How to choose an SSH key for a specific host

You have at least 2 options to choose the key used by ssh. for instance.~/.ssh/key1 user@example.com

Method 1 — Specify the key on the command line with the -issh option.

The command line to use is:

ssh -i ~/.ssh/key1 user@example.com

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 example.com