Telnet connection with echo service succeeds for
127.0.0.1 host names, but fails with
::1 host name:
alex@u120432:~$ telnet localhost 7 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. 123 123 ^] telnet> q Connection closed. alex@u120432:~$ telnet ::1 7 Trying ::1... telnet: Unable to connect to remote host: Connection refused alex@u120432:~$
My own program trying to talk using IPv6 address fails as well. Why IPv6 address is rejected?
OS: Ubuntu 12.04 32 bit.
For any TCP/UDP server-client programs (not only telnet + echo) I tried different host names. Assuming that computer IP address is 10.90.185.73 (fe80::21b:21ff:fe5e:28af), I tested the following options:
localhost - works 127.0.0.1 - works ::1 - Connection refused 10.90.185.73 - works computer-name - works ::ffff:10.90.185.73 - works fe80::21b:21ff:fe5e:28af - Connection refused