CCNA ICND2 Lab15 - Access List

Lab Tips:

The ACL is a security solution that filters packets when they pass through a router. ACLs are divided into standard ACLs and extended ACLs. To pass the CCNA exam, please note the ip access-list command.

Topology:

Lab Requirements:

Standard ACL

P4S-R1 filters packets from P4S-R2.

P4S-R1 configuration:

1. Create an ACL

access-list 10 deny host 10.1.1.2

access-list 10 permit any

2. Apply the ACL to the interface

Interface serial 1/1

Ip access-group 10 in

P4S-R1 and P4S-R2 cannot communicate with each other. Run the ping command to check the application of the ACL.

Lab Process:

A. P4S-R1 filters only the Telnet requests from P4S-R2.

P4S-R1 configuration:

1. Create an ACL

access-list 100 deny tcp host 10.1.1.2 any eq 23

access-list 100 permit any any

2. Apply the ACL to the interface

interface serial 1/1

ip access-group 100 in

Enable the VTY password and privilege password on P4S-R1.

P4S-R2 can ping P4S-R1, but P4S-R2 cannot telnet into P4S-R1.

B. P4S-R1 can filter only ICMP packets from P4S-R2.

P4S-R1 configuration:

1. Create an ACL

access-list 101 deny icmp host 10.1.1.2 any

access-list 101 permit any any

2. Apply the ACL to the interface

interface serial 1/1

ip access-group 101 in