If you have purchased a VPS server with CPANEL and its CSF firewall by doing a ping -t it might seem that there is a packet loss as shown in this image:
In reality, the default configuration of the CSF Firewall limits the response capacity of the CSF firewall to the ICMP protocol, i.e. the classic ping, the firewall limits the ping speed through a specific parameter, it is therefore not a technical problem of the network but only a protection that the firewall activates to defend itself from any DOS attacks.
The ICMP_IN_RATE parameter, by default limited to 1 / s. In fact, by raising this parameter the packet loss is eliminated.
You can find this parameter in the CSF Firewall configuration (requires root access to the server)
ICMP_IN_RATE = 20/s
