Which command applies an access-control list to an interface in the inbound direction?

Which command applies an access-control list to an interface in the inbound direction?

• A. access-group 101 in
• B. access-group 101 out
• C. access-group 101 in/out
• D. access-list 101 in

Answer: (A)

Applying an ACL to an interface is done by attaching the ACL to that interface with a direction. The inbound direction means the ACL is evaluated as traffic enters the interface, before it’s routed. So the command that attaches ACL 101 to the interface for inbound traffic is the one that uses the access-group form with in. Using out would apply the ACL to traffic leaving the interface, which is not described here, and the other options either don’t attach the ACL to the interface or use an invalid syntax.

Applying an ACL to an interface is done by attaching the ACL to that interface with a direction. The inbound direction means the ACL is evaluated as traffic enters the interface, before it’s routed. So the command that attaches ACL 101 to the interface for inbound traffic is the one that uses the access-group form with in. Using out would apply the ACL to traffic leaving the interface, which is not described here, and the other options either don’t attach the ACL to the interface or use an invalid syntax.