Securely record SSH sessions on RHEL in a private VPC network

On this weblog submit, you’ll learn to report SSH classes on a Crimson Hat Enterprise Linux (RHEL) VSI in a non-public VPC community utilizing in-built packages. The VPC non-public community is provisioned via Terraform and the RHEL packages are put in utilizing Ansible automation. Moreover, you’ll learn to arrange a extremely accessible bastion host.

What’s session recording and why is it required?

A bastion host and a soar server are each safety mechanisms utilized in community and server environments to manage and improve safety when connecting to distant programs. They serve related functions however have some variations of their implementation and use circumstances. The bastion host is positioned in entrance of the non-public community to take SSH requests from public visitors and cross the request to the downstream machine. Bastion host and soar servers are susceptible to intrusion as a result of they’re uncovered to public visitors.

Session recording helps an administrator of a system to audit person SSH classes and ensure they adjust to regulatory necessities. Within the occasion of a safety breach, the administrator will wish to audit and analyze the person classes. That is vital for a security-sensitive system.

What’s a non-public VPC community?

A virtual private cloud is totally non-public if there isn’t any public ingress or outgress community visitors. In easy technical phrases, it’s non-public if there aren’t any public gateways on the subnets (non-public subnets) and no floating IPs on the Digital Server Situations (VSIs).

How do I hook up with the non-public VPC community?

Shopper-to-site VPN for VPC is without doubt one of the two VPN choices accessible on IBM Cloud, and it permits customers to connect with IBM Cloud sources via safe, encrypted connections.

The client-to-site VPN is very accessible, with two VPN servers which can be created in two totally different availability zones in the identical area. The bastions are extremely accessible as properly.

Conditions

Provision the non-public VPC community utilizing Terraform

• After you have the IBM Cloud Secrets Manager secret with the certificates, launch your terminal and set the next Terraform variables:

export TF_VAR_ibmcloud_api_key=<IBM_CLOUD_API_KEY>

export TF_VAR_secrets_manager_certificate_crn=<SECRET_CRN>

git clone https://github.com/VidyasagarMSC/private-vpc-network

cd terraform

• Run the Terraform instructions to provision the VPC sources (e.g., subnets, bastion hosts (VSIs), VPN, and many others.):

terraform init

terraform plan

terraform apply

Connect with client-to-site VPN

• As soon as the VPC sources are efficiently provisioned, it is advisable to obtain the VPN shopper profile by navigating to VPN servers page on IBM Cloud.
• Click on the Shopper-to-site servers tab after which on the identify of the VPN:

• Obtain the profile from the Shoppers tab.
• The VPN provisioned via Terraform makes use of certificates. Comply with the instructions here to connect with the OpenVPN Shopper.
• It’s best to see the profitable connection in your OpenVPN Shopper:

Confirm the SSH connection

• On a terminal, add the SSH non-public key to the SSH agent with the next command:

ssh-add <LOCATION_OF_PRIVATE_SSH_KEY> 

• Instance: ssh-add ~/.ssh/<NAME_OF_THE_PRIVATE_KEY>
• Run the next command to SSH into the RHEL VSI via a bastion host. You can be utilizing the non-public IP tackle of the bastion in Zone 1:

ssh -J root@10.10.0.13 root@10.10.128.13

• Keep in mind, you need to be related to the client-to-site VPN to entry the RHEL VSI via the bastion host.
• After SSH, It’s best to see directions to allow SSH session recording utilizing the TLOG bundle on RHEL.

Deploy session recording utilizing Ansible

To deploy the session recording answer, it is advisable to have the next packages put in on the RHEL VSI:

• tlog
• SSSD
• cockpit-session-recording

The packages will probably be put in via Ansible automation on all of the VSIs—each bastion hosts and RHEL VSI.

• Transfer to the Ansible folder:

cd ansible

• Create hosts.ini from the template file:

cp hosts_template.ini hosts.ini

• Run the Ansible playbook to put in the packages from an IBM Cloud non-public mirror/repository:

ansible-playbook main_playbook.yml -i hosts.ini --flush-cache

You may see in Determine 1 that after you SSH into the RHEL machine, you will notice a be aware saying: ATTENTION! Your session is being recorded!

Verify the session recordings, logs and experiences

In case you intently observe the messages post-SSH, you will notice a URL to the net console that may be accessed utilizing the machine identify or non-public IP over port 9090. To permit visitors on port 9090, within the Terraform code, change the worth of allow_port_9090 variable to true and run terraform apply. The most recent terraform apply will add ACL and safety group guidelines to permit visitors on port 9090.

• Now, open a browser and navigate to http://10.10.128.13:9090. To entry utilizing the VSI identify, it is advisable to arrange a non-public DNS (out of scope for this text). You want a root password to entry the net console:

• Navigate to Session Recording on the left-hand aspect to see the listing of session recordings. Together with session recordings, you possibly can examine the logs, diagnostic experiences, and many others.:

Really helpful studying

Conclusion

This text coated why session recording is required in bastion hosts for auditing and compliance and the way session recording could be arrange with the built-in RHEL packages utilizing Ansible Automation.

Whereas designing a secured digital non-public cloud community, you discovered the perfect practices in architecting a VPC non-public community. We additionally coated the necessity to construct extremely accessible VPN servers and bastion hosts. With the provisioning of cloud infrastructure utilizing Terraform and Ansible for session recording, you bought hands-on expertise.

Learn more about IBM Cloud VPC

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