In IPv6 networks, when an administrator configures an access control list (ACL) to restrict remote access to a router, the ACL is typically applied to the vty (virtual terminal) lines to control access via SSH or Telnet. In the situation described, the administrator wants to monitor who else is trying to access the router and has used the log statement in the ACL. However, the access list is applied to the WAN interface, which controls incoming network traffic but does not apply to remote access attempts on the vty lines.
To resolve the issue, the access list needs to be applied to the vty lines to log remote access attempts, as this is where users try to connect for management purposes (via SSH or Telnet).
The ipv6 access-class command is used to apply the ACL to vty lines:
- in for controlling inbound access to the vty lines (remote access attempts).
- The log statement will then log access attempts, including those not permitted by the ACL.