VPC issue, unable to connect to any ec2 instances

Hello.

It is possible to recreate the default VPC.
If you want to use the default VPC, please create it using the steps in the document below.
https://docs.aws.amazon.com/vpc/latest/userguide/work-with-default-vpc.html#create-default-vpc

There are several possible reasons why you cannot SSH into EC2.
For example, you may not be able to connect because SSH is not allowed in the inbound rules of the EC2 security group, or there is no route to the Internet gateway in the route table of the subnet where EC2 is running.
I recommend checking the following documents for troubleshooting.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/TroubleshootingInstancesConnecting.html

Hii assist you with troubleshooting the SSH connectivity issue to your EC2 instances within your AWS account.

Troubleshooting Steps

Verify Security Group Rules:

• Ensure that the inbound rules of your security group allow SSH traffic (port 22) from your IP address or a specific range.
• You can modify the security group rules in the AWS Management Console or using the AWS CLI.

Check Instance State:

• Verify that your EC2 instances are in a running state. If they are stopped or terminated, start them to establish SSH connectivity.
• You can check the instance state in the AWS Management Console or using the AWS CLI.

Inspect Key Pair:

• Confirm that you are using the correct key pair to connect to your EC2 instances. Ensure that the private key file is accessible and has the correct permissions.
• You can manage your key pairs in the AWS Management Console or using the AWS CLI.

Verify Instance Configuration:

• Check the instance configuration to ensure that the SSH service is enabled and running. You can modify the instance configuration using the AWS Management Console or the AWS CLI.

Test Connectivity from Multiple Devices:

• Try connecting to your EC2 instances from different devices or networks to rule out local network issues.

Check AWS Service Health:

• Verify that there are no known service disruptions affecting AWS services, especially EC2 and VPC. You can check the AWS Service Health dashboard for any issues.

Related Documentation

AWS Security Groups: https://docs.aws.amazon.com/managedservices/latest/userguide/about-security-groups.html

AWS EC2 Instances: https://docs.aws.amazon.com/ec2/

AWS Key Pairs: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-key-pairs.html

AWS Service Health Dashboard: https://aws.amazon.com/premiumsupport/technology/aws-health