VPC peering in GCP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a VPC peering connection between two networks.

GCP

gcloud compute networks peerings create [1] --network=network-a --peer-network=network-b

Drag options to blanks, or click blank then click option'

Apeer-connection-1

Bcreate-peer

Cnetwork-peering

Dvpc-link

Attempts:

3 left

💡 Hint

Common Mistakes

Using a command keyword instead of a name.

Using a generic term like 'vpc-link' which is not a valid peering name.

The peer-connection-1 is the name of the VPC peering connection you create. It uniquely identifies the peering.

2fill in blank

medium

Complete the code to list all VPC peerings in a network.

GCP

gcloud compute networks peerings list --network=[1]

Drag options to blanks, or click blank then click option'

Adefault

Bnetwork-a

Cvpc-peer

Dpeer-network

Attempts:

3 left

💡 Hint

Common Mistakes

Using a generic term like 'peer-network' instead of the actual network name.

Using 'default' when the peering is not in the default network.

The network-a is the name of the network whose peerings you want to list.

3fill in blank

hard

Fix the error in the command to delete a VPC peering connection.

GCP

gcloud compute networks peerings [1] peer-connection-1 --network=network-a

Drag options to blanks, or click blank then click option'

Adelete

Bremove

Cdestroy

Dterminate

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'remove' which is not a valid gcloud subcommand.

Using 'destroy' or 'terminate' which are invalid here.

The correct command to delete a VPC peering is delete.

4fill in blank

hard

Fill both blanks to create a VPC peering with export and import custom routes enabled.

GCP

gcloud compute networks peerings create peer-connection-2 --network=network-x --peer-network=network-y --export-custom-routes=[1] --import-custom-routes=[2]

Drag options to blanks, or click blank then click option'

Atrue

Bfalse

Cyes

Dno

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'yes' or 'no' which are invalid boolean values here.

Setting one flag to true and the other to false.

Both --export-custom-routes and --import-custom-routes flags should be set to true to enable route sharing.

5fill in blank

hard

Fill all three blanks to update a VPC peering to disable import and export of custom routes and set the peering name.

GCP

gcloud compute networks peerings update [1] --network=[2] --export-custom-routes=[3] --import-custom-routes=[3]

Drag options to blanks, or click blank then click option'

Apeer-connection-3

Bnetwork-z

Cfalse

Dtrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'true' instead of 'false' to disable routes.

Mixing up network and peering names.

The peering name is peer-connection-3, the network is network-z, and both import and export custom routes are set to false to disable them.

Practice

1.

What is the main purpose of VPC peering in Google Cloud?

easy

A. To create a firewall rule between two networks

B. To connect two private networks securely without using the internet

C. To provide public internet access to virtual machines

D. To enable automatic backups of virtual machines

Solution

1. Step 1: Understand VPC peering concept

   VPC peering connects two private networks directly, avoiding the public internet.

2. Step 2: Compare options with concept

   Only To connect two private networks securely without using the internet describes secure private network connection without internet.

3. Final Answer:

   To connect two private networks securely without using the internet -> Option B

4. Quick Check:

   VPC peering = secure private network connection [OK]

Hint: VPC peering = private network connection, no internet needed [OK]

Common Mistakes:

• Confusing VPC peering with firewall rules
• Thinking VPC peering provides internet access
• Assuming VPC peering is for backups

2.

Which of the following is the correct command to create a VPC peering connection from net-a to net-b in Google Cloud CLI?

gcloud compute networks peerings create PEERING_NAME --network=NETWORK --peer-network=PEER_NETWORK

easy

A. gcloud compute networks peerings create peer-ab --network=net-a --peer-network=net-b

B. gcloud compute networks peerings create net-a --network=peer-ab --peer-network=net-b

C. gcloud compute networks peerings create net-b --network=net-a --peer-network=net-b

D. gcloud compute networks peerings create peer-ab --peer-network=net-a --network=net-b

Solution

1. Step 1: Identify correct command syntax

   The command requires a peering name, the local network, and the peer network.

2. Step 2: Match parameters to networks

   gcloud compute networks peerings create peer-ab --network=net-a --peer-network=net-b correctly uses a peering name and assigns net-a as local network and net-b as peer network.

3. Final Answer:

   gcloud compute networks peerings create peer-ab --network=net-a --peer-network=net-b -> Option A

4. Quick Check:

   Correct CLI syntax = gcloud compute networks peerings create peer-ab --network=net-a --peer-network=net-b [OK]

Hint: Peering name first, then --network local, --peer-network remote [OK]

Common Mistakes:

• Swapping --network and --peer-network values
• Using network names as peering name
• Omitting required flags

3.

Given two VPC networks net-a and net-b peered together, which of the following statements about routing is true?

1. Each network must create routes to the other's IP ranges.
2. Routes are automatically shared by default.
3. Peering allows communication only if firewall rules permit.
4. Peering replaces the need for VPN connections.

medium

A. Only statement 2 and 3 are true

B. Only statement 1 and 3 are true

C. Only statement 1 and 2 are true

D. Only statement 3 and 4 are true

Solution

1. Step 1: Analyze routing and firewall requirements

   VPC peering automatically shares subnet routes by default. Firewall rules still control traffic.

2. Step 2: Evaluate statements

   Statement 1 is false (no manual route creation needed). Statements 2 and 3 are true. Statement 4 is not accurate (peering and VPN serve different purposes).

3. Final Answer:

   Only statement 2 and 3 are true -> Option A

4. Quick Check:

   Routes auto + firewall needed [OK]

Hint: Routes automatically shared; firewall rules still apply [OK]

Common Mistakes:

• Thinking routes must be manually created
• Ignoring firewall rules in peering
• Thinking peering always replaces VPN

4.

You created a VPC peering between net-a and net-b, but instances in net-a cannot reach instances in net-b. What is the most likely cause?

medium

A. The peering connection was created only on net-a side

B. The peering connection was created with the wrong peering name

C. The VPC networks have overlapping IP ranges

D. Firewall rules in net-b block incoming traffic from net-a

Solution

1. Step 1: Check common connectivity issues in VPC peering

   Firewall rules must allow traffic between peered networks; blocking rules prevent communication.

2. Step 2: Evaluate other options

   Wrong peering name or one-sided peering would prevent peering creation. Overlapping IP ranges prevent peering setup itself.

3. Final Answer:

   Firewall rules in net-b block incoming traffic from net-a -> Option D

4. Quick Check:

   Firewall blocking = connectivity failure [OK]

Hint: Check firewall rules first when peering connectivity fails [OK]

Common Mistakes:

• Ignoring firewall rules as cause
• Assuming peering auto-fixes IP conflicts
• Thinking peering is one-sided

5.

You have two VPC networks, net-a with CIDR 10.0.0.0/16 and net-b with CIDR 10.0.0.0/16. You want to peer them to share resources privately. What is the best approach?

hard

A. Create VPC peering directly between net-a and net-b despite overlapping CIDRs

B. Use VPN instead of VPC peering to connect the networks

C. Change one network's CIDR to a non-overlapping range before peering

D. Use shared VPC instead of peering for overlapping CIDRs

Solution

1. Step 1: Understand CIDR overlap restrictions in VPC peering

   VPC peering requires non-overlapping IP ranges to route traffic correctly.

2. Step 2: Choose solution for overlapping CIDRs

   Changing one network's CIDR to a non-overlapping range allows peering. VPN or shared VPC are alternatives but not direct peering solutions.

3. Final Answer:

   Change one network's CIDR to a non-overlapping range before peering -> Option C

4. Quick Check:

   Non-overlapping CIDRs required for peering [OK]

Hint: Peering needs unique IP ranges; change CIDR if overlapping [OK]

Common Mistakes:

• Trying to peer overlapping CIDRs directly
• Confusing VPN with peering
• Ignoring shared VPC as different concept