How to send messages to virtual IPV6 Address?

Question

I want to send a messaged from Windows/Linux to a IPV6 virtual IP address which I had created on Ubuntu. Can anyone suggest the process to do so?

I created Virtual IPV6 in Ubuntu by the following Code: sudo ip -6 addr add 2002:1:1:1::10/64 dev eth0

And, for sending a message to IPV6 I used this Pyhton Code:

For Client:

# Echo client program
import socket
import sys

HOST = '2002:1:1:1::10'       # The remote host
PORT = 50007              # The same port as used by the server
s = None
for res in socket.getaddrinfo(HOST, PORT, socket.AF_UNSPEC, socket.SOCK_STREAM):
    af, socktype, proto, canonname, sa = res
    try:
        s = socket.socket(af, socktype, proto)
    except OSError as msg:
        s = None
        continue
    try:
        s.connect(sa)
    except OSError as msg:
        s.close()
        s = None
        continue
    break
if s is None:
    print('could not open socket')
    sys.exit(1)
s.sendall(b'Hello, world')
data = s.recv(1024)
s.close()
print('Received', repr(data))

For Server:

# Echo server program
import socket
import sys

HOST = '2002:1:1:1::10'               # Symbolic name meaning all available interfaces
PORT = 50007              # Arbitrary non-privileged port
s = None
for res in socket.getaddrinfo(HOST, PORT, socket.AF_UNSPEC,socket.SOCK_STREAM, 0, socket.AI_PASSIVE):
    af, socktype, proto, canonname, sa = res
    # The AF_* and SOCK_* constants are now AddressFamily and SocketKind IntEnum collections.
    try:
        s = socket.socket(af, socktype, proto)
    except OSError as msg:
        s = None
        continue
    try:
        s.bind(sa)
        s.listen(1)
    except OSError as msg:
        s.close()
        s = None
        continue
    break
if s is None:
    print('could not open socket')
    sys.exit(1)
conn, addr = s.accept()
print('Connected by', addr)
while True:
  data = conn.recv(1024)
  print(data)
  if not data: break
  conn.send(data) 
conn.close()

When I run this program I receive this error: [Errno 101] Network is unreachable. And, I cant ping the virtual IPV6.

Answer 1

IPv6 addresses starting with 2002: are 6to4 addresses. There are special rules on how those are used and routed. The address you are using is linked to IPv4 address 0.1.0.1, which is not a valid IPv4 address, so your IPv6 address is also invalid.

When using IPv6 you should use official addresses from your ISP. If you can't get addresses from your ISP and want addresses just for local use then use ULA addresses. You can generate those yourself. There are multiple websites that have an online generator that you can use.