When the directly connected PC cannot be pinged, perform the following operations:
Check whether the AR hardware interface is damaged. You can replace the AR interface.
Check PC settings including the IP address, gateway, and firewall.
Check the AR interface configuration. For example, check whether QoS commands are configured on an AR interface to filter ping packets.
First check whether ARP entries are normal and whether the AR learns the MAC address entry of the remote device. Check the statistics on the connected interface or obtain packets to determine ICMP packet receiving and sending.