SSH: use specific key when logging in
Two ways:
Specify the key in your ssh command, something like "ssh -i ~/.ssh/petri server.example.com"
Create a .ssh/config file with something like:
Host *
IdentityFile /home/petri/.ssh/petri
For more options, do a "man ssh_config" or "man ssh", depending on which you want to do.
Try this:
ssh -i /path/to/petri