Gfrktyl

I have a new Ubuntu 16.04 install. I want to ssh into a MacBook Pro via IPV6.

I can ping the Mac from Ubuntu, but it requires me to specify -I.

$ ping6 -c 1 -I enp0s25 fe80::14fc:cec5:c174:d88

PING fe80::14fc:cec5:c174:d88(fe80::14fc:cec5:c174:d88) from fe80::ba94:3d5e:9929:4c6e enp0s25: 56 data bytes

64 bytes from fe80::14fc:cec5:c174:d88: icmp_seq=1 ttl=64 time=0.378 ms

versus

$ ping6 -c 1 fe80::14fc:cec5:c174:d88

connect: Invalid argument

My Ubuntu has only one adapter and interface.

$ ifconfig

enp0s25   Link encap:Ethernet  HWaddr b8:ae:ed:77:91:fa 

...

lo        Link encap:Local Loopback 

...

I can ssh into the Mac from a Windows PC that uses PuTTY (plink). All three machines (MacBook, Windows, Ubuntu) are on the same network switch.

# bash on Windows

$ ssh test@fe80::14fc:cec5:c174:d88

Last login: Sat Nov 17 13:16:15 2018 from fe80::e119:5811:40e5:becf%en8

jws-mac:~ test$

On Ubuntu, this is the command I would like to work:

$ ssh -6 test@fe80::14fc:cec5:c174:d88

ssh: connect to host fe80::14fc:cec5:c174:d88 port 22: Invalid argument

It seems like it is a similar result to ping without -I switch. I don't want to use -b switch, because eventually I want to use git with IPV6 ssh url.

Pointers appreciated!

Since this is a link-local IPv6 address, the local interface identifier must be specified with the remote address.

$ ifconfig

enp0s25   Link encap:Ethernet  HWaddr b8:ae:ed:77:91:fa

...



$ ssh -6 test@fe80::14fc:cec5:c174:d88%enp0s25

or

ssh -6 user@remote-ipv6-address%local-interface-name

Note enp0s25 depends on the machine and is provided by ifconfig and plugged into ssh.

Here is an example of an ssh URL, for tools like git, assuming user git and subpath repos/test.git:

ssh://git@[fe80::14fc:cec5:c174:d88%25enp0s25]/repos/test.git

or

ssh://user@[remote-ipv6-address%25*local-interface*]/subpath

Note the % that separates address from interface has to be URL-encoded as %25.