Chapter 2 Advanced Routing for FortiOS 5.0 : Advanced Static Routing : Routing concepts : Troubleshooting static routing : Ping
  
Ping
Beyond the basic connectivity information, ping can tell you the amount of packet loss (if any), how long it takes the packet to make the round trip, and the variation in that time from packet to packet.
If there is no packet loss detected, your basic network connectivity is OK.
If there is some packet loss detected, you should investigate:
possible ECMP, split horizon, network loops
cabling to ensure no loose connections
 
If there is total packet loss, you should investigate:
hardware - ensure cabling is correct, and all equipment between the two locations is accounted for
addresses and routes - ensure all IP addresses and routing information along the route is configured as expected
firewalls - ensure all firewalls are set to allow PING to pass through
To ping from a Windows PC
1. Go to a DOS prompt. Typically you go to Start > Run, enter cmd and select OK.
2. Enter ping 10.11.101.100 to ping the default internal interface of the FortiGate unit with four packets.
To ping from an Apple computer
1. Open the Terminal.
2. Enter ping 10.11.101.100.
3. If the ping fails, it will stop after a set number of attempts. If it succeeds, it will continue to ping repeatedly. Press Control+C to end the attempt and see gathered data.
To ping from a Linux PC
1. Go to a command line prompt.
2. Enter “/bin/etc/ping 10.11.101.101”.