Cloud VPN for hybrid connectivity in GCP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Cloud VPN in Google Cloud?

Cloud VPN is a service that securely connects your on-premises network to your Google Cloud Virtual Private Cloud (VPC) network using an encrypted tunnel over the public internet.

beginner

Why use Cloud VPN for hybrid connectivity?

Cloud VPN allows secure communication between your local data center and cloud resources, enabling a hybrid cloud setup where workloads can communicate safely across environments.

intermediate

What are the two main types of Cloud VPN in GCP?

The two types are Classic VPN and HA VPN. Classic VPN supports single tunnels, while HA VPN provides high availability with multiple tunnels and automatic failover.

intermediate

What is the role of IKE in Cloud VPN?

IKE (Internet Key Exchange) is a protocol used to set up a secure, authenticated communication channel between the two VPN endpoints before data is sent.

beginner

How does Cloud VPN ensure data security over the internet?

Cloud VPN encrypts data packets using IPsec protocols, which protect data confidentiality and integrity while it travels over the public internet.

What does Cloud VPN connect?

A Two on-premises data centers only

B Two Google Cloud projects only

C Your on-premises network to Google Cloud VPC

D Google Cloud to public internet without encryption

Cloud VPN securely connects your on-premises network to your Google Cloud VPC network.

Which Cloud VPN type offers high availability with automatic failover?

A HA VPN

B Classic VPN

C OpenVPN

D SSL VPN

HA VPN provides high availability with multiple tunnels and automatic failover.

What protocol does Cloud VPN use to encrypt data?

A HTTP

B IPsec

C FTP

D SMTP

Cloud VPN uses IPsec to encrypt data packets for secure transmission.

What is the purpose of IKE in Cloud VPN?

A To transfer files

B To assign IP addresses

C To monitor network traffic

D To establish a secure tunnel

IKE sets up a secure, authenticated communication channel between VPN endpoints.

Which of these is NOT a benefit of using Cloud VPN?

A Direct physical cable connection

B Encrypted data transfer

C Secure hybrid connectivity

D Supports on-premises to cloud communication

Cloud VPN uses the public internet with encryption, not a direct physical cable.

Explain how Cloud VPN enables hybrid connectivity between on-premises and Google Cloud.

Think about how two separate networks can talk securely over the internet.

Describe the difference between Classic VPN and HA VPN in Google Cloud.

Consider availability and reliability features.

Practice

1. What is the primary purpose of Cloud VPN in a hybrid cloud setup?

easy

A. To securely connect your local network to your cloud network over the internet

B. To store data backups in the cloud

C. To monitor cloud resource usage

D. To create virtual machines in the cloud

Solution

1. Step 1: Understand Cloud VPN function

   Cloud VPN creates a secure connection between local and cloud networks over the internet.

2. Step 2: Identify the main use case

   It is used to link networks privately, not for storage, monitoring, or VM creation.

3. Final Answer:

   To securely connect your local network to your cloud network over the internet -> Option A

4. Quick Check:

   Cloud VPN = secure hybrid network link [OK]

Hint: Cloud VPN links networks securely over internet [OK]

Common Mistakes:

• Confusing VPN with storage or monitoring services
• Thinking VPN creates cloud resources
• Assuming VPN is for data backup only

2. Which of the following is the correct way to specify the shared secret in a Cloud VPN tunnel configuration?

easy

A. shared-secret: mySecret123

B. shared_secret = mySecret123

C. secretShared: 'mySecret123'

D. sharedSecret: "mySecret123"

Solution

1. Step 1: Review Cloud VPN tunnel config syntax

   The shared secret is specified as a key-value pair with key 'sharedSecret' and a string value.

2. Step 2: Match correct syntax

   sharedSecret: "mySecret123" uses correct key and quotes for the secret string, matching expected config format.

3. Final Answer:

   sharedSecret: "mySecret123" -> Option D

4. Quick Check:

   Correct key and quotes for shared secret [OK]

Hint: Use exact key 'sharedSecret' with quotes [OK]

Common Mistakes:

• Using underscores or hyphens incorrectly in key names
• Omitting quotes around the secret string
• Swapping key name order

3. Given this Cloud VPN tunnel configuration snippet:

localTrafficSelector: ["10.0.0.0/24"]
remoteTrafficSelector: ["192.168.1.0/24"]

What traffic will be routed through the VPN tunnel?

medium

A. Only traffic within 192.168.1.0/24 subnet

B. All traffic from 10.0.0.0/24 to any IP

C. Traffic from 10.0.0.0/24 to 192.168.1.0/24 and vice versa

D. Traffic from 192.168.1.0/24 to 10.0.0.0/24 only

Solution

1. Step 1: Understand traffic selectors

   LocalTrafficSelector defines local IP ranges; remoteTrafficSelector defines remote IP ranges for the tunnel.

2. Step 2: Determine routed traffic

   Traffic between these two IP ranges (10.0.0.0/24 and 192.168.1.0/24) is routed through the VPN tunnel.

3. Final Answer:

   Traffic from 10.0.0.0/24 to 192.168.1.0/24 and vice versa -> Option C

4. Quick Check:

   Traffic between local and remote selectors routed [OK]

Hint: Traffic between local and remote selectors goes through VPN [OK]

Common Mistakes:

• Assuming all local traffic routes through VPN
• Confusing direction of traffic routing
• Ignoring remote traffic selector

4. You configured a Cloud VPN tunnel but the connection fails. Which of these is a common misconfiguration to check?

medium

A. Mismatched shared secret between local and cloud VPN gateways

B. Incorrect VM instance size in cloud

C. Missing firewall rule allowing HTTP traffic

D. Using a public IP address for the local network

Solution

1. Step 1: Identify common VPN tunnel failure causes

   Mismatched shared secrets prevent tunnel establishment as authentication fails.

2. Step 2: Evaluate other options

   VM size and HTTP firewall rules do not affect VPN tunnel setup; local network uses private IPs, not public IPs.

3. Final Answer:

   Mismatched shared secret between local and cloud VPN gateways -> Option A

4. Quick Check:

   Shared secret mismatch breaks VPN tunnel [OK]

Hint: Check shared secret matches on both sides [OK]

Common Mistakes:

• Ignoring shared secret mismatch
• Checking unrelated VM or firewall settings
• Confusing public and private IP usage

5. You want to connect your on-premises network (10.10.0.0/16) to your GCP VPC network (10.20.0.0/16) using Cloud VPN. Which setup step is essential to avoid routing conflicts?

hard

A. Assign public IPs to all on-premises devices

B. Ensure on-premises and VPC IP ranges do not overlap

C. Disable firewall rules on both sides

D. Use the same IP range for both networks for simplicity

Solution

1. Step 1: Understand IP range requirements for VPN

   Overlapping IP ranges cause routing confusion and packet loss between networks.

2. Step 2: Identify best practice

   Assign distinct, non-overlapping IP ranges to on-premises and cloud networks to ensure clear routing.

3. Final Answer:

   Ensure on-premises and VPC IP ranges do not overlap -> Option B

4. Quick Check:

   Non-overlapping IP ranges prevent routing conflicts [OK]

Hint: Avoid overlapping IP ranges for VPN networks [OK]

Common Mistakes:

• Using overlapping IP ranges causing routing issues
• Disabling firewalls unnecessarily
• Assigning public IPs to private network devices