Communicate with the IPv6 stack on the same host without sending traffic to a physical network.
Which IPv6 address is the loopback?
The IPv6 loopback address is ::1/128, serving the same-host role as IPv4 127.0.0.1.
Detailed explanation
::1Correct. ::1 is the IPv6 loopback address.
Correct. ::1 is the IPv6 loopback address.
::Incorrect. :: is the unspecified address.
Incorrect. :: is the unspecified address.
fe80::1Incorrect. fe80::1 is link-local.
Incorrect. fe80::1 is link-local.
ff02::1Incorrect. ff02::1 is a link-local all-nodes multicast address.
Incorrect. ff02::1 is a link-local all-nodes multicast address.
Try it yourself
An example you can run in a temporary verification environment.
python3 -c "import ipaddress; print(ipaddress.ip_address('::1').is_loopback)"Expected result
TrueKey points
- ::1 is loopback
- :: is unspecified
- Traffic stays on the host
Notes
- Environment: Python 3 ipaddress / 外部通信なし
- Command output formatting can vary slightly by distribution or tool version.
- Run the example in a temporary directory or process when possible.
Foundation review
Read the scope first
Check whether the command acts on the current shell, a new process, an existing process, or a file.
Verify the observable result
Use the supplied command and compare the output with the expected result.