Ping6

Ping6 is a network diagnostic utility used to test reachability and measure round-trip time to a host over an IPv6 network. It is the IPv6 counterpart to the IPv4 ping tool. Ping6 works by sending an ICMPv6 Echo Request message to the target and waiting for an ICMPv6 Echo Reply. The replies indicate whether the destination is reachable and provide latency and packet loss information when multiple probes are sent.

On many Unix-like systems, ping6 is a separate executable; on others, the same binary named ping can handle IPv6 when invoked with a suitable option, such as -6. Linux distributions often provide ping6 as a symlink to ping, but some distros require using ping -6. BSD-derived systems typically ship a distinct ping6 binary.

Usage and syntax are similar to the IPv4 ping, with some IPv6-specific considerations. Examples include: ping6 -c 4 2001:db8::1, which sends four probes to an IPv6 address; ping6 -c 10 fe80::1%eth0, which targets a link-local address with a specified interface. On Linux, you can also use ping -6 2001:db8::1 to force IPv6. Options such as -I to specify a source address or interface, -i to set the interval, and -W to set a timeout are commonly available.

Limitations and considerations include the fact that ICMPv6 traffic may be blocked by firewalls or routers, leading to false negatives. Some networks rate-limit ICMPv6 to prevent abuse. Successful ping6 results confirm reachability at the ICMPv6 level but do not guarantee end-to-end connectivity for other protocols.