Using diagnostic tools
This chapter describes how to use the ping and traceroute utilities.
Ping
Use the ping utility to determine if a specific address is reachable.
A ping operation involves the following steps:
1.The source device sends ICMP echo requests to the destination device.
2.The destination device responds by sending ICMP echo replies to the source device after receiving the ICMP echo requests.
3.The source device displays related statistics after receiving the replies.
You can ping only the IP address of a device in the current software version.
If the source device does not receive an ICMP echo reply within the timeout time, it displays the following information:
•A prompt.
•Ping statistics.
If the source device receives ICMP echo replies within the timeout time, it displays the following information:
•Number of bytes for each echo reply.
•Message sequence number.
•Time to Live (TTL).
•Response time.
•Ping statistics.
Ping statistics include the following information:
•Number of echo requests sent.
•Number of echo replies received.
•Percentage of echo replies not received.
•Minimum, average, and maximum response time.
Traceroute
Traceroute retrieves the IP addresses of Layer 3 devices in the path to a specific destination. You can use traceroute to test network connectivity and identify failed nodes.
You can traceroute the IP address or the host name of a destination device. If the target host name cannot be resolved, a prompt appears.
A traceroute operation involves the following steps:
1.The source device sends a packet with a Time to Live (TTL) value of 1 to the destination device.
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