Verify the same host's IPv6 stack without sending traffic outside the host.
Finish after three echo requests.
Which command is appropriate?
::1 is IPv6 loopback, so ping -6 -c 3 ::1 sends exactly three requests within the same host.
Detailed explanation
ping -4 -c 3 ::1Incorrect. -4 forces IPv4 while ::1 is IPv6.
ping -6 -c 3 ::1Correct. It tests IPv6 loopback three times.
ping -6 -c 3 ff02::1Incorrect. ff02::1 is all-nodes link-local multicast, not host-only loopback.
ping -4 -c 3 0.0.0.0Incorrect. It uses IPv4 unspecified address and is not an IPv6 loopback test.
Try it yourself
An example you can run in a temporary verification environment.
ping -h 2>&1 | grep -E -- '-4|-6|-c' | head -n 2Expected result
IPバージョン選択と送信回数を示すhelp行Key points
- ::1 is IPv6 loopback
- -6 selects IPv6
- -c 3 limits requests
Notes
- Environment: iputils ping help / パケット送信なし
- Command output formatting can vary slightly by distribution or tool version.
- Run the example in a temporary directory or process when possible.
Foundation review
Interface counters
Kernel-maintained counts of packets, errors, and drops at an interface.
Socket
A local or remote endpoint associated with a transport protocol and process.
Path tracing
A diagnostic method that observes hops and path limits toward a destination.