWS CLI to be used is: aws ec2 associate-address. For this, the best practice would be to assign and IAM role with ec2:AssociateAddress permission.
The command will look like this: aws ec2 associate-address --instance-id $INSTANCE_ID --allocation-id $ALLOCATION_ID --allow-reassociation
While the allocation id will need to be hardcoded in the template, you can get the instance id within the instance using the command: curl -s http://169.254.169.254/latest/meta-data/instance-id. Refer this thread
for more details.

Terminate an AWS EC2 instance without leaving a volume behind

I started an instance based on my AMI (based on Ubuntu 12.04 server) with the following command.
aws ec2 run-instances --image-id MY_AMI_ID --count 1 --instance-type t1.micro
What's surprising is, after I terminated the instance using the following command, it left an volume.
aws ec2 terminate-instances --instance-id MY_INSTANCE_ID
I would like to have the volume destroyed automatically, not sure if there is an easy option in the command line to do it.
Have you attached the volume after launching the instance?
As Amazon EC2 deletes all volumes that were attached during instance launch. Only volumes attached after instance is launched, will not be deleted.
Your AMI probably has the option set to not terminate block devices. You can adjust this behavior in your AMI by using the "delete-on-termination" option in AWS Console or the AWS CLI ec2-register command:
http://docs.amazonwebservices.com/AWSEC2/latest/CommandLineReference/ApiReference-cmd-RegisterImage.html
Found that
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/terminating-instances.html has an example
aws ec2 modify-instance-attribute --instance-id i-63893fed --block-device-mappings "[{\"DeviceName\": \"/dev/sda1\",\"Ebs\":{\"DeleteOnTermination\":true}}]"
That solves my problem: now after an instance is terminated, it will not leave a volume behind.