While it’s best to keep just one public-private key pair per device, there are occasions when you’ll need to use several keys or have unusual key names. For example, you could use one SSH key pair for working on internal projects at your business, but a different key pair for accessing a client’s servers. You may also be using a different key pair for accessing your own private server.
When you need to use a second SSH key, managing them becomes a chore. Traditionally, you’d use ssh-add to add your keys to ssh-agent, typing in each key’s password. The problem is that you’d have to do this every time you restart your machine, which might get boring quickly. A better approach is to simplify the process of inserting keys, storing passwords, and specifying which key to use when connecting to specific servers.
