so I recently asked a question about how to provision instances that depend on each other. The answer I got was that I could instantiate the 3 instances, then have a null resource with a remote-exec provisioner that would update each instances.
It works great, except that in order to work my instances need to be configured to allow ssh. And since they are in a private subnet, I first need to allow ssh in a public instance that will then bootstrap my 3 instances. This bootstrap operation requires allowing ssh on 4 instances that really don't need to once the bootstrap is complete. This is not that bad, as I can still restrict the traffic to known ip/subnet, but I still thought it was worth asking if there was some ways to avoid that problem.
Can I update the security group of running instances in a single terraform plan? Example: Instantiate 3 instances with security_group X, provision them through ssh, then update the instances with security_group Y, thus disallowing ssh. If so, how? If not, are there any other solutions to this problem?
Thanks.
Based on the comments.
Instead of ssh, you could use AWS Systems Manager Run Command:
AWS Systems Manager Run Command lets you remotely and securely manage the configuration of your managed instances. Run Command enables you to automate common administrative tasks and perform ad hoc configuration changes at scale.
This would require making your instances to be recognized by AWS Systems Manager (SSM) which requires three things:
network connectivity to SSM service. Since your instances are in private subnet, they either have to connect to the SSM service using NAT gateway or VPC interface endpoints for SSM.
SSM Agent installed and running. This is usually not an issue as most offical AMI on AWS already have it setup.
Instance role with AmazonSSMManagedInstanceCore AWS managed policy.
Since run-command is not supported by terraform, you either have to use local-exec to run the command through AWS CLI, or through lambda function using aws_lambda_invocation.
Related
I need to retrieve existing data/properties of a given resource by using an AWS Cloudformation template. Is it possible? If it is how can I do it?
Example 1:
Output: Security Group ID which allows traffic on port 22
Example 2:
Output: Instance ID which use default VPC
AWS CloudFormation is used to deploy infrastructure from a template in a repeatable manner. It cannot provide information on any resources created by any methods outside of CloudFormation.
Your requirements seem more relevant to AWS Config:
AWS Config provides a detailed view of the configuration of AWS resources in your AWS account. This includes how the resources are related to one another and how they were configured in the past so that you can see how the configurations and relationships change over time.
An AWS resource is an entity you can work with in AWS, such as an Amazon Elastic Compute Cloud (EC2) instance, an Amazon Elastic Block Store (EBS) volume, a security group, or an Amazon Virtual Private Cloud (VPC).
Using your examples, AWS Config can list EC2 instances and any resources that are connected to the instances, such as Security Groups and VPCs. You can easily click-through these relationship and view the configurations. It is also possible to view how these configurations have changed over time, such as:
When EC2 instance changed state (eg stopped, running)
When rules changed on Security Groups
Alternatively, you can simply make API calls to AWS services to obtain the current configuration of resources, such as calling DescribeInstances to obtain a list of Amazon EC2 instances and their configurations.
As of the date of this question I'm using the most recent version of the AWS CLI (2.4.6) running on macOS. According to the v2 docs the Instances that are returned should include properties like InstanceLifecycle, Licenses, MetadataOptions -> PlatformDetails and several others that are missing for me. While I'm getting back most data, some fields are absent... I've tried this is two separate AWS accounts and I have admin IAM creds that I'm using locally, why does the aws ec2 describe-instances call not return all of the fields listed in the docs?
Not all outputs is available for every ec2 instance, it depends on the way of provisioning of your ec2 instances.
Ex:
InstanceLifecycle: is exclusive if you provisioned the ec2 instance as spot instance or reserved one.
Licenses: If you used BYOL when provisioning EC2 (Bring your own license)
Extra.. The docs describe every possible output from querying ec2 api endpoint, but it depends on the different parameters of your provisioned ec2 instance.
For example, try to provision a spot instance, and query the instance lifecycle.
What I want to do is use Ansible to create an ECS cluster, then create an EC2 instance and launch it into that cluster, but I can't seem to find a way to do that. I've had no trouble launching and configuring an EC2 instance on its own so far, but it's this next step that's totally blocking me.
The AWS documentation says I can create an EC2 instance with User Data to assign it to a cluster, but this doesn't seem to work when I use the user_data field of Ansible's ec2 module. This is what I have in that field:
#!/bin/bash
echo "ECS_CLUSTER=my-test-cluster" >> /etc/ecs/ecs.config
I feel like there must just be something I'm not seeing, or else some basic understanding I'm missing. I'm hoping someone can provide some pointers here.
Edit: I wasn't originally using the right ECS-optimized AMI, but even after starting an instance with the correct image I don't see a difference.
I think what you are missing is the proper policy on the instance to associate itself with the cluster. It sounds like you have the rest of it setup fine. I would safely assume that if you logged into the server and checked the ECS logs from the agent that you would see permission issues.
Take a look here http://docs.aws.amazon.com/AmazonECS/latest/developerguide/instance_IAM_role.html I had a similar issue myself before and setting the proper permissions fixed it.
Another possibility is that your instance doesn't have Internet access:
Container instances need external network access to communicate with the Amazon ECS service endpoint, so if your container instances do not have public IP addresses, then they must use network address translation (NAT) to provide this access.
I created a Amazon AWS EC2 instance under my account and made an website/ftp on it, now a new partner wants to move the instance under his company account so his company can pay the bills.
We can't change the instance IP because banks in the region are communicating with the server.
How can I move the instance to a different account without having to change anything on the configuration?
The short answer is: No, you cannot move an running instance from one account to another unless and ofcourse AWS Technical support has some magic available behind the curtains.
You can However, Create an AMI from this instance and share this AMI with other users/account. refer: http://aws.amazon.com/articles/530
To share or migrate EC2 instances from a source account to a target
account follow these steps:
Create a custom Amazon Machine Image (AMI)
from the instance you want to share or migrate. Be sure to include all
required EBS data volumes in the AMI.
Note: Data stored on instance store volumes isn't preserved in AMIs, and won't be on the instance store volumes of the instances
that you launch from the AMI.
Share the AMI with the target account
using either the EC2 console or the AWS Command Line Interface (CLI).
From the target account, find the AMI
using the EC2 console or the AWS CLI.
Launch a new instance from the shared AMI
on the target account.
Note: The private IP address of VPC instances will be different in the new account, unless you specifically set them during
launch.
Related information
Changing the Encryption State of Your Data
AWS CLI Command Reference (EC2)
Source: Transfer Amazon EC2 Instance
This is not possible.
AWS Support does not have access to copy Amazon EC2 resources or
manipulate any configuration options in AWS accounts. You can't
separate an AWS account from an Amazon.com account or transfer
resources between AWS accounts. It is possible to manually migrate
Amazon EC2 resources from one account to another by completing the
steps described here.
Source : https://aws.amazon.com/premiumsupport/knowledge-center/account-transfer-ec2-instance/
I'm working with several hundreds on EC2 instances in several AWS regions and accounts. You can move an EC2 instance to another AWS account, however, you can't move the Elastic IP and it will take up 16 steps with AWS CLI, if you want to migrate Tags and clone the Security Groups. I wrote a detailed post with the whole process at https://medium.com/#gmusumeci/how-to-move-an-ec2-instance-to-another-aws-account-e5a8f04cef21.
there are more than 10 steps involved in doing the cloud move. I would suggest you use Infrastructure as a Configuration (terraform and CloudFormation) or Infrastructure as a real code (pulumi and CDK)
however if you want to give a go at a nice tool I found called KopiCloud. Please feel welcome to try it and leave your comments below. Is good if you need to move instances on a quick lift and shift scenario.
You can re-think the design of having the banks in the region communicating to your servers via IP.
If the banks communicate using DNS names, you have much more flexibility to move your servers around.
You can also achieve improvements in high availability and resiliency by moving to DNS connections.
So a plan might be
Setup a DNS record for your existing server
Get the banks who connect to your server to connect via the DNS name
Setup your new server in the other account (other answers describe this)
Cut the banks over to your new server in the new account simply by updating the DNS record
I haven't tried load balancing across accounts, but that may be another option, which would give you HA as a bonus. By registering your current instance, and new instance in another account as targets with a load balancer and getting your clients to connect to the load balancer, you could cut over to the other account. The only part I haven't tried is registering targets in different accounts, but looks like this should be possible with an AWS Network Load Balancer
Is it possible to set up Cloudbees to deploy to an Amazon EC2 instance after a successful build?
Thanks,
W
Yes, but you don't provide many details of what you mean by "deploy". I suppose you mean using scp? If so, you must copy your Jenkins public key to an authorized keys file, and make sure that your security group rules allow CloudBees' build machines to talk to your EC2 instance.