I have OS X and within it installed Ubuntu 13.04 via Parallels 8, and I also have iMac, within it I installed Ubuntu 12.04 (not Virtual Environment). So, now I have three OS - OS X, Ubuntu 13.04, and Ubuntu 12.04 (from here on I use OS name to specify each machine/environment).
When I tried to connect to Ubuntu 12.04 from OS X via SSH by running
ssh username@hostname, then it worked as expected. However, when I tried to type in the same command on Ubuntu 13.04 to try to connect to Ubuntu 12.04 via SSH, then the error
ssh: Could not resolve hostname myhostname: Name or service not known occurred.
Now I want to connect to Ubuntu 12.04 from Ubuntu 13.04, since some files I want to send out are stored on Ubuntu 13.04. However, it looks like even if I type in the exactly same command, I cannot connect on one environment but can on the other one. Why does this happen and how can I fix it?
I'm not entirely sure, but I'm worried about whether a machine which is allowed to be connected from another machine via SSH can connect itself to yet another one via SSH...
Here's a current situation:
OS X -> Ubuntu 12.04 --- succeed OS X -> Ubuntu 13.04 --- succeed Ubuntu 12.04 -> Ubuntu 13.04 --- failed Ubuntu 13.04 -> Ubuntu 12.04 --- failed
For your information I set up the configuration where I copy id_rsa.pub on my client and paste it in authorized_keys in my server.