Firewall rule components (target, source, protocol) in GCP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the target in a firewall rule?

The target specifies which resources (like virtual machines) the firewall rule applies to. It acts like choosing which doors the rule controls.

beginner

What does the source mean in a firewall rule?

The source defines where the network traffic comes from, such as specific IP addresses or ranges. Think of it as the visitor's address trying to enter.

beginner

Why is the protocol important in a firewall rule?

The protocol tells the firewall which type of network traffic to allow or block, like TCP or UDP. It's like choosing which kind of mail (letters, packages) to accept.

intermediate

How do source and target work together in a firewall rule?

The source defines who is trying to connect, and the target defines who can be connected to. Together, they control who can talk to whom.

intermediate

What happens if you don't specify a protocol in a GCP firewall rule?

If no protocol is specified, the rule won't know which traffic to allow or block, so it won't work properly. Always specify the protocol to make the rule effective.

In a GCP firewall rule, what does the target specify?

A The resources the rule applies to

B The firewall's priority

C The network protocol used

D The source IP addresses allowed

The target defines which resources, like virtual machines, the firewall rule applies to.

What does the source field in a firewall rule represent?

A The destination IP addresses

B The protocol type

C The firewall rule name

D Where the traffic originates from

The source specifies where the network traffic comes from, such as IP addresses or ranges.

Which protocol is NOT commonly specified in firewall rules?

A TCP

B UDP

C HTTP

D ICMP

HTTP is an application protocol, not a network protocol like TCP, UDP, or ICMP used in firewall rules.

If a firewall rule has no target specified, what happens?

A It applies to all resources

B It applies to no resources

C It blocks all traffic

D It only allows traffic from the source

Without a target, the rule applies to all resources in the network.

Why must you specify a protocol in a firewall rule?

A To set the firewall's priority

B To identify the traffic type to allow or block

C To define the source IP

D To name the firewall rule

Specifying the protocol tells the firewall which traffic type to allow or block.

Explain the roles of target, source, and protocol in a GCP firewall rule.

Think about who is talking, who is listening, and what language they use.

Describe what happens if you omit the protocol in a firewall rule.

Imagine trying to filter mail without knowing if it's letters or packages.