The Cisco IOS offers an "extended" mode of the ping command. This mode is entered by typing ping in privileged EXEC mode, without a destination IP address. A series of prompts are then presented as shown in the example below. Pressing Enter accepts the indicated default values. The example below illustrates how to force the source address for a ping to be 10.1.1.1 (see R2 in the figure); the source address for a standard ping would be 209.165.200.226. By doing this, the network administrator can verify remotely (from R2) that R1 has the route 10.1.1.0/24 in its routing table.
R2# ping
Protocol [ip]:
Target IP address: 192.168.10.1
Repeat count [5]:
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface: 10.1.1.1
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.10.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 36/97/132 ms
Entering a longer timeout period than the default allows for possible latency issues to be detected. If the ping test is successful with a longer value, a connection exists between the hosts, but latency may be an issue on the network.
Note that entering "y" to the "Extended commands" prompt provides more options that are useful in troubleshooting.