Listener rules and routing in AWS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a listener in AWS Elastic Load Balancer?

A listener is a process that checks for connection requests using a specific protocol and port. It forwards requests to target groups based on rules.

beginner

What do listener rules do in AWS load balancing?

Listener rules define how incoming requests are routed to target groups based on conditions like URL path or host headers.

beginner

Name two common conditions used in listener rules for routing.

Path-based routing (URL path) and host-based routing (domain name) are common conditions to decide where to send traffic.

intermediate

What happens if no listener rule matches an incoming request?

The request is routed to the default target group specified in the listener configuration.

intermediate

Why is the order of listener rules important?

Rules are evaluated in priority order. The first matching rule is applied, so order controls which rule takes effect when multiple match.

What does a listener in AWS Elastic Load Balancer do?

A Checks for connection requests and forwards them based on rules

B Stores data for the load balancer

C Creates virtual machines

D Monitors server CPU usage

A listener waits for connection requests on a port and protocol and forwards them to target groups based on rules.

Which condition can be used in listener rules to route traffic?

A User IP address

B Server CPU load

C URL path

D Database size

Listener rules commonly use URL path or host headers to route traffic.

If no listener rule matches a request, where is the traffic sent?

A To the first target group created

B Dropped immediately

C To a random server

D To the default target group

Requests not matching any rule go to the default target group set in the listener.

How are listener rules evaluated?

A By priority order, first match applies

B Randomly

C Alphabetically by target group name

D By server load

Listener rules have priorities; the first rule that matches the request is used.

What protocol and port does a listener use?

A Always HTTPS on port 443

B Specified by the user, e.g., HTTP on port 80

C FTP on port 21

D SMTP on port 25

Listeners are configured with a protocol and port like HTTP on 80 or HTTPS on 443.

Explain how listener rules control routing in AWS Elastic Load Balancer.

Think about how requests are matched and sent to servers.

Describe what happens when a request arrives at a load balancer listener with multiple rules.

Focus on the order and matching process.