In this post I am going to show you how to configure crypto keypair without configuring host name or domain name on Cisco devices. A few network admins still have some confusion about if configuring the domain name on Cisco devices is a requirement to generate a crypto keypair or not. I believe this confusion comes from the error we get when we try to create a crypto keypair on Cisco devices before we’ve configured the domain name. The error would explicitly ask us to define the domain name first to generate the crypto keypair.