Cisco switch generates two pairs of keys

Question

The problem is: I generate a key pair on a switch and when i use: show crypto key mypubkey rsa it shows two keys. A geral-purpose key and an encryption key. The general-purpose key is the key i created because it has the same of my switch plus my domain. The other has the same name but with .server termination. I read on cisco website:

Secure Shell (SSH) may generate an additional RSA key pair if you generate a key pair on a router having no RSA keys. The additional key pair is used only by SSH and will have a name such as {router_FQDN}.server. For example, if a router name is "router1.cisco.com," the key name is "router1.cisco.com.server."

So. What is this key for?

Answer 1

General-purpose key pairs may be used for multiple purposes, including SSL (e.g., for the HTTPS management interface) and IPsec. The SSH key pair is reserved for SSH and no other tasks.

One practical difference in management between IPsec/SSL and SSH keys is that the former are typically signed (either by a public CA or by a company's in-house certificate chain) and are often only used until the certificate expires, at which point they're replaced. SSH keys usually aren't signed, and their management is often handled on a different maintenance schedule.