You have at least 2 options to choose the key used by ssh. for instance.
Method 1 — Specify the key on the command line with the
The command line to use is:
ssh -i ~/.ssh/key1 firstname.lastname@example.org
Method 2 — Use the ssh configuration file. This is useful when you don't have the option
-iavailable, such as when using git, rsync, or lftp.
You can add to your
~/.ssh/configthe following lines
Host example.com IdentityFile ~/.ssh/key1
This tells ssh to use the key file .
~/.ssh/key1 for the host