Connection between EC2 instancies

0

How can I set a EC2 instancie as a web server to connect to another EC2 instancie running my aplication? I had verified the VPC, subnets and route tables. The two instancies are in the same VPC and subnet. But I had no success.

asked 22 days ago44 views
3 Answers
1

Check the security groups on the instances and make sure you are allowing the ports for the app.

Hope this helps.

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answered 22 days ago
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reviewed 22 days ago
1

Hi,

You should enable VPC Flow Logs to monitor the network traffic between your instances and identify any potential issues.

See doc to implement it: https://docs.aws.amazon.com/vpc/latest/userguide/flow-logs.html

You may also want to watch this video: https://www.youtube.com/watch?v=2PQIDssp9ts

Best,

Didier

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answered 22 days ago
0

To set up an EC2 instance as a web server to connect to another EC2 instance running your application within the same VPC and subnet, you need to ensure proper configuration of security groups and network access. Here are some steps to troubleshoot and establish the connection:

  1. Security Groups: Ensure that the security group for your web server instance allows outbound traffic to the application instance, and the security group for your application instance allows inbound traffic from the web server instance on the required ports.

  2. Private IP Addresses: Use the private IP addresses of the instances for communication within the same VPC and subnet. You can find these in the EC2 console.

  3. Network ACLs: Check if there are any Network ACLs applied to your subnet that might be blocking traffic between the instances.

  4. Instance-level firewalls: Ensure that any instance-level firewalls (like iptables on Linux) are configured to allow the necessary traffic.

  5. Application configuration: Verify that your web server is correctly configured to communicate with the application instance using the correct private IP address and port.

  6. EC2 Instance Connect: If you're having trouble accessing the instances to troubleshoot, you can use EC2 Instance Connect to securely connect to your instances without requiring public IP addresses.

  7. VPC Flow Logs: Enable VPC Flow Logs to monitor the network traffic between your instances and identify any potential issues.

If you've verified all these aspects and are still experiencing issues, you may want to use tools like tcpdump or netcat to diagnose network connectivity problems between the instances.

Remember, when connecting between instances in the same VPC and subnet, you should always use private IP addresses for better security and to avoid unnecessary internet data transfer charges.
Sources
Connect to your instances using EC2 Instance Connect Endpoint - Amazon Elastic Compute Cloud
Connect to an Amazon EC2 instance using EC2 Instance Connect Endpoint - Amazon Elastic Compute Cloud

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answered 22 days ago
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reviewed 22 days ago

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