- The many faces of an IP address
Valid IP addresses necessarily need not look "valid". IP addresses can be represented in idefinitely different ways, therefore it cannot be determined if a value is an IP address or not.
- How to ping IPv6 addresses
To ping IPv6 addresses, use the ping6 command along with the interface option -I. Example: ping -I en1 2a03:2880:f12f:83:face:b00c::25de.